upgrade ast 8.7.1

1 files changed, 2942 insertions, 0 deletions

diff --git a/ast/intramap.c b/ast/intramap.c
new file mode 100644
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--- /dev/null
+++ b/ast/intramap.c
@@ -0,0 +1,2942 @@
+/*
+*class++
+*  Name:
+*     IntraMap
+
+*  Purpose:
+c     Map points using a private transformation function.
+f     Map points using a private transformation routine.
+
+*  Constructor Function:
+c     astIntraMap (also see astIntraReg)
+f     AST_INTRAMAP (also see AST_INTRAREG)
+
+*  Description:
+c     The IntraMap class provides a specialised form of Mapping which
+c     encapsulates a privately-defined coordinate transformation
+c     other AST Mapping. This allows you to create Mappings that
+c     perform any conceivable coordinate transformation.
+f     The IntraMap class provides a specialised form of Mapping which
+f     encapsulates a privately-defined coordinate transformation
+f     routine (e.g. written in Fortran) so that it may be used like
+f     any other AST Mapping. This allows you to create Mappings that
+f     perform any conceivable coordinate transformation.
+*
+*     However, an IntraMap is intended for use within a single program
+*     or a private suite of software, where all programs have access
+*     to the same coordinate transformation functions (i.e. can be
+*     linked against them). IntraMaps should not normally be stored in
+*     datasets which may be exported for processing by other software,
+*     since that software will not have the necessary transformation
+*     functions available, resulting in an error.
+*
+c     You must register any coordinate transformation functions to be
+c     used using astIntraReg before creating an IntraMap.
+f     You must register any coordinate transformation functions to be
+f     used using AST_INTRAREG before creating an IntraMap.
+
+*  Inheritance:
+*     The IntraMap class inherits from the Mapping class.
+
+*  Attributes:
+*     In addition to those attributes common to all Mappings, every
+*     IntraMap also has the following attributes:
+*
+*     - IntraFlag: IntraMap identification string
+
+*  Functions:
+c     The IntraMap class does not define any new functions beyond those
+f     The IntraMap 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:
+*     16-MAR-1998 (RFWS):
+*        Original version.
+*     15-SEP-1999 (RFWS):
+*        Added a "this" pointer to the external transformation function
+*        used by an IntraMap.
+*     20-JUN-2001 (DSB):
+*        Add an "astClone" call to prevent the pointer for "this" being
+*        annulled at the end of the Transform method.
+*     8-JAN-2003 (DSB):
+*        Changed private InitVtab method to protected astInitIntraMapVtab
+*        method.
+*     7-DEC-2005 (DSB):
+*        Free memory allocated by calls to astReadString.
+*     14-FEB-2006 (DSB):
+*        Override astGetObjSize.
+*     1-MAR-2006 (DSB):
+*        Replace astSetPermMap within DEBUG blocks by astBeginPM/astEndPM.
+*     10-MAY-2006 (DSB):
+*        Override astEqual.
+*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 IntraMap
+
+/* 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 "globals.h"             /* Thread-safe global data access */
+#include "object.h"              /* Base Object class */
+#include "pointset.h"            /* Sets of points/coordinates */
+#include "mapping.h"             /* Coordinate mappings (parent class) */
+#include "channel.h"             /* I/O channels */
+#include "unitmap.h"             /* Unit (identity) Mappings */
+#include "intramap.h"            /* Interface definition for this class */
+
+/* Error code definitions. */
+/* ----------------------- */
+#include "ast_err.h"             /* AST error codes */
+
+/* C header files. */
+/* --------------- */
+#include <ctype.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+
+/* Module Variables. */
+/* ================= */
+
+/* Pointer to array of transformation function data. */
+static AstIntraMapTranData *tran_data = NULL;
+
+/* Number of transformation functions registered. */
+static int tran_nfun = 0;
+
+/* 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 used or extended by this
+   class. */
+static int (* parent_getobjsize)( AstObject *, int * );
+static AstPointSet *(* parent_transform)( AstMapping *, AstPointSet *, int, AstPointSet *, int * );
+static const char *(* parent_getattrib)( AstObject *, const char *, int * );
