update ast

1 files changed, 0 insertions, 3204 deletions

diff --git a/ast/permmap.c b/ast/permmap.c
deleted file mode 100644
index 69b0962..0000000
--- a/ast/permmap.c
+++ /dev/null
@@ -1,3204 +0,0 @@
-/*
-*class++
-*  Name:
-*     PermMap
-
-*  Purpose:
-*     Coordinate permutation Mapping.
-
-*  Constructor Function:
-c     astPermMap
-f     AST_PERMMAP
-
-*  Description:
-*     A PermMap is a Mapping which permutes the order of coordinates,
-*     and possibly also changes the number of coordinates, between its
-*     input and output.
-*
-*     In addition to permuting the coordinate order, a PermMap may
-*     also assign constant values to coordinates. This is useful when
-*     the number of coordinates is being increased as it allows fixed
-*     values to be assigned to any new ones.
-
-*  Inheritance:
-*     The PermMap class inherits from the Mapping class.
-
-*  Attributes:
-*     The PermMap class does not define any new attributes beyond
-*     those which are applicable to all Mappings.
-
-*  Functions:
-c     The PermMap class does not define any new functions beyond those
-f     The PermMap class does not define any new routines beyond those
-*     which are applicable to all Mappings.
-
-*  Copyright:
-*     Copyright (C) 1997-2006 Council for the Central Laboratory of the
-*     Research Councils
-
-*  Licence:
-*     This program is free software: you can redistribute it and/or
-*     modify it under the terms of the GNU Lesser General Public
-*     License as published by the Free Software Foundation, either
-*     version 3 of the License, or (at your option) any later
-*     version.
-*
-*     This program is distributed in the hope that it will be useful,
-*     but WITHOUT ANY WARRANTY; without even the implied warranty of
-*     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-*     GNU Lesser General Public License for more details.
-*
-*     You should have received a copy of the GNU Lesser General
-*     License along with this program.  If not, see
-*     <http://www.gnu.org/licenses/>.
-
-*  Authors:
-*     RFWS: R.F. Warren-Smith (Starlink)
-
-*  History:
-*     29-FEB-1996 (RFWS):
-*        Original version.
-*     26-SEP-1996 (RFWS):
-*        Added external interface and I/O facilities.
-*     3-JUN-1997 (RFWS):
-*        Over-ride the MapMerge method.
-*     8-JAN-2003 (DSB):
-*        Changed private InitVtab method to protected astInitPermMapVtab
-*        method.
-*     11-SEP-2003 (DSB):
-*        Added methods astGetInPerm and astGetOutPerm.
-*     2-NOV-2004 (DSB):
-*        Added method astGetConstants.
-*     14-MAR-2006 (DSB):
-*        Override astEqual.
-*     2-MAY-2007 (DSB):
-*        Change MapSplit so that it does not try to use the
-*        implementation from the parent Mapping class, since this
-*        class can do a better job.
-*     11-SEP-2007 (DSB):
-*        In MapSplit, check that the permuted axis index is less than the
-*        number of axes available. Use AST__BAD otherwise.
-*     10-JAN-2011 (DSB):
-*        Add protected PermSplit attribute.
-*     11-FEB-2011 (DSB):
-*        Do not allow MapSplit to return a Mapping with zero outputs.
-*     22-NOV-2012 (DSB):
-*        When using a default inperm array (as indicated by a NULL pointer
-*        for inperm), ensure the array is padded with "-1" values if the
-*        number of inputs exceeds the number of outputs. Also do the
-*        equivalent for default outperm arrays.
-*     26-MAY-2016 (DSB):
-*        Allow the PermSplit attribute to be changed at any time. This is 
-*        because it does not directly affect either the forward or inverse
-*        transformation of the PermMap. The FitsCHan class needs to be able
-*        to change it to determine when checking if the -TAB algorithm can
-*        be used.
-*class--
-*/
-
-/* Module Macros. */
-/* ============== */
-/* Set the name of the class we are implementing. This indicates to
-   the header files that define class interfaces that they should make
-   "protected" symbols available. */
-#define astCLASS PermMap
-
-/* Include files. */
-/* ============== */
-/* Interface definitions. */
-/* ---------------------- */
-
-#include "globals.h"             /* Thread-safe global data access */
-#include "error.h"               /* Error reporting facilities */
-#include "memory.h"              /* Memory allocation facilities */
-#include "object.h"              /* Base Object class */
-#include "pointset.h"            /* Sets of points/coordinates */
-#include "mapping.h"             /* Coordinate mappings (parent class) */
-#include "unitmap.h"             /* Unit Mappings */
-#include "permmap.h"             /* Interface definition for this class */
-
-/* Error code definitions. */
-/* ----------------------- */
-#include "ast_err.h"             /* AST error codes */
-
-/* C header files. */
-/* --------------- */
-#include <stddef.h>
-#include <stdio.h>
-#include <string.h>
-#include <limits.h>
-
-/* Module Macros */
-/* ============= */
-/* A macro that returns the inperm or outperm value to use for a given
-   index, taking account of the possibility that the inperm or outperm may
-   be NULL (implying a unit permutation), and that he numbers of inputs
-   and outputs may not be equal. "perms" is a pointer to the integer
-   permutation array (inperm or outperm), "i" is the index of the required
-   element of the permutation array, and "maxperm" is one more than the
-   maximum value allowed in the permutation array (i.e. the number of
-   PermMap outputs if "perms" is inperm, or PermMap inputs if "perms" is
-   outperm). */
-#define PERMVAL( perms, i, maxperm ) ( perms ? perms[ i ] : (  i < maxperm ? i : -1 ))
-
-/* Module Variables. */
-/* ================= */
-
-/* Address of this static variable is used as a unique identifier for
-   member of this class. */
-static int class_check;
-
-/* Pointers to parent class methods which are extended by this class. */
-static AstPointSet *(* parent_transform)( AstMapping *, AstPointSet *, int, AstPointSet *, int * );
-
-
-#ifdef THREAD_SAFE
-/* Define how to initialise thread-specific globals. */
-#define GLOBAL_inits \
-   globals->Class_Init = 0;
-
-/* Create the function that initialises global data for this module. */
-astMAKE_INITGLOBALS(PermMap)
-
-/* Define macros for accessing each item of thread specific global data. */
-#define class_init astGLOBAL(PermMap,Class_Init)
-#define class_vtab astGLOBAL(PermMap,Class_Vtab)
-
-
-#include <pthread.h>
-
-
-#else
-
-
-/* Define the class virtual function table and its initialisation flag
-   as static variables. */
-static AstPermMapVtab class_vtab;   /* Virtual function table */
-static int class_init = 0;       /* Virtual function table initialised? */
-
-#endif
-
-/* External Interface Function Prototypes. */
-/* ======================================= */
-/* The following functions have public prototypes only (i.e. no
-   protected prototypes), so we must provide local prototypes for use
-   within this module. */
-AstPermMap *astPermMapId_( int, const int [], int, const int [], const double [], const char *, ... );
-
-/* Prototypes for Private Member Functions. */
-/* ======================================== */
-static AstPointSet *Transform( AstMapping *, AstPointSet *, int, AstPointSet *, int * );
-static double *GetConstants( AstPermMap *, int * );
-static double Rate( AstMapping *, double *, int, int, int * );
-static int Equal( AstObject *, AstObject *, int * );
-static int *GetInPerm( AstPermMap *, int * );
-static int *GetOutPerm( AstPermMap *, int * );
-static int *MapSplit( AstMapping *, int, const int *, AstMapping **, int * );
-static int MapMerge( AstMapping *, int, int, int *, AstMapping ***, int **, int * );
-static int NullPerm( AstPermMap *, int, int * );
-static void Copy( const AstObject *, AstObject *, int * );
-static void Delete( AstObject *, int * );
-static void Dump( AstObject *, AstChannel *, int * );
-
-static void SetPermSplit( AstPermMap *, int, int * );
-static void ClearPermSplit( AstPermMap *, int * );
-static int TestPermSplit( AstPermMap *, int * );
-static int GetPermSplit( AstPermMap *, int * );
-
-
-/* Member functions. */
-/* ================= */
-
-static int Equal( AstObject *this_object, AstObject *that_object, int *status ) {
-/*
-*  Name:
-*     Equal
-
-*  Purpose:
-*     Test if two PermMaps are equivalent.
-
-*  Type:
-*     Private function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     int Equal( AstObject *this, AstObject *that, int *status )
-
-*  Class Membership:
-*     PermMap member function (over-rides the astEqual protected
-*     method inherited from the astMapping class).
-
-*  Description:
-*     This function returns a boolean result (0 or 1) to indicate whether
-*     two PermMaps are equivalent.
-
-*  Parameters:
-*     this
-*        Pointer to the first Object (a PermMap).
-*     that
-*        Pointer to the second Object.
-*     status
-*        Pointer to the inherited status variable.
-
-*  Returned Value:
-*     One if the PermMaps are equivalent, zero otherwise.
-
-*  Notes:
-*     - A value of zero will be returned if this function is invoked
-*     with the global status set, or if it should fail for any reason.
-*/
-
-/* Local Variables: */
-   AstPermMap *that;
-   AstPermMap *this;
-   int *that_inp;
-   int *that_outp;
-   int *this_inp;
-   int *this_outp;
-   int i;
-   int nin;
-   int nin_that;
-   int nout;
-   int nout_that;
-   int p1;
-   int p2;
-   int result;
-   int that_inp_len;
-   int that_outp_len;
-   int this_inp_len;
-   int this_outp_len;
-
-/* Initialise. */
-   result = 0;
-
-/* Check the global error status. */
-   if ( !astOK ) return result;
-
-/* Obtain pointers to the two PermMap structures. */
-   this = (AstPermMap *) this_object;
-   that = (AstPermMap *) that_object;
-
-/* Check the second object is a PermMap. We know the first is a
-   PermMap since we have arrived at this implementation of the virtual
-   function. */
-   if( astIsAPermMap( that ) ) {
-
-/* Get the number of inputs and outputs and check they are the same for both. */
-      nin = astGetNin( this );
-      nout = astGetNout( this );
-      if( astGetNout( that ) == nout && astGetNin( that ) == nin ) {
-
-/* Assume the PermMaps are equivalent. */
-         result = 1;
-
-/* Get the number of inputs and outputs in the second PermMap. */
-         nin_that = astGetNin( that );
-         nout_that = astGetNout( that );
-
-/* Get pointers to the effective inperm and outperm array for each PermMap.
-   If the Invert flags of the two PermMaps are not equal, we swap the
-   arrays for the second PermMap in order to take account of the relative
-   inversion of the second PermMap. */
-         this_inp = this->inperm;
-         this_outp = this->outperm;
-
-         if(  astGetInvert( this ) ) {
-            this_inp_len =  nout;
-            this_outp_len =  nin;
-         } else {
-            this_inp_len =  nin;
-            this_outp_len =  nout;
-         }
-
-         if( astGetInvert( this ) != astGetInvert( that ) ) {
-            that_inp = that->outperm;
-            that_outp = that->inperm;
-
-            if(  astGetInvert( that ) ) {
-               that_inp_len =  nin_that;
-               that_outp_len =  nout_that;
-            } else {
-               that_inp_len =  nout_that;
-               that_outp_len =  nin_that;
-            }
-
-         } else {
-            that_inp = that->inperm;
-            that_outp = that->outperm;
-
-            if(  astGetInvert( that ) ) {
-               that_inp_len =  nout_that;
-               that_outp_len =  nin_that;
-            } else {
-               that_inp_len =  nin_that;
-               that_outp_len =  nout_that;
-            }
-         }
-
-/* Loop round every PermMap input. */
-         for( i = 0; i < nin; i++ ) {
-
-/* See what is fed to this input by the inverse transformation. A zero or
-   positive integer "p" value indicates that the input is fed from the
-   output with the corresponding index. A negative integer "p" value means
-   the input is fed a constant value stored at index (-p-1) in the
-   associated constants array. */
-            p1 = PERMVAL( this_inp, i, this_outp_len );
-            p2 = PERMVAL( that_inp, i, that_outp_len );
-
-/* If the "p" values differ, we may have evidence that the PermMaps are
-   not equivalent. */
-            if( p1 != p2 ) {
-
-/* If either "p" value is zero or positive, then the PermMaps are
-   definitely different since input "i" is fed from differing outputs, or
-   one is fed from an input and the other is fed a constant. */
-               if( p1 >= 0 || p2 >= 0 ) {
-                  result = 0;
-                  break;
-
-/* If both "p" values are negative, then both inputs are fed a constant
-   value. The PermMaps differ if these constants differ. */
-               } else if( this->constant[ -p1 - 1 ] !=
-                          that->constant[ -p2 - 1 ] ) {
-                  result = 0;
-                  break;
-               }
-            }
-         }
-
-/* If we have not yet discovered any evidence that the PermMaps differ,
-   go on to check each output in the same way that we have just checked the
-   inputs. */
-         if( result ) {
-            for( i = 0; i < nout; i++ ) {
-               p1 = PERMVAL( this_outp, i, this_inp_len );
-               p2 = PERMVAL( that_outp, i, that_inp_len );
-
-               if( p1 != p2 ) {
-                  if( p1 >= 0 || p2 >= 0 ) {
-                     result = 0;
-                     break;
-                  } else if( this->constant[ -p1 - 1 ] !=
-                             that->constant[ -p2 - 1 ] ) {
-                     result = 0;
-                     break;
-                  }
-               }
-            }
-         }
-      }
-   }
-
-/* If an error occurred, clear the result value. */
-   if ( !astOK ) result = 0;
-
-/* Return the result, */
-   return result;
-}
-
-static double *GetConstants( AstPermMap *this, int *status ){
-/*
-*+
-*  Name:
-*     astGetConstants
-
-*  Purpose:
-*     Return a pointer to the constants array of a PermMap.
-
-*  Type:
-*     Protected virtual function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     double *astGetConstants( AstPermMap *this )
-
-*  Class Membership:
-*     PermMap method
-
-*  Description:
-*     This function returns a pointer to a dynamically allocated array
-*     holding a copy of the constants array supplied when the PermMap was
-*     created.