+static int (* parent_getnin)( AstMapping *, int * );
+static int (* parent_getnout)( AstMapping *, int * );
+static int (* parent_testattrib)( AstObject *, const char *, int * );
+static void (* parent_clearattrib)( AstObject *, const char *, int * );
+static void (* parent_setattrib)( AstObject *, const char *, int * );
+
+/* Define macros for accessing each item of thread specific global data. */
+#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(IntraMap)
+
+/* Define macros for accessing each item of thread specific global data. */
+#define class_init astGLOBAL(IntraMap,Class_Init)
+#define class_vtab astGLOBAL(IntraMap,Class_Vtab)
+
+
+/* A mutex used to serialise invocations of the IntraReg function (the
+   only function allowed to modify the contents of the static tran_data
+   array). */
+static pthread_mutex_t mutex1 = PTHREAD_MUTEX_INITIALIZER;
+#define LOCK_MUTEX1 pthread_mutex_lock( &mutex1 );
+#define UNLOCK_MUTEX1 pthread_mutex_unlock( &mutex1 );
+
+/* A mutex used to serialise invocations of extrnal transformation
+   functions (which may not be thread-safe). */
+static pthread_mutex_t mutex2 = PTHREAD_MUTEX_INITIALIZER;
+#define LOCK_MUTEX2 pthread_mutex_lock( &mutex2 );
+#define UNLOCK_MUTEX2 pthread_mutex_unlock( &mutex2 );
+
+/* If thread safety is not needed, declare and initialise globals at static
+   variables. */
+#else
+
+
+/* Define the class virtual function table and its initialisation flag
+   as static variables. */
+static AstIntraMapVtab class_vtab;   /* Virtual function table */
+static int class_init = 0;       /* Virtual function table initialised? */
+
+#define LOCK_MUTEX1
+#define UNLOCK_MUTEX1
+
+#define LOCK_MUTEX2
+#define UNLOCK_MUTEX2
+
+#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. */
+AstIntraMap *astIntraMapId_( const char *, int, int, const char *, ... );
+void astIntraRegFor_( const char *, int, int, void (* tran)( AstMapping *, int, int, const double *[], int, int, double *[] ), void (* tran_wrap)( void (*)( AstMapping *, int, int, const double *[], int, int, double *[] ), AstMapping *, int, int, const double *[], int, int, double *[], int * ), unsigned int, const char *, const char *, const char *, int * );
+
+/* Prototypes for Private Member Functions. */
+/* ======================================== */
+static AstPointSet *Transform( AstMapping *, AstPointSet *, int, AstPointSet *, int * );
+static char *CleanName( const char *, const char *, int * );
+static int GetObjSize( AstObject *, int * );
+static const char *GetAttrib( AstObject *, const char *, int * );
+static const char *GetIntraFlag( AstIntraMap *, int * );
+static int MapMerge( AstMapping *, int, int, int *, AstMapping ***, int **, int * );
+static int TestAttrib( AstObject *, const char *, int * );
+static int TestIntraFlag( AstIntraMap *, int * );
+static void ClearAttrib( AstObject *, const char *, int * );
+static void ClearIntraFlag( AstIntraMap *, int * );
+static void Copy( const AstObject *, AstObject *, int * );
+static void Delete( AstObject *, int * );
+static void Dump( AstObject *, AstChannel *, int * );
+static int Equal( AstObject *, AstObject *, int * );
+static void IntraReg( const char *, int, int, void (*)( AstMapping *, int, int, const double *[], int, int, double *[] ), void (*)( void (*)( AstMapping *, int, int, const double *[], int, int, double *[] ), AstMapping *, int, int, const double *[], int, int, double *[], int * ), unsigned int, const char *, const char *, const char *, int * );
+static void SetAttrib( AstObject *, const char *, int * );
+static void SetIntraFlag( AstIntraMap *, const char *, int * );
+static void TranWrap( void (*)( AstMapping *, int, int, const double *[], int, int, double *[] ), AstMapping *, int, int, const double *[], int, int, double *[], int * );
+
+/* Member functions. */
+/* ================= */
+static char *CleanName( const char *name, const char *caller, int *status ) {
+/*
+*  Name:
+*     CleanName
+
+*  Purpose:
+*     Clean (and validate) a transformation function name.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     char *CleanName( const char *name, const char *caller, int *status )
+
+*  Class Membership:
+*     IntraMap member function.
+
+*  Description:
+*     This function cleans a transformation function name by removing
+*     all white space. It returns a copy of the cleaned name held in
+*     dynamically allocated memory. If the name is entirely blank, an
+*     error is reported.
+
+*  Parameters:
+*     name
+*        Pointer to a null-terminated string containing the name to be
+*        cleaned.
+*     caller
+*        Pointer to a null-terminated string containing the name of
+*        the calling function. This is only used to construct error
+*        messages.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     Pointer to a dynamically-allocated null-terminated string
+*     containing the cleaned name. A NULL pointer is returned if the
+*     name was entirely blank.
+
+*  Notes:
+*     - The memory holding the returned string should be deallocated
+*     (using astFree) when no longer required.
+*     - 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: */
+   char *result;                 /* Pointer to result string */
+   int i;                        /* Loop counter for input characters */
+   int len;                      /* Length of name */
+
+/* Initialise. */
+   result = NULL;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Determine the number of non-blank characters in the name supplied. */
+   len = 0;
+   for ( i = 0; name[ i ]; i++ ) if ( !isspace( (int) name[ i ] ) ) len++;
+
+/* If the name is entirely blank, then report an error. */
+   if ( !len ) {
+      astError( AST__ITFNI, "%s: Invalid blank transformation function name "
+                            "given.", status, caller );
+
+/* Otherwise, allocate memory to hold the cleaned name. */
+   } else {
+      result = astMalloc( (size_t) ( len + 1 ) );
+
+/* If OK, make a copy of the name with white space removed. */
+      if ( astOK ) {
+         len = 0;
+         for ( i = 0; name[ i ]; i++ ) {
+            if ( !isspace( (int) name[ i ] ) ) result[ len++ ] = name[ i ];
+         }
+
+/* Terminate the result string. */
+         result[ len ] = '\0';
+      }
+   }
+
+/* Return the result pointer. */
+   return result;
+}
+
+static void ClearAttrib( AstObject *this_object, const char *attrib, int *status ) {
+/*
+*  Name:
+*     ClearAttrib
+
+*  Purpose:
+*     Clear an attribute value for an IntraMap.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     void ClearAttrib( AstObject *this, const char *attrib, int *status )
+
+*  Class Membership:
+*     IntraMap member function (over-rides the astClearAttrib protected
+*     method inherited from the Mapping class).
+
+*  Description:
+*     This function clears the value of a specified attribute for an
+*     IntraMap, so that the default value will subsequently be used.
+
+*  Parameters:
+*     this
+*        Pointer to the IntraMap.
+*     attrib
+*        Pointer to a null terminated string specifying the attribute
+*        name.  This should be in lower case with no surrounding white
+*        space.
+*     status
+*        Pointer to the inherited status variable.
+*/
+
+/* Local Variables: */
+   AstIntraMap *this;            /* Pointer to the IntraMap structure */
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Obtain a pointer to the IntraMap structure. */
+   this = (AstIntraMap *) this_object;
+
+/* Check the attribute name and clear the appropriate attribute. */
+
+/* IntraFlag. */
+/* ---------- */
+   if ( !strcmp( attrib, "intraflag" ) ) {
+      astClearIntraFlag( this );
+
+/* Not recognised. */
+/* --------------- */
+/* If the attribute is not recognised, pass it on to the parent method
+   for further interpretation. */
+   } else {
+      (*parent_clearattrib)( this_object, attrib, status );
+   }
+}
+
+static int Equal( AstObject *this_object, AstObject *that_object, int *status ) {
+/*
+*  Name:
+*     Equal
+
+*  Purpose:
+*     Test if two IntraMaps are equivalent.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     int Equal( AstObject *this, AstObject *that, int *status )
+
+*  Class Membership:
+*     IntraMap 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 IntraMaps are equivalent.
+
+*  Parameters:
+*     this
+*        Pointer to the first Object (a IntraMap).