-*
-*     Negative values in the arrays returned by the astGetInPerm and
-*     astGetOutPerm methods can be used as indices into the constants
-*     array returned by this method, if they are first negated and then
-*     decrement by one. Thus an inperm value of -3 refers to element 2 of
-*     the constants array.
-
-*  Parameters:
-*     this
-*        Pointer to the PermMap.
-
-*  Returned Value:
-*     A pointer to a dynamically allocated array holding a copy of the
-*     constants array. The pointer should be freed using astFree when it is
-*     no longer needed. NULL will be returned if the PermMap has no
-*     constants.
-
-*  Notes:
-*     - A value of NULL will be returned if this function is invoked
-*     with the global error status set, or if it should fail for any
-*     reason.
-*-
-*/
-
-/* Local Variables: */
-   double *result;                /* Pointer to the returned array */
-
-/* Initialise the returned result. */
-   result = NULL;
-
-/* Check the global error status. */
-   if ( !astOK ) return result;
-
-/* Allocate memory and put a copy of the InPerm array in it. */
-   result = (double *) astStore( NULL, this->constant, astSizeOf( this->constant ) );
-
-/* Return the result. */
-   return result;
-}
-
-static int *GetInPerm( AstPermMap *this, int *status ){
-/*
-*  Name:
-*     GetInPerm
-
-*  Purpose:
-*     Return a pointer to the InPerm array of a PermMap.
-
-*  Type:
-*     Protected virtual function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     int *astGetInPerm( AstPermMap *this, int *status )
-
-*  Class Membership:
-*     PermMap method
-
-*  Description:
-*     This function returns a pointer to a dynamically allocated array
-*     holding a copy of the InPerm array supplied when thre PermMap was
-*     created.
-
-*  Parameters:
-*     this
-*        Pointer to the PermMap.
-*     status
-*        Pointer to the inherited status variable.
-
-*  Returned Value:
-*     A pointer to a dynamically allocated array holding a copy of the
-*     InPerm array. The pointer should be freed using astFree when it is
-*     no longer needed. The number of elements in the array will be given
-*     by the value of the Nin attribute. The value in element "i" is the
-*     zero-based index of the output axis which provides values for input
-*     "i" when the inverse transformation is used. If the value in element
-*     "i" is less than zero, then input "i" is fed a constant value. This
-*     constant value is stored in the "constants" array (see astGetConstants)
-*     at an index equal to the absolute value of inperm[i], minus 1. Thus
-*     if element 3 of the array returned by this function has value -2,
-*     then input axis 3 is fed the value held in constants[1]. If the
-*     value of element "i" of the returned inperm array is greater than
-*     or equal to the number of output axes, then input "i" will be fed
-*     the constant AST__BAD.
-
-*  Notes:
-*     - A value of NULL will be returned if this function is invoked
-*     with the global error status set, or if it should fail for any
-*     reason.
-*/
-
-/* Local Variables: */
-   int i;                      /* Loop count */
-   int nin;                    /* Number of inputs. */
-   int *result;                /* Pointer to the returned array */
-
-/* Initialise the returned result. */
-   result = NULL;
-
-/* Check the global error status. */
-   if ( !astOK ) return result;
-
-/* If no inperm array is stored, every input is derived from the
-   corresponding output. Therefore, return an array holding 0 to Nin-1. */
-   if( !this->inperm ) {
-      nin = astGetNin( this );
-      result = (int *) astMalloc( sizeof( int ) * (size_t) nin );
-      if( astOK ) for( i = 0; i < nin; i++ ) result[ i ] = i;
-
-/* Otherwise, allocate memoy and put a copy of the InPerm array in it. */
-   } else {
-      result = (int *) astStore( NULL, this->inperm,
-                              sizeof( int ) * (size_t) astGetNin( this ) );
-   }
-
-/* Return the result. */
-   return result;
-}
-
-static int *GetOutPerm( AstPermMap *this, int *status ){
-/*
-*  Name:
-*     GetOutPerm
-
-*  Purpose:
-*     Return a pointer to the OutPerm array of a PermMap.
-
-*  Type:
-*     Protected virtual function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     int *astGetOutPerm( AstPermMap *this, int *status )
-
-*  Class Membership:
-*     PermMap method
-
-*  Description:
-*     This function returns a pointer to a dynamically allocated array
-*     holding a copy of the OutPerm array supplied when thre PermMap was
-*     created.
-
-*  Parameters:
-*     this
-*        Pointer to the PermMap.
-*     status
-*        Pointer to the inherited status variable.
-
-*  Returned Value:
-*     A pointer to a dynamically allocated array holding a copy of the
-*     OutPerm array. The pointer should be freed using astFree when it is
-*     no longer needed. The number of elements in the array will be given
-*     by the value of the Nout attribute. The value in element "i" is the
-*     zero-based index of the input axis which provides values for output
-*     "i" when the forward transformation is used. If the value in element
-*     "i" is less than zero, then output "i" is fed a constant value. This
-*     constant value is stored in the "constants" array (see astGetConstants)
-*     at an index equal to the absolute value of outperm[i], minus 1. Thus
-*     if element 3 of the array returned by this function has value -2,
-*     then output axis 3 is fed the value held in constants[1]. If the
-*     value of element "i" of the returned outperm array is greater than
-*     or equal to the number of input axes, then output "i" will be fed
-*     the constant AST__BAD.
-
-*  Notes:
-*     - A value of NULL will be returned if this function is invoked
-*     with the global error status set, or if it should fail for any
-*     reason.
-*/
-
-/* Local Variables: */
-   int i;                      /* Loop count */
-   int nout;                   /* Number of outputs. */
-   int *result;                /* Pointer to the returned array */
-
-/* Initialise the returned result. */
-   result = NULL;
-
-/* Check the global error status. */
-   if ( !astOK ) return result;
-
-/* If no outperm array is stored, every output is derived from the
-   corresponding input. Therefore, return an array holding 0 to Nout-1. */
-   if( !this->outperm ) {
-      nout = astGetNout( this );
-      result = (int *) astMalloc( sizeof( int ) * (size_t) nout );
-      if( astOK ) for( i = 0; i < nout; i++ ) result[ i ] = i;
-
-/* Otherwise, allocate memory and put a copy of the OutPerm array in it. */
-   } else {
-      result = (int *) astStore( NULL, this->outperm,
-                              sizeof( int ) * (size_t) astGetNout( this ) );
-   }
-
-/* Return the result. */
-   return result;
-}
-
-void astInitPermMapVtab_(  AstPermMapVtab *vtab, const char *name, int *status ) {
-/*
-*+
-*  Name:
-*     astInitPermMapVtab
-
-*  Purpose:
-*     Initialise a virtual function table for a PermMap.
-
-*  Type:
-*     Protected function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     void astInitPermMapVtab( AstPermMapVtab *vtab, const char *name )
-
-*  Class Membership:
-*     PermMap vtab initialiser.
-
-*  Description:
-*     This function initialises the component of a virtual function
-*     table which is used by the PermMap class.
-
-*  Parameters:
-*     vtab
-*        Pointer to the virtual function table. The components used by
-*        all ancestral classes will be initialised if they have not already
-*        been initialised.
-*     name
-*        Pointer to a constant null-terminated character string which contains
-*        the name of the class to which the virtual function table belongs (it
-*        is this pointer value that will subsequently be returned by the Object
-*        astClass function).
-*-
-*/
-
-/* Local Variables: */
-   astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
-   AstObjectVtab *object;        /* Pointer to Object component of Vtab */
-   AstMappingVtab *mapping;      /* Pointer to Mapping component of Vtab */
-
-/* Check the local error status. */
-   if ( !astOK ) return;
-
-
-/* Get a pointer to the thread specific global data structure. */
-   astGET_GLOBALS(NULL);
-
-/* Initialize the component of the virtual function table used by the
-   parent class. */
-   astInitMappingVtab( (AstMappingVtab *) vtab, name );
-
-/* Store a unique "magic" value in the virtual function table. This
-   will be used (by astIsAPermMap) to determine if an object belongs
-   to this class.  We can conveniently use the address of the (static)
-   class_check variable to generate this unique value. */
-   vtab->id.check = &class_check;
-   vtab->id.parent = &(((AstMappingVtab *) vtab)->id);
-
-/* Initialise member function pointers. */
-/* ------------------------------------ */
-/* Store pointers to the member functions (implemented here) that
-   provide virtual methods for this class. */
-   vtab->GetConstants = GetConstants;
-   vtab->GetInPerm = GetInPerm;
-   vtab->GetOutPerm = GetOutPerm;
-   vtab->ClearPermSplit = ClearPermSplit;
-   vtab->GetPermSplit = GetPermSplit;
-   vtab->SetPermSplit = SetPermSplit;
-   vtab->TestPermSplit = TestPermSplit;
-
-/* Save the inherited pointers to methods that will be extended, and
-   replace them with pointers to the new member functions. */
-   object = (AstObjectVtab *) vtab;
-   mapping = (AstMappingVtab *) vtab;
-
-   parent_transform = mapping->Transform;
-   mapping->Transform = Transform;
-
-   mapping->MapSplit = MapSplit;
-
-/* Store replacement pointers for methods which will be over-ridden by
-   new member functions implemented here. */
-   object->Equal = Equal;
-   mapping->MapMerge = MapMerge;
-   mapping->Rate = Rate;
-
-/* Declare the copy constructor, destructor and class dump function. */
-   astSetCopy( vtab, Copy );
-   astSetDelete( vtab, Delete );
-   astSetDump( vtab, Dump, "PermMap", "Coordinate permutation" );
-
-/* If we have just initialised the vtab for the current class, indicate
-   that the vtab is now initialised, and store a pointer to the class
-   identifier in the base "object" level of the vtab. */
-   if( vtab == &class_vtab ) {
-      class_init = 1;
-      astSetVtabClassIdentifier( vtab, &(vtab->id) );
-   }
-}
-
-static int MapMerge( AstMapping *this, int where, int series, int *nmap,
-                     AstMapping ***map_list, int **invert_list, int *status ) {
-/*
-*  Name:
-*     MapMerge
-
-*  Purpose:
-*     Simplify a sequence of Mappings containing a PermMap.
-
-*  Type:
-*     Private function.
-
-*  Synopsis:
-*     #include "mapping.h"
-*     int MapMerge( AstMapping *this, int where, int series, int *nmap,
-*                   AstMapping ***map_list, int **invert_list, int *status )
-
-*  Class Membership:
-*     PermMap method (over-rides the protected astMapMerge method
-*     inherited from the Mapping class).
-
-*  Description:
-*     This function attempts to simplify a sequence of Mappings by
-*     merging a nominated PermMap in the sequence with its neighbours,
-*     so as to shorten the sequence if possible.
-*
-*     In many cases, simplification will not be possible and the
-*     function will return -1 to indicate this, without further
-*     action.
-*
-*     In most cases of interest, however, this function will either
-*     attempt to replace the nominated PermMap with one which it
-*     considers simpler, or to merge it with the Mappings which
-*     immediately precede it or follow it in the sequence (both will
-*     normally be considered). This is sufficient to ensure the
-*     eventual simplification of most Mapping sequences by repeated
-*     application of this function.
-*
-*     In some cases, the function may attempt more elaborate
-*     simplification, involving any number of other Mappings in the
-*     sequence. It is not restricted in the type or scope of
-*     simplification it may perform, but will normally only attempt
-*     elaborate simplification in cases where a more straightforward
-*     approach is not adequate.
-
-*  Parameters:
-*     this
-*        Pointer to the nominated PermMap which is to be merged with
-*        its neighbours. This should be a cloned copy of the PermMap
-*        pointer contained in the array element "(*map_list)[where]"
-*        (see below). This pointer will not be annulled, and the
-*        PermMap it identifies will not be modified by this function.
-*     where
-*        Index in the "*map_list" array (below) at which the pointer
-*        to the nominated PermMap resides.
-*     series
-*        A non-zero value indicates that the sequence of Mappings to
-*        be simplified will be applied in series (i.e. one after the
-*        other), whereas a zero value indicates that they will be
-*        applied in parallel (i.e. on successive sub-sets of the
-*        input/output coordinates).
-*     nmap
-*        Address of an int which counts the number of Mappings in the
-*        sequence. On entry this should be set to the initial number
-*        of Mappings. On exit it will be updated to record the number
-*        of Mappings remaining after simplification.
-*     map_list
-*        Address of a pointer to a dynamically allocated array of
-*        Mapping pointers (produced, for example, by the astMapList
-*        method) which identifies the sequence of Mappings. On entry,
-*        the initial sequence of Mappings to be simplified should be
-*        supplied.
-*
-*        On exit, the contents of this array will be modified to
-*        reflect any simplification carried out. Any form of
-*        simplification may be performed. This may involve any of: (a)
-*        removing Mappings by annulling any of the pointers supplied,
-*        (b) replacing them with pointers to new Mappings, (c)
-*        inserting additional Mappings and (d) changing their order.
-*
-*        The intention is to reduce the number of Mappings in the
-*        sequence, if possible, and any reduction will be reflected in
-*        the value of "*nmap" returned. However, simplifications which
-*        do not reduce the length of the sequence (but improve its
-*        execution time, for example) may also be performed, and the
-*        sequence might conceivably increase in length (but normally
-*        only in order to split up a Mapping into pieces that can be
-*        more easily merged with their neighbours on subsequent
-*        invocations of this function).
-*
-*        If Mappings are removed from the sequence, any gaps that
-*        remain will be closed up, by moving subsequent Mapping
-*        pointers along in the array, so that vacated elements occur
-*        at the end. If the sequence increases in length, the array
-*        will be extended (and its pointer updated) if necessary to
-*        accommodate any new elements.
-*
-*        Note that any (or all) of the Mapping pointers supplied in
-*        this array may be annulled by this function, but the Mappings
-*        to which they refer are not modified in any way (although
-*        they may, of course, be deleted if the annulled pointer is
-*        the final one).
-*     invert_list
-*        Address of a pointer to a dynamically allocated array which,
-*        on entry, should contain values to be assigned to the Invert
-*        attributes of the Mappings identified in the "*map_list"
-*        array before they are applied (this array might have been
-*        produced, for example, by the astMapList method). These
-*        values will be used by this function instead of the actual
-*        Invert attributes of the Mappings supplied, which are
-*        ignored.