+*     that
+*        Pointer to the second Object.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     One if the IntraMaps 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: */
+   AstIntraMap *that;
+   AstIntraMap *this;
+   int nin;
+   int nout;
+   int result;
+
+/* Initialise. */
+   result = 0;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Obtain pointers to the two IntraMap structures. */
+   this = (AstIntraMap *) this_object;
+   that = (AstIntraMap *) that_object;
+
+/* Check the second object is a IntraMap. We know the first is a
+   IntraMap since we have arrived at this implementation of the virtual
+   function. */
+   if( astIsAIntraMap( that ) ) {
+
+/* Get the number of inputs and outputs and check they are the same for both. */
+      nin = astGetNin( this );
+      nout = astGetNout( this );
+      if( astGetNin( that ) == nin && astGetNout( that ) == nout ) {
+
+/* If the Invert flags for the two IntraMaps differ, it may still be possible
+   for them to be equivalent. First compare the IntraMaps if their Invert
+   flags are the same. In this case all the attributes of the two IntraMaps
+   must be identical. */
+         if( astGetInvert( this ) == astGetInvert( that ) ) {
+
+            if( this->ifun == that->ifun &&
+                this->intraflag && that->intraflag &&
+                !strcmp( this->intraflag, that->intraflag ) ) {
+               result = 1;
+            }
+
+/* If the Invert flags for the two IntraMaps differ, the attributes of the two
+   IntraMaps must be inversely related to each other. */
+         } else {
+
+/* In the specific case of a IntraMap, Invert flags must be equal. */
+            result = 0;
+
+         }
+      }
+   }
+
+/* If an error occurred, clear the result value. */
+   if ( !astOK ) result = 0;
+
+/* Return the result, */
+   return result;
+}
+
+static int GetObjSize( AstObject *this_object, int *status ) {
+/*
+*  Name:
+*     GetObjSize
+
+*  Purpose:
+*     Return the in-memory size of an Object.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     int GetObjSize( AstObject *this, int *status )
+
+*  Class Membership:
+*     IntraMap member function (over-rides the astGetObjSize protected
+*     method inherited from the parent class).
+
+*  Description:
+*     This function returns the in-memory size of the supplied IntraMap,
+*     in bytes.
+
+*  Parameters:
+*     this
+*        Pointer to the IntraMap.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     The Object size, in bytes.
+
+*  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: */
+   AstIntraMap *this;         /* Pointer to IntraMap structure */
+   int result;                /* Result value to return */
+
+/* Initialise. */
+   result = 0;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Obtain a pointers to the IntraMap structure. */
+   this = (AstIntraMap *) this_object;
+
+/* Invoke the GetObjSize method inherited from the parent class, and then
+   add on any components of the class structure defined by thsi class
+   which are stored in dynamically allocated memory. */
+   result = (*parent_getobjsize)( this_object, status );
+   result += astTSizeOf( this->intraflag );
+
+/* If an error occurred, clear the result value. */
+   if ( !astOK ) result = 0;
+
+/* Return the result, */
+   return result;
+}
+
+static const char *GetAttrib( AstObject *this_object, const char *attrib, int *status ) {
+/*
+*  Name:
+*     GetAttrib
+
+*  Purpose:
+*     Get the value of a specified attribute for an IntraMap.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     const char *GetAttrib( AstObject *this, const char *attrib, int *status )
+
+*  Class Membership:
+*     IntraMap member function (over-rides the protected astGetAttrib
+*     method inherited from the Mapping class).
+
+*  Description:
+*     This function returns a pointer to the value of a specified
+*     attribute for a IntraMap, formatted as a character string.
+
+*  Parameters:
+*     this
+*        Pointer to the IntraMap.
+*     attrib
+*        Pointer to a null-terminated string containing the name of
+*        the attribute whose value is required. This name should be in
+*        lower case, with all white space removed.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     - Pointer to a null-terminated string containing the attribute
+*     value.
+
+*  Notes:
+*     - The returned string pointer may point at memory allocated
+*     within the IntraMap, or at static memory. The contents of the
+*     string may be over-written or the pointer may become invalid
+*     following a further invocation of the same function or any
+*     modification of the IntraMap. A copy of the string should
+*     therefore be made if necessary.
+*     - 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: */
+   AstIntraMap *this;            /* Pointer to the IntraMap structure */
+   const char *result;           /* Pointer value to return */
+
+/* Initialise. */
+   result = NULL;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Obtain a pointer to the IntraMap structure. */
+   this = (AstIntraMap *) this_object;
+
+/* Compare "attrib" with each recognised attribute name in turn,
+   obtaining the value of the required attribute. If necessary, write
+   the value into "buff" as a null-terminated string in an appropriate
+   format.  Set "result" to point at the result string. */
+
+/* IntraFlag. */
+/* ---------- */
+   if ( !strcmp( attrib, "intraflag" ) ) {
+      result = astGetIntraFlag( this );
+
+/* Not recognised. */
+/* --------------- */
+/* If the attribute name was not recognised, pass it on to the parent
+   method for further interpretation. */
+   } else {
+      result = (*parent_getattrib)( this_object, attrib, status );
+   }
+
+/* Return the result. */
+   return result;
+}
+
+void astInitIntraMapVtab_(  AstIntraMapVtab *vtab, const char *name, int *status ) {
+/*
+*+
+*  Name:
+*     astInitIntraMapVtab
+
+*  Purpose:
+*     Initialise a virtual function table for an IntraMap.
+
+*  Type:
+*     Protected function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     void astInitIntraMapVtab( AstIntraMapVtab *vtab, const char *name )
+
+*  Class Membership:
+*     IntraMap vtab initialiser.
+
+*  Description:
+*     This function initialises the component of a virtual function
+*     table which is used by the IntraMap 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 global 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 astIsAIntraMap) 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->ClearIntraFlag = ClearIntraFlag;
+   vtab->GetIntraFlag = GetIntraFlag;
+   vtab->SetIntraFlag = SetIntraFlag;
+   vtab->TestIntraFlag = TestIntraFlag;
+
+/* 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_getobjsize = object->GetObjSize;
+   object->GetObjSize = GetObjSize;
+
+   parent_clearattrib = object->ClearAttrib;
+   object->ClearAttrib = ClearAttrib;
+   parent_getattrib = object->GetAttrib;
+   object->GetAttrib = GetAttrib;
+   parent_setattrib = object->SetAttrib;
+   object->SetAttrib = SetAttrib;
+   parent_testattrib = object->TestAttrib;
+   object->TestAttrib = TestAttrib;
+
+   parent_transform = mapping->Transform;
+   mapping->Transform = Transform;
+
+/* Store replacement pointers for methods which will be over-ridden by
+   new member functions implemented here. */
+   object->Equal = Equal;
+   mapping->MapMerge = MapMerge;
+
+/* Store pointers to inherited methods that will be invoked explicitly
+   by this class. */
+   parent_getnin = mapping->GetNin;
+   parent_getnout = mapping->GetNout;
+
+/* Declare the copy constructor, destructor and class dump
+   function. */
+   astSetCopy( vtab, Copy );
+   astSetDelete( vtab, Delete );
+   astSetDump( vtab, Dump, "IntraMap",
+               "Map points using a private transformation function" );
+
+/* 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 void IntraReg( const char *name, int nin, int nout,
+                      void (* tran)( AstMapping *, int, int, const double *[],
+                                     int, int, double *[] ),
+                      void (* tran_wrap)( void (*)( AstMapping *, int, int,
+                                                    const double *[], int, int,
+                                                    double *[] ),
+                                          AstMapping *, int, int,
+                                          const double *[], int, int,
+                                          double *[], int * ),
+                      unsigned int flags,
+                      const char *purpose, const char *author,
+                      const char *contact, int *status ) {
+/*
+*  Name:
+*     IntraReg
+
+*  Purpose:
+*     Register a transformation function for use by an IntraMap.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     void IntraReg( const char *name, int nin, int nout,
+*                    void (* tran)( AstMapping *, int, int, const double *[],
+*                                   int, int, double *[] ),
+*                    void (* tran_wrap)( void (*)( AstMapping *, int, int,
+*                                                  const double *[], int, int,
+*                                                  double *[] ),
+*                                        AstMapping *, int, int,
+*                                        const double *[], int, int,
+*                                        double *[], int * ),
+*                    unsigned int flags,
+*                    const char *purpose, const char *author,
+*                    const char *contact, int *status )
+
+*  Class Membership:
+*     IntraMap member function.
+
+*  Description:
+*     This function registers a transformation function which will
+*     later be used by an IntraMap and associates it with a name. It
+*     also stores related information which will be required by the
+*     IntraMap.
+
+*  Parameters:
+*     name
+*        Pointer to a null-terminated string containing the name to be
+*        used to identify the transformation function. This string is
+*        case sensitive. All white space is removed before use.
+*     nin
+*        The number of input coordinates per point (or AST__ANY if any
+*        number are allowed).
+*     nout
+*        The number of output coordinates per point (or AST__ANY if
+*        any number are allowed).
+*     tran
+*        Pointer to the transformation function to be registered.
+*        This may have any form of interface, which need not be known
+*        to the implementation of the IntraMap class. Instead, the
+*        method of invoking the transformation function should be
+*        encapsulated in the "tran_wrap" function (below).