-*
-*        On exit, the contents of this array will be updated to
-*        correspond with the possibly modified contents of the
-*        "*map_list" array.  If the Mapping sequence increases in
-*        length, the "*invert_list" array will be extended (and its
-*        pointer updated) if necessary to accommodate any new
-*        elements.
-*     status
-*        Pointer to the inherited status variable.
-
-*  Returned Value:
-*     If simplification was possible, the function returns the index
-*     in the "map_list" array of the first element which was
-*     modified. Otherwise, it returns -1 (and makes no changes to the
-*     arrays supplied).
-
-*  Notes:
-*     - A value of -1 will be returned if this function is invoked
-*     with the global error status set, or if it should fail for any
-*     reason.
-*/
-
-/* Local Variables: */
-   AstMapping *map;              /* Pointer to Mapping */
-   AstMapping *new;              /* Pointer to replacement Mapping */
-   AstPermMap *permmap;          /* Pointer to PermMap */
-   const char *class;            /* Pointer to Mapping class string */
-   double *con;                  /* Pointer to constants array */
-   double constant;              /* Constant value */
-   int *inperm;                  /* Pointer to "inperm" permutation array */
-   int *newperm;                 /* Pointer to new permutation array */
-   int *outperm;                 /* Pointer to "outperm" permutation array */
-   int *perm;                    /* Pointer to individual permutation array */
-   int back;                     /* Considering inverse transformation? */
-   int coord;                    /* Loop counter for coordinates */
-   int icon;                     /* Loop counter for constants */
-   int iend;                     /* Loop ending value */
-   int imap1;                    /* Index of first Mapping */
-   int imap2;                    /* Index of last Mapping */
-   int imap;                     /* Loop counter for Mappings */
-   int inc;                      /* Loop increment */
-   int invert;                   /* Invert attribute value */
-   int istart;                   /* Loop starting value */
-   int maxperm;                  /* Max value (+1) allowed in permutation array */
-   int ncon;                     /* Number of constants */
-   int ncoord_in;                /* Effective number of input coordinates */
-   int ncoord_out;               /* Effective number of output coordinates */
-   int ngone;                    /* Number of Mappings eliminated */
-   int nin;                      /* Total number of input coordinates */
-   int ninsum;                   /* Accumulated count of input coordinates */
-   int nout;                     /* Total number of output coordinates */
-   int noutsum;                  /* Accumulated count of output coordinates */
-   int nperm;                    /* Number of permutation array elements */
-   int p;                        /* Permuted coordinate index */
-   int result;                   /* Result value to return */
-   int simpler;                  /* Mapping(s) simplified? */
-   int store_in;                 /* Need to store "inperm" array contents? */
-   int store_out;                /* Need to store "outperm" array contents? */
-   int unit;                     /* Replacement Mapping is a UnitMap? */
-
-/* Initialise the returned result. */
-   result = -1;
-
-/* Check the global error status. */
-   if ( !astOK ) return result;
-
-/* Further initialisation. */
-   con = NULL;
-   inperm = outperm = NULL;
-   ncon = 0;
-   permmap = NULL;
-
-/* In series. */
-/* ---------- */
-/* Handle the case where the Mappings are connected in series. */
-   if ( series ) {
-
-/* Search adjacent lower-numbered Mappings until one is found which is
-   not a PermMap or a UnitMap. */
-      imap1 = where;
-      while ( ( imap1 - 1 ) >= 0 ) {
-         class = astGetClass( ( *map_list )[ imap1 - 1 ] );
-         if ( astOK ) {
-            if ( strcmp( class, "PermMap" ) &&
-                 strcmp( class, "UnitMap" ) ) break;
-            imap1--;
-         }
-      }
-
-/* Similarly search adjacent higher-numbered Mappings. */
-      imap2 = where;
-      while ( ( imap2 + 1 ) < *nmap ) {
-         class = astGetClass( ( *map_list )[ imap2 + 1 ] );
-         if ( astOK ) {
-            if ( strcmp( class, "PermMap" ) &&
-                 strcmp( class, "UnitMap" ) ) break;
-            imap2++;
-         }
-      }
-
-/* Obtain a pointer to the first Mapping found and determine if it is
-   to be applied with its Invert attribute set. */
-      map = ( *map_list )[ imap1 ];
-      invert = ( *invert_list )[ imap1 ];
-
-/* Use this first Mapping (allowing for how its Invert attribute is
-   currently set) to determine the number of input coordinates that
-   the simplified Mapping should have. */
-      if ( astGetInvert( map ) ) {
-         nin = invert ? astGetNin( map ) : astGetNout( map );
-      } else {
-         nin = invert ? astGetNout( map ) : astGetNin( map );
-      }
-
-/* Repeat this process for the last Mapping found, to determine the
-   number of output coordinates for the simplified Mapping. */
-      map = ( *map_list )[ imap2 ];
-      invert = ( *invert_list )[ imap2 ];
-      if ( astGetInvert( map ) ) {
-         nout = invert ? astGetNout( map ) : astGetNin( map );
-      } else {
-         nout = invert ? astGetNin( map ) : astGetNout( map );
-      }
-
-/* Allocate memory to hold input and output permutation arrays for the
-   simplified Mapping, together with a list of constants. */
-      inperm = astMalloc( sizeof( int ) * (size_t) nin );
-      outperm = astMalloc( sizeof( int ) * (size_t) nout );
-      con = astMalloc( sizeof( double ) * (size_t) ( nin + nout ) );
-      if ( astOK ) {
-
-/* Initialise the number of constants. */
-         ncon = 0;
-
-/* Loop twice, to calculate the forward and inverse (backward)
-   simplified permutation arrays in turn. */
-         for ( back = 0; back <= 1; back++ ) {
-
-/* Obtain a pointer to the appropriate (forward/inverse) permutation
-   array that we wish to fill, and obtain the number of elements it
-   will contain. Initialise the array contents to represent a null
-   permutation.*/
-            newperm = back ? outperm : inperm;
-            nperm = back ? nout : nin;
-            for ( coord = 0; coord < nperm; coord++ ) newperm[ coord ] = coord;
-
-/* Set up limits to scan through the list of Mappings being merged in
-   either the forward or reverse order, as required. */
-            istart = back ? imap2 : imap1;
-            iend = back ? imap1 - 1 : imap2 + 1;
-            inc = back ? -1 : 1;
-
-/* Loop through the Mappings, obtaining a pointer to each, together
-   with the value to be used for its Invert attribute. Invert this
-   attribute value if calculating the overall inverse (backward)
-   permutation array. */
-            for ( imap = istart; imap != iend; imap += inc ) {
-               map = ( *map_list )[ imap ];
-               invert = ( *invert_list )[ imap ];
-               if ( back ) invert = !invert;
-
-/* Determine the class to which the Mapping belongs. */
-               class = astGetClass( map );
-               if ( astOK ) {
-
-/* If it is a PermMap, obtain a pointer to the PermMap structure and
-   hence to the relevant permutation array.  Otherwise (if it is a
-   UnitMap), leave the permutation array pointer NULL, which indicates
-   a null permutation. */
-                  perm = NULL;
-                  maxperm = astGetNout( map );
-                  if ( !strcmp( class, "PermMap" ) ) {
-                     permmap = (AstPermMap *) map;
-                     perm = invert ? permmap->outperm : permmap->inperm;
-                  }
-
-/* Obtain the effective number of output coordinates associated with
-   this individual Mapping (when transforming points in the direction
-   to which this permutation array applies). */
-                  if ( astGetInvert( map ) ) {
-                     ncoord_out = invert ? astGetNout( map ) :
-                                           astGetNin( map );
-                  } else {
-                     ncoord_out = invert ? astGetNin( map ) :
-                                           astGetNout( map );
-                  }
-
-/* Loop through the elements of the simplified permutation array to
-   accumulate the effects of the current individual Mapping. */
-                  if ( astOK ) {
-                     for ( coord = 0; coord < nperm; coord++ ) {
-
-/* Find the effective input coordinate for the current Mapping from
-   the permutation accumulated so far, and check this is not
-   negative. If it is, the accumulated permutation refers to a "bad"
-   coordinate value or a constant, so the current Mapping makes no
-   further difference. */
-                        p = newperm[ coord ];
-                        if ( p >= 0 ) {
-
-/* Otherwise, obtain the permuting effect of the current Mapping,
-   allowing for the possibility of its permutation array being NULL
-   (implying a null permutation). */
-                           p = PERMVAL( perm, p, maxperm );
-
-/* If the permuted index refers to a valid (effective) output
-   coordinate for the individual Mapping, then accumulate its effect
-   in the overall permutation array. */
-                           if ( ( p >= 0 ) && ( p < ncoord_out ) ) {
-                              newperm[ coord ] = p;
-
-/* Otherwise (this can only occur if the individual Mapping is a
-   PermMap), determine whether it refers to a "bad" coordinate value
-   or a constant. If the former, extract the constant's value,
-   otherwise use a constant value of AST__BAD. */
-                           } else {
-                              if ( ( p < 0 ) && permmap->constant ) {
-                                 constant = permmap->constant[ (-p) - 1 ];
-                              } else {
-                                 constant = AST__BAD;
-                              }
-
-/* If the result (however reached) is a coordinate value of AST__BAD,
-   then mark the accumulated permutation array with a value of -1 to
-   indicate this. */
-                              if ( constant == AST__BAD ) {
-                                 newperm[ coord ] = -1;
-
-/* Otherwise, search the array of constants to see if this one has
-   been encountered before. If not, append the new constant to the
-   list. */
-                              } else {
-                                 for ( icon = 0; icon < ncon; icon++ ) {
-                                    if ( con[ icon ] == constant ) break;
-                                 }
-                                 if ( icon == ncon ) con[ ncon++ ] = constant;
-
-/* Store a (negative) reference to the new constant in the accumulated
-   permutation array (note we use an extra offset of -1 here in
-   forming these references, so that the value -1 itself can be used
-   to indicate a "bad" coordinate value without an entry in the
-   constants array). */
-                                 newperm[ coord ] = (-icon) - 2;
-                              }
-                           }
-                        }
-                     }
-                  }
-               }
-            }
-         }
-      }
-
-/* In parallel. */
-/* ------------ */
-/* Handle the case where the Mappings are connected in parallel. */
-   } else {
-
-/* Obtain a pointer to the nominated Mapping (which is a PermMap) and
-   determine if it is to be applied with its Invert attribute set. */
-      map = ( *map_list )[ where ];
-      invert = ( *invert_list )[ where ];
-
-/* Use this nominated Mapping to initialise the counts of input and
-   output coordinates for the simplified Mapping (allowing for how its
-   Invert attribute is currently set). */
-      if ( astGetInvert( map ) ) {
-         nin = invert ? astGetNin( map ) : astGetNout( map );
-         nout = invert ? astGetNout( map ) : astGetNin( map );
-      } else {
-         nin = invert ? astGetNout( map ) : astGetNin( map );
-         nout = invert ? astGetNin( map ) : astGetNout( map );
-      }
-
-/* Search adjacent lower-numbered Mappings until one is found which is
-   not a PermMap or a UnitMap. */
-      imap1 = where;
-      while ( astOK && ( ( imap1 - 1 ) >= 0 ) ) {
-         map = ( *map_list )[ imap1 - 1 ];
-         class = astGetClass( map );
-         if ( astOK ) {
-            if ( strcmp( class, "PermMap" ) &&
-                 strcmp( class, "UnitMap" ) ) break;
-
-/* For each Mapping found, obtain the effective numbers of input and
-   output coordinates (allowing for all the direction flags, as above)
-   and accumulate the total count of input and output coordinates for
-   the overall simplified Mapping. */
-            invert = ( *invert_list )[ imap1 - 1 ];
-            if ( astGetInvert( map ) ) {
-               nin += ( invert ? astGetNin( map ) : astGetNout( map ) );
-               nout += ( invert ? astGetNout( map ) : astGetNin( map ) );
-            } else {
-               nin += ( invert ? astGetNout( map ) : astGetNin( map ) );
-               nout += ( invert ? astGetNin( map ) : astGetNout( map ) );
-            }
-            imap1--;
-         }
-      }
-
-/* Similarly search higher-numbered Mappings and accumulate their
-   coordinate counts. */
-      imap2 = where;
-      while ( astOK && ( ( imap2 + 1 ) < *nmap ) ) {
-         map = ( *map_list )[ imap2 + 1 ];
-         class = astGetClass( map );
-         if ( astOK ) {
-            if ( strcmp( class, "PermMap" ) &&
-                 strcmp( class, "UnitMap" ) ) break;
-            invert = ( *invert_list )[ imap2 + 1 ];
-            if ( astGetInvert( map ) ) {
-               nin += ( invert ? astGetNin( map ) : astGetNout( map ) );
-               nout += ( invert ? astGetNout( map ) : astGetNin( map ) );
-            } else {
-               nin += ( invert ? astGetNout( map ) : astGetNin( map ) );
-               nout += ( invert ? astGetNin( map ) : astGetNout( map ) );
-            }
-            imap2++;
-         }
-      }
-
-/* Allocate memory to hold input and output permutation arrays for the
-   simplified Mapping, together with a list of constants. */
-      inperm = astMalloc( sizeof( int ) * (size_t) nin );
-      outperm = astMalloc( sizeof( int ) * (size_t) nout );
-      con = astMalloc( sizeof( double ) * (size_t) ( nin + nout ) );
-      if ( astOK ) {
-
-/* Initialise the number of constants. */
-         ncon = 0;
-
-/* Loop twice, to calculate the forward and inverse (backward)
-   simplified permutation arrays in turn. */
-         for ( back = 0; back <= 1; back++ ) {
-
-/* Obtain a pointer to the appropriate (forward/inverse) permutation
-   array that we wish to fill, and obtain the number of elements it
-   will contain. */
-            newperm = back ? outperm : inperm;
-            nperm = back ? nout : nin;
-
-/* Initialise counts of (effective) input and output coordinates. */
-            ninsum = noutsum = 0;
-
-/* Loop through the Mappings, obtaining a pointer to each, together
-   with the value to be used for its Invert attribute.  Invert this
-   attribute value if calculating the overall inverse (backward)
-   permutation array. */
-            for ( imap = imap1; imap <= imap2; imap++ ) {
-               map = ( *map_list )[ imap ];
-               invert = ( *invert_list )[ imap ];
-               if ( back ) invert = !invert;
-
-/* Determine the class to which the Mapping belongs. */
-               class = astGetClass( map );
-               if ( astOK ) {
-
-/* If it is a PermMap, obtain a pointer to the PermMap structure and
-   hence to the relevant permutation array.  Otherwise (if it is a
-   UnitMap), leave the permutation array pointer NULL, which indicates
-   a null permutation. */
-                  perm = NULL;
-                  maxperm = astGetNout( map );
-                  if ( !strcmp( class, "PermMap" ) ) {
-                     permmap = (AstPermMap *) map;
-                     perm = invert ? permmap->outperm : permmap->inperm;
-                  }
-
-/* Obtain the effective number of input and output coordinates
-   associated with this individual Mapping (when transforming points
-   in the direction to which this permutation array applies). */
-                  if ( astGetInvert( map ) ) {
-                     ncoord_in = invert ? astGetNin( map ) :
-                                          astGetNout( map );
-                     ncoord_out = invert ? astGetNout( map ) :
-                                           astGetNin( map );
-                  } else {
-                     ncoord_in = invert ? astGetNout( map ) :
-                                          astGetNin( map );
-                     ncoord_out = invert ? astGetNin( map ) :
-                                           astGetNout( map );
-                  }
-
-/* Loop through the (effective) input coordinates of the current
-   individual Mapping to accumulate their effect on the overall
-   permutation array. */
-                  if ( astOK ) {
-                     for ( coord = 0; coord < ncoord_in; coord++ ) {
-
-/* Obtain the permuting effect of the current Mapping, allowing for
-   the possibility of its permutation array being NULL. */
-                        p = PERMVAL( perm, coord, maxperm );
-
-/* If the permuted index refers to a valid (effective) output
-   coordinate for the individual Mapping, then accumulate its effect
-   on the overall permutation array, allowing for the coordinate
-   numbering offset produced by any Mappings already accumulated. */
-                        if ( ( p >= 0 ) && ( p < ncoord_out ) ) {
-                           newperm[ coord + ninsum ] = p + noutsum;
-
-/* Otherwise (this can only occur if the individual Mapping is a
-   PermMap), determine whether it refers to a "bad" coordinate value
-   or a constant. If the former, extract the constant's value,
-   otherwise use a constant value of AST__BAD. */
-                        } else {
-                           if ( ( p < 0 ) && permmap->constant ) {
-                              constant = permmap->constant[ (-p) - 1 ];
-                           } else {
-                              constant = AST__BAD;
-                           }
-
-/* If the result (however reached) is a coordinate value of AST__BAD,
-   then mark the accumulated permutation array with a value of -1 to
-   indicate this. */
-                           if ( constant == AST__BAD ) {
-                              newperm[ coord + ninsum ] = -1;
-
-/* Otherwise, search the array of constants to see if this one has
-   been encountered before. If not, append the new constant to the
-   list. */
-                           } else {
-                              int icon;
-                              for ( icon = 0; icon < ncon; icon++ ) {
-                                 if ( con[ icon ] == constant ) break;
-                              }
-                              if ( icon == ncon ) con[ ncon++ ] = constant;
-
-/* Store a (negative) reference to the new constant in the accumulated
-   permutation array (note we use an extra offset of -1 here in
-   forming these references, so that the value -1 itself can be used
-   to indicate a "bad" coordinate value without an entry in the
-   constants array). */
-                              newperm[ coord + ninsum ] = (-icon) - 2;
-                           }
-                        }
-                     }
-                  }
-
-/* Accumulate the counts of (effective) input and output coordinates
-   for each individual Mapping. */
-                  ninsum += ncoord_in;
-                  noutsum += ncoord_out;
-               }
-            }
-         }
-      }
-   }
-
-/* Inspect each element of the accumulated "inperm" array to determine
-   if it needs to be stored by the replacement PermMap. */
-   if ( astOK ) {
-      store_in = 0;
-      for ( coord = 0; coord < nin; coord++ ) {
-
-/* It need not be stored if it produces a null permutation, where each
-   input coordinate takes its value from the corresponding output
-   coordinate (or where a "bad" value results if there is no
-   corresponding output coordinate). Note any deviation from this
-   pattern. */
-         if ( coord < nout ) {
-            store_in = store_in || ( inperm[ coord ] != coord );
-         } else {
-            store_in = store_in || ( inperm[ coord ] != -1 );
-         }
-
-/* Also convert permutation array values of -1 into non-existent
-   positive coordinate indices (indicating "bad" coordinate values)
-   and adjust (negative) references to constants by +1 to eliminate
-   the extra offset of -1 used temporarily above. This returns the
-   permutation array values to normal. */
-         if ( inperm[ coord ] < 0 ) {
-            if ( !++inperm[ coord ] ) inperm[ coord ] = nout;
-         }
-      }
-
-/* Similarly inspect the "outperm" array and return its values to
-   normal. */
-      store_out = 0;
-      for ( coord = 0; coord < nout; coord++ ) {
-         if ( coord < nin ) {
-            store_out = store_out || ( outperm[ coord ] != coord );
-         } else {
-            store_out = store_out || ( outperm[ coord ] != -1 );
-         }
-         if ( outperm[ coord ] < 0 ) {
-            if ( !++outperm[ coord ] ) outperm[ coord ] = nin;
-         }
-      }
-
-/* Determine how many adjacent Mappings can be eliminated by merging
-   them. */
-      ngone = imap2 - imap1;
-
-/* Determine if the resultant PermMap can be simplified still further
-   to become a UnitMap (a null Mapping). This will be the case if both
-   the forward and inverse coordinate permutations it produces are
-   null, and if the number of input and output coordinates are
-   equal. */
-      unit = !store_in && !store_out && ( nin == nout );
-
-/* We must now determine whether we have actually produced any
-   simplification. This is important, because if we indicate a
-   simplification when none has, in fact, been achieved, then this
-   function may get called over and over again without end. */
-
-/* Simplification is clearly evident if (a) Mappings have been
-   eliminated ("ngone" is non-zero), or (b) a PermMap has been reduced
-   to a UnitMap, or (c) where there was originally only one PermMap to
-   simplify, its invert flag was set (the replacement Mapping will
-   always have this flag cleared). */
-      simpler = ngone || unit || ( *invert_list )[ where ];
-
-/* If the above tests do not indicate simplification, then we can only
-   be considering the case where there was a single initial
-   PermMap. In this case we have also achieved simplification if
-   either the "inperm" or "outperm" array no longer needs storing
-   whereas previously it was stored. */
-      permmap = (AstPermMap *) ( *map_list )[ where ];
-      if ( !simpler ) {
-         simpler = ( !store_in && !NullPerm( permmap, 0, status ) ) ||
-                   ( !store_out && !NullPerm( permmap, 1, status ) );
-      }
-
-/* If we still haven't detected any simplification, then compare the
-   original and replacement "inperm" arrays (if present) in detail for
-   equality.  We declare simplification to have occurred if they
-   differ. */
-      if ( !simpler && store_in ) {
-         for ( coord = 0; coord < nin; coord++ ) {
-            simpler = ( inperm[ coord ] != permmap->inperm[ coord ] );
-            if ( simpler ) break;
-         }
-      }
-
-/* Similarly, if necessary, compare the original and replacement
-   "outperm" arrays. */
-      if ( !simpler && store_out ) {
-         for ( coord = 0; coord < nout; coord++ ) {
-            simpler = ( outperm[ coord ] != permmap->outperm[ coord ] );
-            if ( simpler ) break;
-         }
-      }
-
-/* Do nothing more unless there has been some simplification. */
-      if ( simpler ) {
-
-/* If the PermMaps (and UnitMaps) can be replaced by a UnitMap, then
-   create the replacement. */
-         if ( unit ) {
-            new = (AstMapping *) astUnitMap( nin, "", status );
-
-/* Otherwise, create a replacement PermMap, setting as many arguments
-   to NULL in the constructor function as can be achieved without
-   affecting the result. */
-         } else {
-            new = (AstMapping *) astPermMap( nin, store_in ? inperm : NULL,
-                                             nout, store_out ? outperm : NULL,
-                                             ncon ? con : NULL, "", status );
-         }
-
-/* Annul the pointers to all the Mappings that are being replaced. */
-         if ( astOK ) {
-            for ( imap = imap1; imap <= imap2; imap++ ) {
-               ( *map_list )[ imap ] = astAnnul( ( *map_list )[ imap ] );
-            }
-
-/* Insert the new pointer and the associated invert flag. */
-            ( *map_list )[ imap1 ] = new;
-            ( *invert_list )[ imap1 ] = 0;
-
-/* Loop to close the resulting gap by moving subsequent elements down
-   in the arrays. */
-            for ( imap = imap2 + 1; imap < *nmap; imap++ ) {
-               ( *map_list )[ imap - ngone ] = ( *map_list )[ imap ];
-               ( *invert_list )[ imap - ngone ] = ( *invert_list )[ imap ];
-            }
-
-/* Clear the vacated elements at the end. */
-            for ( imap = *nmap - ngone; imap < *nmap; imap++ ) {
-               ( *map_list )[ imap ] = NULL;
-               ( *invert_list )[ imap ] = 0;
-            }
-
-/* Decrement the Mapping count and return the index of the first
-   modified element. */
-            ( *nmap ) -= ngone;
-            result = imap1;
-         }
-      }
-   }
-
-/* Free the workspace arrays. */
-   inperm = astFree( inperm );
-   outperm = astFree( outperm );
-   con = astFree( con );
-
-/* If an error occurred, clear the returned value. */
-   if ( !astOK ) result = -1;
-
-/* Return the result. */
-   return result;
-}
-
-static int *MapSplit( AstMapping *this_map, int nin, const int *in, AstMapping **map, int *status ){
-/*
-*  Name:
-*     MapSplit
-
-*  Purpose:
-*     Create a Mapping representing a subset of the inputs of an existing
-*     PermMap.
-
-*  Type:
-*     Private function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     int *MapSplit( AstMapping *this, int nin, const int *in, AstMapping **map, int *status )
-
-*  Class Membership:
-*     PermMap method (over-rides the protected astMapSplit method
-*     inherited from the Mapping class).
-
-*  Description:
-*     This function creates a new Mapping by picking specified inputs from
-*     an existing PermMap. This is only possible if the specified inputs
-*     correspond to some subset of the PermMap outputs. That is, there
-*     must exist a subset of the PermMap outputs for which each output
-*     depends only on the selected PermMap inputs, and not on any of the
-*     inputs which have not been selected. If this condition is not met
-*     by the supplied PermMap, then a NULL Mapping is returned.
-
-*  Parameters:
-*     this
-*        Pointer to the PermMap to be split (the PermMap is not actually
-*        modified by this function).
-*     nin
-*        The number of inputs to pick from "this".
-*     in
-*        Pointer to an array of indices (zero based) for the inputs which
-*        are to be picked. This array should have "nin" elements. If "Nin"
-*        is the number of inputs of the supplied PermMap, then each element
-*        should have a value in the range zero to Nin-1.
-*     map
-*        Address of a location at which to return a pointer to the new
-*        Mapping. This Mapping will have "nin" inputs (the number of
-*        outputs may be different to "nin"). A NULL pointer will be
-*        returned if the supplied PermMap has no subset of outputs which
-*        depend only on the selected inputs.
-*     status
-*        Pointer to the inherited status variable.
-
-*  Returned Value:
-*     A pointer to a dynamically allocated array of ints. The number of
-*     elements in this array will equal the number of outputs for the
-*     returned Mapping. Each element will hold the index of the
-*     corresponding output in the supplied PermMap. The array should be
-*     freed using astFree when no longer needed. A NULL pointer will
-*     be returned if no output Mapping can be created.
-
-*  Notes:
-*     - If this function is invoked with the global error status set,
-*     or if it should fail for any reason, then NULL values will be
-*     returned as the function value and for the "map" pointer.