+*     tran_wrap
+*        Pointer to a wrapper function appropriate to the transformation
+*        function (above). This wrapper function should have the same
+*        interface as astTranP (from the Mapping class), except that it takes
+*        a pointer to a function like "tran" as an additional first argument.
+*        The purpose of this wrapper is to invoke the transformation function
+*        via the pointer supplied, to pass it the necessary information
+*        derived from the remainder of its arguments, and then to return the
+*        results.
+*     flags
+*        This argument may be used to supply a set of flags which
+*        control the behaviour of any IntraMap which uses the
+*        registered transformation function. See the public interface
+*        for astIntraReg for details.
+*     purpose
+*        Pointer to a null-terminated string containing a short (one
+*        line) textual comment to describe the purpose of the
+*        transformation function.
+*     author
+*        Pointer to a null-terminated string containing the name of
+*        the author of the transformation function.
+*     contact
+*        Pointer to a null-terminated string containing contact
+*        details for the author of the function (e.g. an e-mail or WWW
+*        address).
+*     status
+*        Pointer to the inherited status variable.
+*/
+
+/* Local Variables: */
+   astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
+   char *clname;                 /* Pointer to cleaned name string */
+   int found;                    /* Transformation function found? */
+   int ifun;                     /* Loop counter for function information */
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* This function modifies the global static tran_data array, so we use a
+   mutex to ensure that only one thread can run this function at any one
+   time. */
+   LOCK_MUTEX1;
+
+/* Get a pointer to the thread specific global data structure. */
+   astGET_GLOBALS(NULL);
+
+/* Indicate that subsequent memory allocations may never be freed (other
+   than by any AST exit handler). */
+   astBeginPM;
+
+/* Clean (and validate) the name supplied. */
+   clname = CleanName( name, "astIntraReg", status );
+
+/* If OK, also validate the numbers of input and output
+   coordinates. Report an error if necessary. */
+   if ( astOK ) {
+      if ( ( nin < 0 ) && ( nin != AST__ANY ) ) {
+         astError( AST__BADNI, "astIntraReg(%s): Bad number of input "
+                               "coordinates (%d).", status, clname, nin );
+         astError( AST__BADNI, "This number should be zero or more (or "
+                               "AST__ANY)." , status);
+
+      } else if ( ( nout < 0 ) && ( nout != AST__ANY ) ) {
+         astError( AST__BADNO, "astIntraReg(%s): Bad number of output "
+                               "coordinates (%d).", status, clname, nout );
+         astError( AST__BADNO, "This number should be zero or more (or "
+                               "AST__ANY)." , status);
+      }
+   }
+
+/* Search the array of transformation function data to see if a
+   function with the same name has already been registered. */
+   if ( astOK ) {
+      found = 0;
+      for ( ifun = 0; ifun < tran_nfun; ifun++ ) {
+         if ( ( found = !strcmp( clname, tran_data[ ifun ].name ) ) ) break;
+      }
+
+/* If so, then check that the information supplied this time is
+   identical to that supplied before. If any discrepancy is found,
+   report an error. */
+      if ( found ) {
+         if ( ( nin != tran_data[ ifun ].nin ) ||
+              ( nout != tran_data[ ifun ].nout ) ||
+              ( tran != tran_data[ ifun ].tran ) ||
+              ( tran_wrap != tran_data[ ifun ].tran_wrap ) ||
+              ( flags != tran_data[ ifun ].flags ) ||
+              strcmp( purpose, tran_data[ ifun ].purpose ) ||
+              strcmp( author, tran_data[ ifun ].author ) ||
+              strcmp( contact, tran_data[ ifun ].contact ) ) {
+            astError( AST__MRITF, "astIntraReg: Invalid attempt to register "
+                                  "the transformation function name \"%s\" "
+                                  "multiple times.", status, clname );
+         }
+
+/* If this is a new function, extend the array of transformation
+   function data to accommodate it. */
+      } else {
+
+         tran_data = astGrow( tran_data, tran_nfun + 1, sizeof( AstIntraMapTranData ) );
+
+/* Store the information supplied. */
+         if ( astOK ) {
+            tran_data[ tran_nfun ].name = clname;
+            tran_data[ tran_nfun ].nin = nin;
+            tran_data[ tran_nfun ].nout = nout;
+            tran_data[ tran_nfun ].tran = tran;
+            tran_data[ tran_nfun ].tran_wrap = tran_wrap;