-*/
-
-/* Local Variables: */
-   AstPermMap *this;          /* Pointer to PermMap structure */
-   double *con;               /* Pointer to constants array */
-   int *inp;                  /* Input perm array to use with supplied PermMap */
-   int *inpm;                 /* Input perm array to use with new PermMap */
-   int *outp;                 /* Output perm array to use with supplied PermMap */
-   int *outpm;                /* Output perm array to use with new PermMap */
-   int *result;               /* Pointer to returned array */
-   int i;                     /* Loop count */
-   int iin;                   /* Mapping input index */
-   int iout;                  /* Output index */
-   int j;                     /* Loop count */
-   int nout;                  /* No. of outputs in the new PermMap */
-   int npin;                  /* No. of inputs in the supplied Mapping */
-   int npout;                 /* No. of outputs in the supplied Mapping */
-   int ok;                    /* Are input indices OK? */
-
-/* Initialise */
-   result = NULL;
-   *map = NULL;
-
-/* Check the global error status. */
-   if ( !astOK ) return result;
-
-
-/* Get a pointer to the PermMap structure. */
-   this = (AstPermMap *) this_map;
-
-/* Get the number of inputs and outputs in the supplied PermMap. */
-   npin = astGetNin( this );
-   npout = astGetNout( this );
-
-/* Check all input axis indices are valid. */
-   ok = 1;
-   for( i = 0; i < nin; i++ ) {
-      if( in[ i ] < 0 || in[ i ] >= npin ) {
-         ok = 0;
-         break;
-      }
-   }
-
-/* Get pointers to the input and output permutation arrays and constant
-   array taking account of whether the PermMap has been inverted. */
-   if( astGetInvert( this ) ) {
-      outp = this->inperm;
-      inp = this->outperm;
-   } else {
-      outp = this->outperm;
-      inp = this->inperm;
-   }
-   con = this->constant;
-
-/* The "normal" method, as described in the prologue. */
-   if( astGetPermSplit( this ) == 0 ) {
-
-/* Allocate memory for the returned array of output indices. */
-      result = astMalloc( sizeof( int )*(size_t) npout );
-
-/* Allocate memory for the inperm and outperm arrays of the returned
-   PermMap. Make these the largest they could possible need to be. */
-      inpm = astMalloc( sizeof( int )*(size_t) npin );
-      outpm = astMalloc( sizeof( int )*(size_t) npout );
-      if( astOK ) {
-
-/* Initialise number of outputs in returned PermMap. */
-         nout = 0;
-
-/* Loop round each output of the supplied PermMap. */
-         for( iout = 0; iout < npout; iout++ ) {
-
-/* Is this output fed by one of the selected inputs? If so store the input
-   index of the returned Mapping, which feeds this output and add this
-   output index to the list of returned outputs. */
-            iin = PERMVAL( outp, iout, npin );
-            if( iin >= 0 && iin < npin ) {
-               for( i = 0; i < nin; i++ ) {
-                  if( in[ i ] == iin ) {
-                     outpm[ nout ] = i;
-                     result[ nout ] = iout;
-                     nout++;
-                     break;
-                  }
-               }
-            }
-         }
-
-/* We now need to set up the inperm array for the returned PermMap. This
-   ensures that the inverse transformation in the returned Mapping provides
-   values for the selected inputs. Loop round all the selected inputs. */
-         for( i = 0; i < nin; i++ ) {
-            iin = in[ i ];
-
-/* Is this input constant or fed by one of the selected outputs? If so store
-   the output or constant index in the returned Mapping which feeds this
-   input. */
-            ok = 0;
-            iout = PERMVAL( inp, iin, npout );
-            if( iout >= 0 && iout < npout ) {
-               for( j = 0; j < nout; j++ ) {
-                  if( result[ j ] == iout ) {
-                     ok = 1;
-                     inpm[ i ] = j;
-                     break;
-                  }
-               }
-            } else {
-               inpm[ i ] = iout;
-               ok = 1;
-            }
-
-/* If this input is fed by an output which has not been selected, then we
-   cannot produce the required Mapping. */
-            if( !ok ) break;
-         }
-
-/* If possible produce the returned PermMap. Otherwise, free the returned
-   array. */
-         if( ok && nout > 0 ) {
-            *map = (AstMapping *) astPermMap( nin, inpm, nout, outpm, con, "", status );
-         } else {
-            result = astFree( result );
-         }
-
-/* Free other resources. */
-         inpm = astFree( inpm );
-         outpm = astFree( outpm );
-      }
-
-/* The "alternative" method. Only the inperm array is used - the outperm
-   array is assumed to be an exact inverse of the inperm array. In other
-   words, only the inverse transformation is used, and the forward
-   transformation is assumed to be the exact opposite. */
-   } else {
-
-/* The returned array of output indices holds the "inperm" values for the
-   selected inputs. */
-      result = astMalloc( sizeof( int )*(size_t) nin );
-      if( astOK ) {
-         for( i = 0; i < nin; i++ ) {
-            result[ i ] = PERMVAL( inp, in[ i ], npout );
-
-/* Check the input is not fed by a constant. */
-            if( result[ i ] < 0 ) {
-               result = astFree( result );
-               break;
-
-/* Check that the the output has not already been used. */
-            } else {
-               for( j = 0; j < i; j++ ) {
-                  if( result[ j ] == result[ i ] ) {
-                     result = astFree( result );
-                     break;
-                  }
-               }
-            }
-         }
-
-/* If the split was possible, the returned Mapping is a UnitMap. */
-         if( result ) *map = (AstMapping *) astUnitMap( nin, " ", status );
-      }
-   }
-
-/* If the returned Mapping has no outputs, do not return it. */
-   if( !result && *map ) {
-      *map = astAnnul( *map );
-   }
-
-/* Free returned resources if an error has occurred. */
-   if( !astOK ) {
-      result = astFree( result );
-      *map = astAnnul( *map );
-   }
-
-/* Return the list of output indices. */
-   return result;
-}
-
-static int NullPerm( AstPermMap *this, int forward, int *status ){
-/*
-*  Name:
-*     NullPerm
-
-*  Purpose:
-*     See if a PermMap transformation represents a null axis permutation.
-
-*  Type:
-*     Private function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     int NullPerm( AstPermMap *this, int forward, int *status )
-
-*  Class Membership:
-*     PermMap method
-
-*  Description:
-*     This function returns a logical value indicating if the specified
-*     transformation of the supplied PermMap is a null (i.e. unit)
-*     transformation.
-
-*  Parameters:
-*     this
-*        Pointer to the PermMap.
-*     forward
-*        Check the forward transformation? Otherise, check the inverse
-*        transformation.
-*     status
-*        Pointer to the inherited status variable.
-
-*  Returned Value:
-*     One if the specified transformation is a null axis permutation.
-*     Zero otherwise.
-
-*  Notes:
-*     - A value of zero will be returned if this function is invoked
-*     with the global error status set, or if it should fail for any
-*     reason.
-*/
-
-/* Local Variables: */
-   int i;                     /* Coordinate index */
-   int nin;                   /* Number of Mapping inputs */
-   int nout;                  /* Number of Mapping outputs */
-   int result;                /* Returned value */
-
-/* Initialise the returned result. */
-   result = 0;
-
-/* Check the global error status. */
-   if ( !astOK ) return result;
-
-/* First check the forward transformation, given by the outperm array. */
-   if( forward ) {
-
-/* If no outperm array is stored, every output is derived from the
-   corresponding input. Therefore, return 1 indicating a null axis
-   permutation. */
-      if( !this->outperm ) {
-         result = 1;
-
-/* Otherwise, check that every element in the outperm array indicates
-   that the output is derived from the input with the saem index. */
-      } else {
-         result = 1;
-         nout = astGetNout( this );
-         for( i = 0; i < nout; i++ ) {
-            if( this->outperm[ i ] != i ) {
-               result = 0;
-               break;
-            }
-         }
-      }
-
-/* Now check the inverse transformation, given by the inperm array. */
-   } else {
-
-/* If no inperm array is stored, every input is derived from the
-   corresponding output. Therefore, return 1 indicating a null axis
-   permutation. */
-      if( !this->inperm ) {
-         result = 1;
-
-/* Otherwise, check that every element in the inperm array indicates
-   that the input is derived from the output with the same index. */
-      } else {
-         result = 1;
-         nin = astGetNin( this );
-         for( i = 0; i < nin; i++ ) {
-            if( this->inperm[ i ] != i ) {
-               result = 0;
-               break;
-            }
-         }
-      }
-   }
-
-/* If an error has occurred, return zero. */
-   if( !astOK ) result = 0;
-
-/* Return the result. */
-   return result;
-}
-
-static double Rate( AstMapping *this, double *at, int ax1, int ax2, int *status ){
-/*
-*  Name:
-*     Rate
-
-*  Purpose:
-*     Calculate the rate of change of a Mapping output.
-
-*  Type:
-*     Private function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     result = Rate( AstMapping *this, double *at, int ax1, int ax2, int *status )
-
-*  Class Membership:
-*     PermMap member function (overrides the astRate method inherited
-*     from the Mapping class ).
-
-*  Description:
-*     This function returns the rate of change of a specified output of
-*     the supplied Mapping with respect to a specified input, at a
-*     specified input position.
-
-*  Parameters:
-*     this
-*        Pointer to the Mapping to be applied.
-*     at
-*        The address of an array holding the axis values at the position
-*        at which the rate of change is to be evaluated. The number of
-*        elements in this array should equal the number of inputs to the
-*        Mapping.
-*     ax1
-*        The index of the Mapping output for which the rate of change is to
-*        be found (output numbering starts at 0 for the first output).
-*     ax2
-*        The index of the Mapping input which is to be varied in order to
-*        find the rate of change (input numbering starts at 0 for the first
-*        input).
-*     status
-*        Pointer to the inherited status variable.
-
-*  Returned Value:
-*     The rate of change of Mapping output "ax1" with respect to input
-*     "ax2", evaluated at "at", or AST__BAD if the value cannot be
-*     calculated.
-
-*/
-
-/* Local Variables: */
-   AstPermMap *map;
-   int *outperm;
-   int result;
-
-/* Check inherited status */
-   if( !astOK ) return AST__BAD;
-
-/* Get a pointer to the PermMap structure. */
-   map = (AstPermMap *) this;
-
-/* Obtain a pointer to the appropriate output coordinate permutation array,
-   according to whether the PermMap has been inverted. If the specified
-   output is derived from the specified input then the rate is unity.
-   Otherwise it is zero. */
-   outperm = astGetInvert( this ) ? map->inperm : map->outperm;
-   if( outperm ) {
-      result = ( ax2 == outperm[ ax1 ] ) ? 1.0 : 0.0;
-   } else {
-      result = ( ax2 == ax1 ) ? 1.0 : 0.0;
-   }
-
-   return result;
-}
-
-static AstPointSet *Transform( AstMapping *map, AstPointSet *in,
-                               int forward, AstPointSet *out, int *status ) {
-/*
-*  Name:
-*     Transform
-
-*  Purpose:
-*     Apply a PermMap to transform a set of points.
-
-*  Type:
-*     Private function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     AstPointSet *Transform( AstMapping *map, AstPointSet *in,
-*                             int forward, AstPointSet *out, int *status )
-
-*  Class Membership:
-*     PermMap member function (over-rides the astTransform method inherited
-*     from the Mapping class).
-
-*  Description:
-*     This function takes a PermMap and a set of points encapsulated in a
-*     PointSet and transforms the points so as to apply the required coordinate
-*     permutation.
-
-*  Parameters:
-*     map
-*        Pointer to the PermMap.
-*     in
-*        Pointer to the PointSet holding the input coordinate data.
-*     forward
-*        A non-zero value indicates that the forward coordinate transformation
-*        should be applied, while a zero value requests the inverse
-*        transformation.
-*     out
-*        Pointer to a PointSet which will hold the transformed (output)
-*        coordinate values. A NULL value may also be given, in which case a
-*        new PointSet will be created by this function.
-*     status
-*        Pointer to the inherited status variable.
-
-*  Returned Value:
-*     Pointer to the output (possibly new) PointSet.
-
-*  Notes:
-*     -  A null pointer will be returned if this function is invoked with the
-*     global error status set, or if it should fail for any reason.
-*     -  The number of coordinate values per point in the input PointSet must
-*     match the number of coordinates for the PermMap being applied.
-*     -  If an output PointSet is supplied, it must have space for sufficient
-*     number of points and coordinate values per point to accommodate the
-*     result. Any excess space will be ignored.
-*/
-
-/* Local Variables: */
-   AstPermMap *this;             /* Pointer to PermMap to be applied */
-   AstPointSet *result;          /* Pointer to output PointSet */
-   double **ptr_in;              /* Pointer to input coordinate data */
-   double **ptr_out;             /* Pointer to output coordinate data */
-   double constant;              /* Constant coordinate value */
-   int *perm;                    /* Pointer to permutation array */
-   int coord;                    /* Loop counter for coordinates */
-   int maxperm;                  /* Max value in permutation array */
-   int ncoord_in;                /* Number of coordinates per input point */
-   int ncoord_out;               /* Number of coordinates per output point */
-   int npoint;                   /* Number of points */
-   int p;                        /* Permuted coordinate index */
-   int point;                    /* Loop counter for points */
-
-/* Check the global error status. */
-   if ( !astOK ) return NULL;
-
-/* Obtain a pointer to the PermMap. */
-   this = (AstPermMap *) map;
-
-/* Apply the parent mapping using the stored pointer to the Transform member
-   function inherited from the parent Mapping class. This function validates
-   all arguments and generates an output PointSet if necessary, but does not
-   actually transform any coordinate values. */
-   result = (*parent_transform)( map, in, forward, out, status );
-
-/* We will now extend the parent astTransform method by performing the
-   permutation needed to generate the output coordinate values. */
-
-/* Determine the numbers of points and coordinates per point from the input
-   and output PointSets and obtain pointers for accessing the input and output
-   coordinate values. */
-   ncoord_in = astGetNcoord( in );
-   ncoord_out = astGetNcoord( result );
-   npoint = astGetNpoint( in );
-   ptr_in = astGetPoints( in );
-   ptr_out = astGetPoints( result );
-
-/* Obtain a pointer to the appropriate coordinate permutation array, according
-   to the direction of transformation required and whether the PermMap has
-   been inverted. Also get the maximum allowed value in the permutation array. */
-   if ( ( astGetInvert( this ) != 0 ) == ( forward != 0 ) ) {
-      perm = this->inperm;
-      maxperm = ncoord_out;
-   } else {
-      perm = this->outperm;
-      maxperm = ncoord_in;
-   }
-
-/* Perform coordinate permutation. */
-/* ------------------------------- */
-   if ( astOK ) {
-
-/* Loop to generate values for each output coordinate. */
-      for ( coord = 0; coord < ncoord_out; coord++ ) {
-
-/* If the permutation array is not NULL, use it to look up which input
-   coordinate to use. Otherwise, use the corresponding input coordinate. */
-         p = PERMVAL( perm, coord, maxperm );
-
-/* If a valid input coordinate has been identified, simply copy the required
-   coordinate values from input to output. */
-         if ( ( p >= 0 ) && ( p < ncoord_in ) ) {
-            (void) memcpy( ptr_out[ coord ], ptr_in[ p ],
-                           sizeof( double ) * (size_t) npoint );
-
-/* If the permuted coordinate index is negative, use it to index the "constant"
-   array to obtain a constant value to assign. If this array is NULL, use
-   AST__BAD as the constant. */
-	 } else if ( p < 0 ) {
-            constant = this->constant ? this->constant[ (-p) - 1 ] : AST__BAD;
-
-/* Assign the constant value to the output coordinate for all points. */
-            for ( point = 0; point < npoint; point++ ) {
-               ptr_out[ coord ][ point ] = constant;
-	    }
-
-/* In all other cases, simply assign the value AST__BAD to the output
-   coordinate for all points. */
-	 } else {
-            for ( point = 0; point < npoint; point++ ) {
-               ptr_out[ coord ][ point ] = AST__BAD;
-	    }
-	 }
-      }
-   }
-
-/* Return a pointer to the output PointSet. */
-   return result;
-}
-
-/* Functions which access class attributes. */
-/* ---------------------------------------- */
-/*
-*att+
-*  Name:
-*     PermSplit
-
-*  Purpose:
-*     The method to use when splitting a PermMap using astMapSplit.