+            tran_data[ tran_nfun ].flags = flags;
+            tran_data[ tran_nfun ].purpose =
+               astStore( NULL, purpose, strlen( purpose ) + (size_t) 1 );
+            tran_data[ tran_nfun ].author =
+               astStore( NULL, author, strlen( author ) + (size_t) 1 );
+            tran_data[ tran_nfun ].contact =
+               astStore( NULL, contact, strlen( contact ) + (size_t) 1 );
+
+/* If successful, increment the count of transformation functions
+   registered. */
+            if ( astOK ) {
+               tran_nfun++;
+
+/* If an error occurred, free any memory that was allocated. */
+            } else {
+               tran_data[ tran_nfun ].name = NULL;
+               tran_data[ tran_nfun ].purpose =
+                  astFree( tran_data[ tran_nfun ].purpose );
+               tran_data[ tran_nfun ].author =
+                  astFree( tran_data[ tran_nfun ].author );
+               tran_data[ tran_nfun ].contact =
+                  astFree( tran_data[ tran_nfun ].contact );
+            }
+         }
+      }
+   }
+
+/* If an error occurred, free the memory holding the cleaned function
+   name. */
+   if ( !astOK ) clname = astFree( clname );
+
+/* Mark the end of the section in which memory allocations may never be
+   freed (other than by any AST exit handler). */
+   astEndPM;
+
+/* Unlock the mutex that ensures that only one thread can run this function
+   at any one time. */
+   UNLOCK_MUTEX1;
+
+}
+
+void astIntraReg_( const char *name, int nin, int nout,
+                   void (* tran)( AstMapping *, int, int, const double *[],
+                                  int, int, double *[] ),
+                   unsigned int flags, const char *purpose, const char *author,
+                   const char *contact, int *status ) {
+/*
+*++
+*  Name:
+c     astIntraReg
+f     AST_INTRAREG
+
+*  Purpose:
+c     Register a transformation function for use by an IntraMap.
+f     Register a transformation routine for use by an IntraMap.
+
+*  Type:
+*     Public function.
+
+*  Synopsis:
+c     #include "intramap.h"
+c     astIntraReg( const char *name, int nin, int nout,
+c                  void (* tran)( AstMapping *, int, int, const double *[],
+c                                 int, int, double *[] ),
+c                  unsigned int flags, const char *purpose, const char *author,
+c                  const char *contact )
+f     CALL AST_INTRAREG( NAME, NIN, NOUT, TRAN, FLAGS, PURPOSE, AUTHOR,
+f                        CONTACT, STATUS )
+
+*  Class Membership:
+*     IntraMap member function.
+
+*  Description:
+c     This function registers a privately-defined coordinate
+c     transformation function written in C so that it may be used to
+c     create an IntraMap. An IntraMap is a specialised form of Mapping
+c     which encapsulates the C function so that it may be used like
+c     any other AST Mapping. This allows you to create Mappings that
+c     perform any conceivable coordinate transformation.
+f     This function registers a privately-defined coordinate
+f     transformation routine written in Fortran so that it may be used
+f     to create an IntraMap. An IntraMap is a specialised form of
+f     Mapping which encapsulates the Fortran routine so that it may be
+f     used like any other AST Mapping. This allows you to create
+f     Mappings that perform any conceivable coordinate transformation.
+*
+c     Registration of relevant transformation functions is required
+c     before using the astIntraMap constructor function to create an
+c     IntraMap or reading an external representation of an IntraMap
+c     from a Channel.
+f     Registration of relevant transformation routines is required
+f     before using the AST_INTRAMAP constructor function to create an
+f     IntraMap or reading an external representation of an IntraMap
+f     from a Channel.
+
+*  Parameters:
+c     name
+f     NAME = CHARACTER * ( * ) (Given)
+c        Pointer to a null-terminated string containing a unique name
+c        to be associated with the transformation function in order to
+c        identify it. This name is case sensitive. All white space
+c        will be removed before use.
+f        A character string containing a unique name to be associated
+f        with the transformation routine in order to identify it. This
+f        name is case sensitive. All white space will be removed
+f        before use.
+c     nin
+f     NIN = INTEGER (Given)
+c        The number of input coordinates accepted by the
+c        transformation function (i.e. the number of dimensions of the
+c        space in which the input points reside). A value of AST__ANY
+c        may be given if the function is able to accommodate a
+c        variable number of input coordinates.