-
-*  Type:
-*     Protected attribute.
-
-*  Synopsis:
-*     Integer.
-
-*  Description:
-*     This attribute controls the behaviour of the implementation of the
-*     astMapSplit method provided by the PermMap class. If set to zero (the
-*     default), astMapSplit will split PermMaps according to the public
-*     documentation for the method. If set non-zero, the forward transformation
-*     of the PermMap defined by the "outperm" array will be ignored.
-*     Instead, the forward transformation is assumed to be the exact
-*     inverse of the inverse transformation. The Mapping returned will
-*     then be a UnitMap with Nin equal to the number of picked inputs,
-*     and the returned array of output indices will hold the "inperm"
-*     values for the picked inputs. Note, if any of these "inperm" values
-*     are negative (indicating that the inverse transformation supplies a
-*     constant value for the input), or if more than one of the selected
-*     inputs are fed (by the inverse transformation) by the same output,
-*     then the PermMap cannot be split.
-*
-*     Note, unlike most Mapping attributes, the value of this attribute
-*     may be changed at any time. This is because it does not change the
-*     nature of either the forward or inverse transformation of the Mapping.
-
-*  Applicability:
-*     PermMap
-*        All PermMaps have this attribute.
-*att-
-*/
-astMAKE_CLEAR(PermMap,PermSplit,permsplit,-INT_MAX)
-astMAKE_GET(PermMap,PermSplit,int,0,( this->permsplit != -INT_MAX ?
-                                      this->permsplit : 0 ))
-astMAKE_SET(PermMap,PermSplit,int,permsplit,( value != 0 ))
-astMAKE_TEST(PermMap,PermSplit,( this->permsplit != -INT_MAX ))
-
-
-/* Copy constructor. */
-/* ----------------- */
-static void Copy( const AstObject *objin, AstObject *objout, int *status ) {
-/*
-*  Name:
-*     Copy
-
-*  Purpose:
-*     Copy constructor for PermMap objects.
-
-*  Type:
-*     Private function.
-
-*  Synopsis:
-*     void Copy( const AstObject *objin, AstObject *objout, int *status )
-
-*  Description:
-*     This function implements the copy constructor for PermMap objects.
-
-*  Parameters:
-*     objin
-*        Pointer to the object to be copied.
-*     objout
-*        Pointer to the object being constructed.
-*     status
-*        Pointer to the inherited status variable.
-
-*  Returned Value:
-*     void
-
-*  Notes:
-*     -  This constructor makes a deep copy.
-*/
-
-/* Local Variables: */
-   AstPermMap *in;               /* Pointer to input PermMap */
-   AstPermMap *out;              /* Pointer to output PermMap */
-
-/* Check the global error status. */
-   if ( !astOK ) return;
-
-/* Obtain pointers to the input and output PermMaps. */
-   in = (AstPermMap *) objin;
-   out = (AstPermMap *) objout;
-
-/* For safety, first clear any references to the input memory from
-   the output PermMap. */
-   out->inperm = NULL;
-   out->outperm = NULL;
-   out->constant = NULL;
-
-/* For each input array which is not NULL, make a copy in allocated memory,
-   storing a pointer to it in the output PermMap structure. */
-   if ( in->inperm ) out->inperm = astStore( NULL, in->inperm,
-                                             astSizeOf( in->inperm ) );
-   if ( in->outperm ) out->outperm = astStore( NULL, in->outperm,
-                                               astSizeOf( in->outperm ) );
-   if ( in->constant ) out->constant = astStore( NULL, in->constant,
-                                                 astSizeOf( in->constant ) );
-
-/* If an error occurred, clean up by freeing all memory allocated above. */
-   if ( !astOK ) {
-      out->inperm = astFree( out->inperm );
-      out->outperm = astFree( out->outperm );
-      out->constant = astFree( out->constant );
-   }
-}
-
-/* Destructor. */
-/* ----------- */
-static void Delete( AstObject *obj, int *status ) {
-/*
-*  Name:
-*     Delete
-
-*  Purpose:
-*     Destructor for PermMap objects.
-
-*  Type:
-*     Private function.
-
-*  Synopsis:
-*     void Delete( AstObject *obj, int *status )
-
-*  Description:
-*     This function implements the destructor for PermMap objects.
-
-*  Parameters:
-*     obj
-*        Pointer to the object to be deleted.
-*     status
-*        Pointer to the inherited status variable.
-
-*  Returned Value:
-*     void
-
-*  Notes:
-*     This function attempts to execute even if the global error status is
-*     set.
-*/
-
-/* Local Variables: */
-   AstPermMap *this;             /* Pointer to PermMap */
-
-/* Obtain a pointer to the PermMap structure. */
-   this = (AstPermMap *) obj;
-
-/* Free all memory allocated by the PermMap. */
-   this->inperm = astFree( this->inperm );
-   this->outperm = astFree( this->outperm );
-   this->constant = astFree( this->constant );
-}
-
-/* Dump function. */
-/* -------------- */
-static void Dump( AstObject *this_object, AstChannel *channel, int *status ) {
-/*
-*  Name:
-*     Dump
-
-*  Purpose:
-*     Dump function for PermMap objects.
-
-*  Type:
-*     Private function.
-
-*  Synopsis:
-*     void Dump( AstObject *this, AstChannel *channel, int *status )
-
-*  Description:
-*     This function implements the Dump function which writes out data
-*     for the PermMap class to an output Channel.
-
-*  Parameters:
-*     this
-*        Pointer to the PermMap whose data are being written.
-*     channel
-*        Pointer to the Channel to which the data are being written.
-*     status
-*        Pointer to the inherited status variable.
-*/
-
-/* Local Constants: */
-#define COMMENT_LEN 150          /* Maximum length of a comment string */
-#define KEY_LEN 50               /* Maximum length of a keyword */
-
-/* Local Variables: */
-   AstPermMap *this;             /* Pointer to the PermMap structure */
-   char comment[ COMMENT_LEN + 1 ]; /* Buffer for comment strings */
-   char key[ KEY_LEN + 1 ];      /* Buffer for keyword strings */
-   int coord;                    /* Loop counter for coordinates */
-   int iconst;                   /* Loop counter for constants */
-   int invert;                   /* Invert attribute value */
-   int ival;                     /* Integer value */
-   int nconst;                   /* Number of constants */
-   int nin;                      /* Number of input coordinates */
-   int nout;                     /* Number of output coordinates */
-   int set;                      /* Value is "set"? */
-
-/* Check the global error status. */
-   if ( !astOK ) return;
-
-/* Obtain a pointer to the PermMap structure. */
-   this = (AstPermMap *) this_object;
-
-/* Determine if the PermMap is inverted and obtain the "true" number
-   of input and output coordinates by un-doing the effects of any
-   inversion. */
-   invert = astGetInvert( this );
-   nin = !invert ? astGetNin( this ) : astGetNout( this );
-   nout = !invert ? astGetNout( this ) : astGetNin( this );
-
-/* Initialise the count of constants in use. */
-   nconst = 0;
-
-/* Write out values representing the instance variables for the
-   PermMap class.  Accompany these with appropriate comment strings,
-   possibly depending on the values being written.*/
-
-/* In the case of attributes, we first use the appropriate (private)
-   Test...  member function to see if they are set. If so, we then use
-   the (private) Get... function to obtain the value to be written
-   out.
-
-   For attributes which are not set, we use the astGet... method to
-   obtain the value instead. This will supply a default value
-   (possibly provided by a derived class which over-rides this method)
-   which is more useful to a human reader as it corresponds to the
-   actual default attribute value.  Since "set" will be zero, these
-   values are for information only and will not be read back. */
-
-/* PermSplit */
-/* --------- */
-   set = TestPermSplit( this, status );
-   ival = set ? GetPermSplit( this, status ) : astGetPermSplit( this );
-   astWriteInt( channel, "pmsplt", set, 0, ival,
-                ival ? "Use alternative astMapSplit implementation" :
-                       "Use normal astMapSplit implementation" );
-
-/* "outperm" array contents. */
-/* ------------------------- */
-/* Write the boolean "OutCpy" value to indicate if output coordinates
-   are obtained simply by copying corresponding input
-   coordinates. This will be the case if "this->outperm" is NULL. */
-   ival = this->outperm ? 0 : 1;
-   set = ( ival != 0 );
-   astWriteInt( channel, "OutCpy", set, 0, ival,
-                ival ? "Output coordinates = input coordinates" :
-                       "Output coordinates specified individually" );
-
-/* If output coordinates are specified individually, create a keyword
-   for each element of the "outperm" array. */
-   if ( this->outperm ) {
-      for ( coord = 0; coord < nout; coord++ ) {
-         (void) sprintf( key, "Out%d", coord + 1 );
-
-/* Obtain the array value. If it refers to a coordinate that does not
-   exist, change the value to zero (indicating a "bad" value for this
-   coordinate). Create an appropriate comment. */
-         ival = this->outperm[ coord ];
-         if ( ival >= nin ) {
-            ival = 0;
-            (void) sprintf( comment, "Output coordinate %d is \"bad\"",
-                            coord + 1 );
-
-/* If the coordinate reference is valid, convert to 1-based coordinate
-   numbering and create an appropriate comment. */
-         } else if ( ival >= 0 ) {
-            ival++;
-            (void) sprintf( comment,
-                            "Output coordinate %d = input coordinate %d",
-                            coord + 1, ival );
-
-/* If the reference is to a constant, create an appropriate comment
-   (which depends on whether there are any constants). */
-         } else {
-            if ( this->constant ) {
-               (void) sprintf( comment,
-                               "Output coordinate %d = constant no. %d",
-                               coord + 1, -ival );
-            } else {
-               (void) sprintf( comment, "Output coordinate %d is \"bad\"",
-                               coord + 1 );
-            }
-
-/* Update the top constant number referenced. */
-            if ( nconst < -ival ) nconst = -ival;
-         }
-
-/* Write out the array value with accompanying comment. */
-         astWriteInt( channel, key, 1, 1, ival, comment );
-      }
-   }
-
-/* "inperm" array contents. */
-/* ------------------------ */
-/* Write the boolean "InCpy" value to indicate if input coordinates
-   are obtained simply by copying corresponding output
-   coordinates. This will be the case if "this->inperm" is NULL. */
-   ival = this->inperm ? 0 : 1;
-   set = ( ival != 0 );
-   astWriteInt( channel, "InCpy", set, 0, ival,
-                ival ? "Input coordinates = output coordinates" :
-                       "Input coordinates specified individually" );
-
-/* If input coordinates are specified individually, create a keyword
-   for each element of the "inperm" array. */
-   if ( this->inperm ) {
-      for ( coord = 0; coord < nin; coord++ ) {
-         (void) sprintf( key, "In%d", coord + 1 );
-
-/* Obtain the array value. If it refers to a coordinate that does not
-   exist, change the value to zero (indicating a "bad" value for this
-   coordinate). Create an appropriate comment. */
-         ival = this->inperm[ coord ];
-         if ( ival >= nout ) {
-            ival = 0;
-            (void) sprintf( comment, "Input coordinate %d is \"bad\"",
-                            coord + 1 );
-
-/* If the coordinate reference is valid, convert to 1-based coordinate
-   numbering and create an appropriate comment. */
-         } else if ( ival >= 0 ) {
-            ival++;
-            (void) sprintf( comment,
-                            "Input coordinate %d = output coordinate %d",
-                            coord + 1, ival );
-
-/* If the reference is to a constant, create an appropriate comment
-   (which depends on whether there are any constants). */
-         } else {
-            if ( this->constant ) {
-               (void) sprintf( comment,
-                               "Input coordinate %d = constant no. %d",
-                               coord + 1, -ival );
-            } else {
-               (void) sprintf( comment, "Input coordinate %d is \"bad\"",
-                               coord + 1 );
-            }
-
-/* Update the top constant number referenced. */
-            if ( nconst < -ival ) nconst = -ival;
-         }
-
-/* Write out the array value with accompanying comment. */
-         astWriteInt( channel, key, 1, 1, ival, comment );
-      }
-   }
-
-/* Number of constants. */
-/* -------------------- */
-/* First check if there are any constants, then write out how many
-   there are. */
-   if ( !this->constant ) nconst = 0;
-   set = ( nconst != 0 );
-   astWriteInt( channel, "Nconst", set, 0, nconst, "Number of constants" );
-
-/* Constants. */
-/* ---------- */
-/* Loop to create a keyword and comment for each constant. */
-   for ( iconst = 0; iconst < nconst; iconst++ ) {
-      (void) sprintf( key, "Con%d", iconst + 1 );
-      (void) sprintf( comment, "Constant number %d", iconst + 1 );
-
-/* Write out each constant value and comment. */
-      set = ( this->constant[ iconst ] != AST__BAD );
-      if ( set ) {
-         astWriteDouble( channel, key, 1, 1, this->constant[ iconst ],
-                         comment );
-      } else {
-         astWriteString( channel, key, 0, 1, "<bad>", comment );
-      }
-   }
-
-/* Undefine macros local to this function. */
-#undef COMMENT_LEN
-#undef KEY_LEN
-}
-
-/* Standard class functions. */
-/* ========================= */
-/* Implement the astIsAPermMap and astCheckPermMap functions using the macros
-   defined for this purpose in the "object.h" header file. */
-astMAKE_ISA(PermMap,Mapping)
-astMAKE_CHECK(PermMap)
-
-AstPermMap *astPermMap_( int nin, const int inperm[], int nout,
-                         const int outperm[], const double constant[],
-                         const char *options, int *status, ...) {
-/*
-*++
-*  Name:
-c     astPermMap
-f     AST_PERMMAP
-
-*  Purpose:
-*     Create a PermMap.
-
-*  Type:
-*     Public function.
-
-*  Synopsis:
-c     #include "permmap.h"
-c     AstPermMap *astPermMap( int nin, const int inperm[], int nout,
-c                             const int outperm[], double constant[],
-c                             const char *options, ... )
-f     RESULT = AST_PERMMAP( NIN, INPERM, NOUT, OUTPERM, CONSTANT, OPTIONS,
-f                           STATUS )
-
-*  Class Membership:
-*     PermMap constructor.
-
-*  Description:
-*     This function creates a new PermMap and optionally initialises its
-*     attributes.
-*
-*     A PermMap is a Mapping which permutes the order of coordinates,
-*     and possibly also changes the number of coordinates, between its
-*     input and output.
-*
-*     In addition to permuting the coordinate order, a PermMap may
-*     also assign constant values to coordinates. This is useful when
-*     the number of coordinates is being increased as it allows fixed
-*     values to be assigned to any new ones.
-
-*  Parameters:
-c     nin
-f     NIN = INTEGER (Given)
-*        The number of input coordinates.
-c     inperm
-f     INPERM = INTEGER( NIN ) (Given)
-c        An optional array with "nin" elements which, for each input
-f        An array which, for each input
-*        coordinate, should contain the number of the output
-*        coordinate whose value is to be used (note that this array
-*        therefore defines the inverse coordinate transformation).
-*        Coordinates are numbered starting from 1.
-*
-*        For details of additional special values that may be used in
-c        this array, see the description of the "constant" parameter.
-f        this array, see the description of the CONSTANT argument.
-c
-c        If a NULL pointer is supplied instead of an array, each input
-c        coordinate will obtain its value from the corresponding
-c        output coordinate (or will be assigned the value AST__BAD if
-c        there is no corresponding output coordinate).
-c     nout
-f     NOUT = INTEGER (Given)
-*        The number of output coordinates.
-c     outperm
-f     OUTPERM = INTEGER( NOUT ) (Given)
-c        An optional array with "nout" elements which, for each output
-f        An array which, for each output
-*        coordinate, should contain the number of the input coordinate
-*        whose value is to be used (note that this array therefore
-*        defines the forward coordinate transformation).  Coordinates
-*        are numbered starting from 1.
-*
-*        For details of additional special values that may be used in
-c        this array, see the description of the "constant" parameter.
-f        this array, see the description of the CONSTANT argument.
-c
-c        If a NULL pointer is supplied instead of an array, each output
-c        coordinate will obtain its value from the corresponding
-c        input coordinate (or will be assigned the value AST__BAD if
-c        there is no corresponding input coordinate).
-c     constant
-f     CONSTANT = DOUBLE PRECISION( * ) (Given)
-c        An optional array containing values which may be assigned to
-f        An array containing values which may be assigned to
-*        input and/or output coordinates instead of deriving them
-c        from other coordinate values. If either of the "inperm" or
-f        from other coordinate values. If either of the INPERM or
-c        "outperm" arrays contains a negative value, it is used to
-f        OUTPERM arrays contains a negative value, it is used to
-c        address this "constant" array (such that -1 addresses the
-f        address this CONSTANT array (such that -1 addresses the
-*        first element, -2 addresses the second element, etc.) and the
-*        value obtained is used as the corresponding coordinate value.
-*
-*        Care should be taken to ensure that locations lying outside
-*        the extent of this array are not accidentally addressed. The
-c        array is not used if the "inperm" and "outperm" arrays do not
-f        array is not used if the INPERM and OUTPERM arrays do not
-*        contain negative values.
-c
-c        If a NULL pointer is supplied instead of an array, the
-c        behaviour is as if the array were of infinite length and
-c        filled with the value AST__BAD.
-c     options
-f     OPTIONS = CHARACTER * ( * ) (Given)
-c        Pointer to a null-terminated string containing an optional
-c        comma-separated list of attribute assignments to be used for
-c        initialising the new PermMap. The syntax used is identical to
-c        that for the astSet function and may include "printf" format
-c        specifiers identified by "%" symbols in the normal way.
-f        A character string containing an optional comma-separated
-f        list of attribute assignments to be used for initialising the
-f        new PermMap. The syntax used is identical to that for the
-f        AST_SET routine.
-c     ...
-c        If the "options" string contains "%" format specifiers, then
-c        an optional list of additional arguments may follow it in
-c        order to supply values to be substituted for these
-c        specifiers. The rules for supplying these are identical to
-c        those for the astSet function (and for the C "printf"
-c        function).
-f     STATUS = INTEGER (Given and Returned)
-f        The global status.
-
-*  Returned Value:
-c     astPermMap()
-f     AST_PERMMAP = INTEGER
-*        A pointer to the new PermMap.
-
-*  Notes:
-c     - If either of the "inperm" or "outperm" arrays contains a
-f     - If either of the INPERM or OUTPERM arrays contains a
-*     zero value (or a positive value which does not identify a valid
-*     output/input coordinate, as appropriate), then the value
-*     AST__BAD is assigned as the new coordinate value.
-*     - This function does not attempt to ensure that the forward and
-*     inverse transformations performed by the PermMap are
-*     self-consistent in any way. You are therefore free to supply
-*     coordinate permutation arrays that achieve whatever effect is
-*     desired.
-*     - A null Object pointer (AST__NULL) will be returned if this
-c     function is invoked with the AST error status set, or if it
-f     function is invoked with STATUS set to an error value, or if it
-*     should fail for any reason.
-*--
-*/
-
-/* Local Variables: */
-   astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
-   AstPermMap *new;              /* Pointer to new PermMap */
-   va_list args;                 /* Variable argument list */
-
-/* Get a pointer to the thread specific global data structure. */
-   astGET_GLOBALS(NULL);
-
-/* Check the global status. */
-   if ( !astOK ) return NULL;
-
-/* Initialise the PermMap, allocating memory and initialising the
-   virtual function table as well if necessary. */
-   new = astInitPermMap( NULL, sizeof( AstPermMap ), !class_init, &class_vtab,
-                         "PermMap", nin, inperm, nout, outperm, constant );
-
-/* If successful, note that the virtual function table has been
-   initialised. */
-   if ( astOK ) {
-      class_init = 1;
-
-/* Obtain the variable argument list and pass it along with the options string
-   to the astVSet method to initialise the new PermMap's attributes. */
-      va_start( args, status );
-      astVSet( new, options, NULL, args );
-      va_end( args );
-
-/* If an error occurred, clean up by deleting the new object. */
-      if ( !astOK ) new = astDelete( new );
-   }
-
-/* Return a pointer to the new PermMap. */
-   return new;
-}
-
-AstPermMap *astPermMapId_( int nin, const int inperm[], int nout,
-                           const int outperm[], const double constant[],
-                           const char *options, ... ) {
-/*
-*  Name:
-*     astPermMapId_
-
-*  Purpose:
-*     Create a PermMap.
-
-*  Type:
-*     Private function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     AstPermMap *astPermMapId_( int nin, const int inperm[], int nout,
-*                                const int outperm[], const double constant[],
-*                                const char *options, ... )
-
-*  Class Membership:
-*     PermMap constructor.
-
-*  Description:
-*     This function implements the external (public) interface to the
-*     astPermMap constructor function. It returns an ID value (instead
-*     of a true C pointer) to external users, and must be provided
-*     because astPermMap_ has a variable argument list which cannot be
-*     encapsulated in a macro (where this conversion would otherwise
-*     occur).
-*
-*     This function also converts the coordinate numbering in the
-*     permutation arrays from 1-based (used externally) to zero-based
-*     (used internally).
-*
-*     The variable argument list also prevents this function from
-*     invoking astPermMap_ directly, so it must be a re-implementation
-*     of it in all respects, except for the final conversion of the
-*     result to an ID value.
-
-*  Parameters:
-*     As for astPermMap_.
-
-*  Returned Value:
-*     The ID value associated with the new PermMap.
-*/
-
-/* Local Variables: */
-   astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
-   AstPermMap *new;              /* Pointer to new PermMap */
-   int *inperm1;                 /* Pointer to temporary copy of "inperm" */
-   int *outperm1;                /* Pointer to temporary copy of "outperm" */
-   int coord;                    /* Loop counter for coordinates */
-
-/* Variable argument list */
-   va_list args;                 /* Get a pointer to the thread specific global data structure. */
-
-   int *status;                  /* Pointer to inherited status value */
-
-   astGET_GLOBALS(NULL);
-
-/* Get a pointer to the inherited status value. */
-   status = astGetStatusPtr;
-
-/* Check the global status. */
-   if ( !astOK ) return NULL;
-
-/* If the "nin" and "nout" values are acceptable, allocate memory to
-   hold temporary copies of the "inperm" and "outperm" arrays (but
-   only if these arrays are not NULL). */
-   inperm1 = NULL;
-   outperm1 = NULL;
-   if ( ( nin >= 0 ) && ( nout >= 0 ) ) {
-      if ( inperm ) inperm1 = astMalloc( sizeof( int ) * (size_t) nin );
-      if ( outperm ) outperm1 = astMalloc( sizeof( int ) * (size_t) nout );
-      if ( astOK ) {
-
-/* If necessary, make a copy of the "inperm" array, converting any
-   zero values into (zero-based) coordinate numbers that do not exist,
-   indicating a "bad" coordinate value. */
-         if ( inperm ) {
-            for ( coord = 0; coord < nin; coord++ ) {
-               if ( inperm[ coord ] < 0 ) {
-                  inperm1[ coord ] = inperm[ coord ];
-               } else if ( inperm[ coord ] == 0 ) {
-                  inperm1[ coord ] = nout;
-
-/* Convert valid coordinate references from 1-based (used externally)
-   to zero-based (used internally). */
-               } else {
-                  inperm1[ coord ] = inperm[ coord ] - 1;
-               }
-            }
-         }
-
-/* Repeat this process on the "outperm" array. */
-         if ( outperm ) {
-            for ( coord = 0; coord < nout; coord++ ) {
-               if ( outperm[ coord ] < 0 ) {
-                  outperm1[ coord ] = outperm[ coord ];
-               } else if ( outperm[ coord ] == 0 ) {
-                  outperm1[ coord ] = nin;
-               } else {
-                  outperm1[ coord ] = outperm[ coord ] - 1;
-               }
-            }
-         }
-      }
-   }
-
-/* Initialise the PermMap, allocating memory and initialising the
-   virtual function table as well if necessary. */
-   new = astInitPermMap( NULL, sizeof( AstPermMap ), !class_init, &class_vtab,
-                         "PermMap", nin, inperm1, nout, outperm1, constant );
-
-/* If necessary, free the temporary arrays allocated above. */
-   if ( ( nin >= 0 ) && ( nout >= 0 ) ) {
-      if ( inperm ) inperm1 = astFree( inperm1 );
-      if ( outperm ) outperm1 = astFree( outperm1 );
-   }
-
-/* If successful, note that the virtual function table has been
-   initialised. */
-   if ( astOK ) {
-      class_init = 1;
-
-/* Obtain the variable argument list and pass it along with the options string
-   to the astVSet method to initialise the new PermMap's attributes. */
-      va_start( args, options );
-      astVSet( new, options, NULL, args );
-      va_end( args );
-
-/* If an error occurred, clean up by deleting the new object. */
-      if ( !astOK ) new = astDelete( new );
-   }
-
-/* Return an ID value for the new PermMap. */
-   return astMakeId( new );
-}
-
-AstPermMap *astInitPermMap_( void *mem, size_t size, int init,
-                             AstPermMapVtab *vtab, const char *name,
-                             int nin, const int inperm[],
-                             int nout, const int outperm[],
-                             const double constant[], int *status ) {
-/*
-*+
-*  Name:
-*     astInitPermMap
-
-*  Purpose:
-*     Initialise a PermMap.
-
-*  Type:
-*     Protected function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     AstPermMap *astInitPermMap( void *mem, size_t size, int init,
-*                                 AstPermMapVtab *vtab, const char *name,
-*                                 int nin, const int inperm[],
-*                                 int nout, const int outperm[],
-*                                 const double constant[] )
-
-*  Class Membership:
-*     PermMap initialiser.
-
-*  Description:
-*     This function is provided for use by class implementations to initialise
-*     a new PermMap object. It allocates memory (if necessary) to accommodate
-*     the PermMap plus any additional data associated with the derived class.
-*     It then initialises a PermMap structure at the start of this memory. If
-*     the "init" flag is set, it also initialises the contents of a virtual
-*     function table for a PermMap at the start of the memory passed via the
-*     "vtab" parameter.
-
-*  Parameters:
-*     mem
-*        A pointer to the memory in which the PermMap is to be initialised.
-*        This must be of sufficient size to accommodate the PermMap data
-*        (sizeof(PermMap)) plus any data used by the derived class. If a value
-*        of NULL is given, this function will allocate the memory itself using
-*        the "size" parameter to determine its size.
-*     size
-*        The amount of memory used by the PermMap (plus derived class data).
-*        This will be used to allocate memory if a value of NULL is given for
-*        the "mem" parameter. This value is also stored in the PermMap
-*        structure, so a valid value must be supplied even if not required for
-*        allocating memory.
-*     init
-*        A logical flag indicating if the PermMap's virtual function table is
-*        to be initialised. If this value is non-zero, the virtual function
-*        table will be initialised by this function.
-*     vtab
-*        Pointer to the start of the virtual function table to be associated
-*        with the new PermMap.
-*     name
-*        Pointer to a constant null-terminated character string which contains
-*        the name of the class to which the new object belongs (it is this
-*        pointer value that will subsequently be returned by the Object
-*        astClass function).
-*     nin
-*        The number of input coordinate values per point.
-*     inperm
-*        Pointer to an array of int, with nin elements. For each input
-*        coordinate, the corresponding element of this array should contain the
-*        (zero-based) index of the output coordinate whose value is to be used.
-*        (Note that this array therefore defines the inverse coordinate
-*        transformation.) If a NULL value is supplied, the corresponding output
-*        coordinate value is used (or AST__BAD if there is no corresponding
-*        output coordinate).
-*
-*        For details of additional special values that may be used in this
-*        array, see the description of the "constant" parameter.
-*     nout
-*        The number of output coordinate values per point.
-*     outperm
-*        Pointer to an array of int, with nout elements. For each output
-*        coordinate, the corresponding element of this array should contain the
-*        (zero-based) index of the input coordinate whose value is to be used.
-*        (Note that this array therefore defines the forward coordinate
-*        transformation.) If a NULL value is supplied, the corresponding input
-*        coordinate value is used (or AST__BAD if there is no corresponding
-*        input coordinate).
-*
-*        For details of additional special values that may be used in this
-*        array, see the description of the "constant" parameter.
-*     constant
-*        Pointer to an array of double, which contains optional values which
-*        may be assigned to input and/or output coordinate values (instead of
-*        deriving them from other coordinate values). If either of the
-*        "inperm" or "outperm" arrays contains a negative value, it is used to
-*        address this "constant" array (such that -1 addresses the first
-*        element, -2 addresses the second element, etc.) and the value obtained
-*        is used as the corresponding coordinate value. Care should be taken
-*        to ensure that locations lying outside the extent of this array are
-*        not accidentally addressed.
-*
-*        If a NULL value is supplied for this parameter, the behaviour is as
-*        if the constant array were of infinite length and filled with the
-*        value AST__BAD.
-
-*  Returned Value:
-*     A pointer to the new PermMap.
-
-*  Notes:
-*     -  This function does not attempt to ensure that the forward and inverse
-*     transformations performed by the resulting PermMap are consistent in any
-*     way. The caller is therefore free to define the permutation arrays to
-*     achieve whatever effect is desired.
-*     -  If either of the "inperm" or "outperm" arrays contains a positive
-*     value which does not identify a valid output/input coordinate (as
-*     appropriate), then the value AST__BAD is assigned as the new coordinate
-*     value.
-*     -  This function makes a copy of the contents of the arrays supplied.
-*     -  A null pointer will be returned if this function is invoked with the
-*     global error status set, or if it should fail for any reason.
-*-
-*/
-
-/* Local Variables: */
-   AstPermMap *new;              /* Pointer to new PermMap */
-   int i;                        /* Loop counter for coordinates */
-   int neg;                      /* Most negative permutation index */
-
-/* Check the global status. */
-   if ( !astOK ) return NULL;
-
-/* If necessary, initialise the virtual function table. */
-   if ( init ) astInitPermMapVtab( vtab, name );
-
-/* Initialise a Mapping structure (the parent class) as the first component
-   within the PermMap structure, allocating memory if necessary. Specify that
-   the Mapping should be defined in both the forward and inverse directions. */
-   new = (AstPermMap *) astInitMapping( mem, size, 0,
-                                        (AstMappingVtab *) vtab, name,
-                                        nin, nout, 1, 1 );
-
-   if ( astOK ) {
-
-/* Initialise the PermMap data. */
-/* ---------------------------- */
-      new->permsplit = -INT_MAX;
-
-/* Initialise the array pointers. */
-      new->inperm = NULL;
-      new->outperm = NULL;
-      new->constant = NULL;
-
-/* If an "inperm" and/or "outperm" array has been supplied, allocate memory
-   and store a copy. */
-      if ( inperm ) new->inperm = astStore( NULL, inperm, sizeof( int ) *
-                                                          (size_t) nin );
-      if ( outperm ) new->outperm = astStore( NULL, outperm, sizeof( int ) *
-                                                             (size_t) nout );
-
-/* If a "constant" array has been supplied, we must also store a copy of it,
-   but must first determine how many of its elements we need. */
-      if ( constant ) {
-
-/* Loop through the "inperm" array (if supplied) to find the most negative
-   value it contains. This corresponds with the maximum index into the
-   constant array. */
-         neg = 0;
-         if ( inperm ) {
-            for ( i = 0; i < nin; i++ ) {
-               if ( inperm[ i ] < neg ) neg = inperm[ i ];
-	    }
-	 }
-
-/* Also perform this process on the "outperm" array (if supplied). */
-         if ( outperm ) {
-            for ( i = 0; i < nout; i++ ) {
-               if ( outperm[ i ] < neg ) neg = outperm[ i ];
-	    }
-	 }
-
-/* If a negative value was found, use its size to determine how many elements
-   of the "constant" array to store in allocated memory. */
-         if ( neg < 0 ) {
-            new->constant = astStore( NULL, constant, sizeof( double ) *
-                                                      (size_t) (-neg) );
-	 }
-      }
-
-/* If an error occurred, clean up by deleting the new object. */
-      if ( !astOK ) {
-         new = astDelete( new );
-      }
-   }
-
-/* Return a pointer to the new object. */
-   return new;
-}
-
-AstPermMap *astLoadPermMap_( void *mem, size_t size,
-                             AstPermMapVtab *vtab, const char *name,
-                             AstChannel *channel, int *status ) {
-/*
-*+
-*  Name:
-*     astLoadPermMap
-
-*  Purpose:
-*     Load a PermMap.
-
-*  Type:
-*     Protected function.
-
-*  Synopsis:
-*     #include "permmap.h"
-*     AstPermMap *astLoadPermMap( void *mem, size_t size,
-*                                 AstPermMapVtab *vtab, const char *name,
-*                                 AstChannel *channel )
-
-*  Class Membership:
-*     PermMap loader.
-
-*  Description:
-*     This function is provided to load a new PermMap using data read
-*     from a Channel. It first loads the data used by the parent class
-*     (which allocates memory if necessary) and then initialises a
-*     PermMap structure in this memory, using data read from the input
-*     Channel.
-*
-*     If the "init" flag is set, it also initialises the contents of a
-*     virtual function table for a PermMap at the start of the memory
-*     passed via the "vtab" parameter.
-
-
-*  Parameters:
-*     mem
-*        A pointer to the memory into which the PermMap is to be
-*        loaded.  This must be of sufficient size to accommodate the
-*        PermMap data (sizeof(PermMap)) plus any data used by derived
-*        classes. If a value of NULL is given, this function will
-*        allocate the memory itself using the "size" parameter to
-*        determine its size.
-*     size
-*        The amount of memory used by the PermMap (plus derived class
-*        data).  This will be used to allocate memory if a value of
-*        NULL is given for the "mem" parameter. This value is also
-*        stored in the PermMap structure, so a valid value must be
-*        supplied even if not required for allocating memory.
-*
-*        If the "vtab" parameter is NULL, the "size" value is ignored
-*        and sizeof(AstPermMap) is used instead.
-*     vtab
-*        Pointer to the start of the virtual function table to be
-*        associated with the new PermMap. If this is NULL, a pointer
-*        to the (static) virtual function table for the PermMap class
-*        is used instead.
-*     name
-*        Pointer to a constant null-terminated character string which
-*        contains the name of the class to which the new object
-*        belongs (it is this pointer value that will subsequently be
-*        returned by the astGetClass method).
-*
-*        If the "vtab" parameter is NULL, the "name" value is ignored
-*        and a pointer to the string "PermMap" is used instead.
-
-*  Returned Value:
-*     A pointer to the new PermMap.
-
-*  Notes:
-*     - A null pointer will be returned if this function is invoked
-*     with the global error status set, or if it should fail for any
-*     reason.
-*-
-*/
-
-/* Local Constants: */
-   astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
-#define KEY_LEN 50               /* Maximum length of a keyword */
-
-/* Local Variables: */
-   AstPermMap *new;              /* Pointer to the new PermMap */
-   char key[ KEY_LEN + 1 ];      /* Buffer for keyword strings */
-   int coord;                    /* Loop counter for coordinates */
-   int iconst;                   /* Loop counter for constants */
-   int in_cpy;                   /* Input coordinates obtained by copying? */
-   int invert;                   /* Invert attribute value */
-   int ival;                     /* Integer value */
-   int nconst;                   /* Number of constants */
-   int nin;                      /* Number of input coordinates */
-   int nout;                     /* Number of output coordinates */
-   int out_cpy;                  /* Output coordinates obtained by copying? */
-
-/* Get a pointer to the thread specific global data structure. */
-   astGET_GLOBALS(channel);
-
-/* Initialise. */
-   new = NULL;
-
-/* Check the global error status. */
-   if ( !astOK ) return new;
-
-/* If a NULL virtual function table has been supplied, then this is
-   the first loader to be invoked for this PermMap. In this case the
-   PermMap belongs to this class, so supply appropriate values to be
-   passed to the parent class loader (and its parent, etc.). */
-   if ( !vtab ) {
-      size = sizeof( AstPermMap );
-      vtab = &class_vtab;
-      name = "PermMap";
-
-/* If required, initialise the virtual function table for this class. */
-      if ( !class_init ) {
-         astInitPermMapVtab( vtab, name );
-         class_init = 1;
-      }
-   }
-
-/* Invoke the parent class loader to load data for all the ancestral
-   classes of the current one, returning a pointer to the resulting
-   partly-built PermMap. */
-   new = astLoadMapping( mem, size, (AstMappingVtab *) vtab, name,
-                         channel );
-
-   if ( astOK ) {
-
-/* Read input data. */
-/* ================ */
-/* Request the input Channel to read all the input data appropriate to
-   this class into the internal "values list". */
-      astReadClassData( channel, "PermMap" );
-
-/* Now read each individual data item from this list and use it to
-   initialise the appropriate instance variable(s) for this class. */
-
-/* In the case of attributes, we first read the "raw" input value,
-   supplying the "unset" value as the default. If a "set" value is
-   obtained, we then use the appropriate (private) Set... member
-   function to validate and set the value properly. */
-
-/* Initialise the PermMap's pointers. */
-      new->inperm = NULL;
-      new->outperm = NULL;
-      new->constant = NULL;
-
-/* Determine if the PermMap is inverted and obtain the "true" number
-   of input and output coordinates by un-doing the effects of any
-   inversion. */
-      invert = astGetInvert( new );
-      nin = !invert ? astGetNin( new ) : astGetNout( new );
-      nout = !invert ? astGetNout( new ) : astGetNin( new );
-
-/* PermSplit. */
-/* ---------- */
-      new->permsplit = astReadInt( channel, "pmsplt", -INT_MAX );
-      if ( TestPermSplit( new, status ) ) SetPermSplit( new, new->permsplit, status );
-
-/* InCpy and OutCpy. */
-/* ----------------- */
-/* Obtain boolean values via the "InCpy" and "OutCpy" keywords which
-   indicate if input/output coordinates should be obtained simply by
-   copying the corresponding output/input coordinates. */
-      in_cpy = astReadInt( channel, "incpy", 0 );
-      out_cpy = astReadInt( channel, "outcpy", 0 );
-
-/* If coordinates are specified individually (not simply copied), then
-   allocate memory for the coordinate permutation arrays. */
-      if ( !in_cpy ) new->inperm = astMalloc( sizeof( int ) * (size_t) nin );
-      if ( !out_cpy ) new->outperm = astMalloc( sizeof( int ) *
-                                                (size_t) nout );
-
-/* If an error occurred, ensure that all allocated memory is freed. */
-      if ( !astOK ) {
-         if ( !in_cpy ) new->inperm = astFree( new->inperm );
-         if ( !out_cpy ) new->outperm = astFree( new->outperm );
-
-/* Otherwise read data into these arrays... */
-      } else {
-
-/* "inperm" array contents. */
-/* ------------------------ */
-/* If required, create a keyword for each element of the "inperm"
-   array and read the element's value. */
-         if ( !in_cpy ) {
-            for ( coord = 0; coord < nin; coord++ ) {
-               (void) sprintf( key, "in%d", coord + 1 );
-               ival = astReadInt( channel, key, 0 );
-
-/* If the value is zero (indicating a "bad" coordinate), convert it to
-   a (zero-based) coordinate number that doesn't exist. */
-               if ( ival == 0 ) {
-                  ival = nout;
-
-/* If the coordinate reference is valid, convert to zero-based
-   coordinate numbering for internal use. */
-               } else if ( ival > 0 ) {
-                  ival--;
-               }
-
-/* Store the value. */
-               new->inperm[ coord ] = ival;
-            }
-         }
-
-/* "outperm" array contents. */
-/* ------------------------- */
-/* If required, create a keyword for each element of the "outperm"
-   array and read the element's value. */
-         if ( !out_cpy ) {
-            for ( coord = 0; coord < nout; coord++ ) {
-               (void) sprintf( key, "out%d", coord + 1 );
-               ival = astReadInt( channel, key, 0 );
-
-/* If the value is zero (indicating a "bad" coordinate), convert it to
-   a (zero-based) coordinate number that doesn't exist. */
-               if ( ival == 0 ) {
-                  ival = nin;
-
-/* If the coordinate reference is valid, convert to zero-based
-   coordinate numbering for internal use. */
-               } else if ( ival > 0 ) {
-                  ival--;
-               }
-
-/* Store the value. */
-               new->outperm[ coord ] = ival;
-            }
-         }
-
-/* Number of constants. */
-/* -------------------- */
-/* Determine the number of constants and allocate memory to hold
-   them. */
-         nconst = astReadInt( channel, "nconst", 0 );
-         if ( nconst < 0 ) nconst = 0;
-         new->constant = astMalloc( sizeof( double ) * (size_t) nconst );
-         if ( astOK ) {
-
-/* Constants. */
-/* ---------- */
-/* Create a keyword for each constant and read its value. */
-            for ( iconst = 0; iconst < nconst; iconst++ ) {
-               (void) sprintf( key, "con%d", iconst + 1 );
-               new->constant[ iconst ] =
-                  astReadDouble( channel, key, AST__BAD );
-            }
-         }
-      }
-
-/* If an error occurred, clean up by deleting the new PermMap. */
-      if ( !astOK ) new = astDelete( new );
-   }
-
-/* Return the new PermMap pointer. */
-   return new;
-
-/* Undefine macros local to this function. */
-#undef KEY_LEN
-}
-
-/* Virtual function interfaces. */
-/* ============================ */
-/* These provide the external interface to the virtual functions defined by
-   this class. Each simply checks the global error status and then locates and
-   executes the appropriate member function, using the function pointer stored
-   in the object's virtual function table (this pointer is located using the
-   astMEMBER macro defined in "object.h").
-
-   Note that the member function may not be the one defined here, as it may
-   have been over-ridden by a derived class. However, it should still have the
-   same interface. */
-
-double *astGetConstants_( AstPermMap *this, int *status ){
-   if( !astOK ) return NULL;
-   return (**astMEMBER(this,PermMap,GetConstants))( this, status );
-}
-
-int *astGetInPerm_( AstPermMap *this, int *status ){
-   if( !astOK ) return NULL;
-   return (**astMEMBER(this,PermMap,GetInPerm))( this, status );
-}
-
-int *astGetOutPerm_( AstPermMap *this, int *status ){
-   if( !astOK ) return NULL;
-   return (**astMEMBER(this,PermMap,GetOutPerm))( this, status );
-}
-
-
-
-
-
-