+f        The number of input coordinates accepted by the
+f        transformation routine (i.e. the number of dimensions of the
+f        space in which the input points reside). A value of AST__ANY
+f        may be given if the routine is able to accommodate a variable
+f        number of input coordinates.
+c     nout
+f     NOUT = INTEGER (Given)
+c        The number of output coordinates produced by the
+c        transformation function (i.e. the number of dimensions of the
+c        space in which the output points reside). A value of AST__ANY
+c        may be given if the function is able to produce a variable
+c        number of output coordinates.
+f        The number of output coordinates produced by the
+f        transformation routine (i.e. the number of dimensions of the
+f        space in which the output points reside). A value of AST__ANY
+f        may be given if the routine is able to produce a variable
+f        number of output coordinates.
+c     tran
+f     TRAN = SUBROUTINE (Given)
+c        Pointer to the transformation function to be registered.
+c        This function should perform whatever coordinate
+c        transformations are required and should have an interface
+c        like astTranP (q.v.).
+f        The transformation routine to be registered.  This routine
+f        should perform whatever coordinate transformations are
+f        required and should have an interface like AST_TRANN (q.v.).
+f
+f        This transformation routine must also appear in an EXTERNAL
+f        statement in the routine which calls AST_INTRAREG.
+c     flags
+f     FLAGS = INTEGER (Given)
+c        This value may be used to supply a set of flags which
+c        describe the transformation function and which may affect the
+c        behaviour of any IntraMap which uses it.  Often, a value of
+c        zero will be given here, but you may also supply the bitwise
+c        OR of a set of flags as described in the "Transformation
+c        Flags" section (below).
+f        This value may be used to supply a set of flags which
+f        describe the transformation routine and which may affect the
+f        behaviour of any IntraMap which uses it.  Often, a value of
+f        zero will be given here, but you may also supply the sum of a
+f        set of flags as described in the "Transformation Flags"
+f        section (below).
+c     purpose
+f     PURPOSE = CHARACTER * ( * ) (Given)
+c        Pointer to a null-terminated string containing a short (one
+c        line) textual comment to describe the purpose of the
+c        transformation function.
+f        A character string containing a short (one line) textual
+f        comment to describe the purpose of the transformation
+f        routine.
+c     author
+f     AUTHOR = CHARACTER * ( * ) (Given)
+c        Pointer to a null-terminated string containing the name of
+c        the author of the transformation function.
+f        A character string containing the name of the author of the
+f        transformation routine.
+c     contact
+f     CONTACT = CHARACTER * ( * ) (Given)
+c        Pointer to a null-terminated string containing contact
+c        details for the author of the transformation function
+c        (e.g. an e-mail or WWW address). If any IntraMap which uses
+c        this transformation function is exported as part of a dataset
+c        to an external user who does not have access to the function,
+c        then these contact details should allow them to obtain the
+c        necessary code.
+f        A character string containing contact details for the author
+f        of the transformation routine (e.g. an e-mail or WWW
+f        address). If any IntraMap which uses this transformation
+f        routine is exported as part of a dataset to an external user
+f        who does not have access to the routine, then these contact
+f        details should allow them to obtain the necessary code.
+f     STATUS = INTEGER (Given and Returned)
+f        The global status.
+
+*  Notes:
+c     - Beware that an external representation of an IntraMap (created
+c     by writing it to a Channel) will not include the coordinate
+c     transformation function which it uses, so will only refer to the
+c     function by its name (as assigned using astIntraReg).
+c     Consequently, the external representation cannot be utilised by
+c     another program unless that program has also registered the same
+c     transformation function with the same name using an identical
+c     invocation of astIntraReg. If no such registration has been
+c     performed, then attempting to read the external representation
+c     will result in an error.
+f     - Beware that an external representation of an IntraMap (created
+f     by writing it to a Channel) will not include the coordinate
+f     transformation routine which it uses, so will only refer to the
+f     routine by its name (as assigned using AST_INTRAREG).
+f     Consequently, the external representation cannot be utilised by
+f     another program unless that program has also registered the same
+f     transformation routine with the same name using an identical
+f     invocation of AST_INTRAREG. If no such registration has been
+f     performed, then attempting to read the external representation
+f     will result in an error.
+c     - You may use astIntraReg to register a transformation function
+c     with the same name more than once, but only if the arguments
+c     supplied are identical on each occasion (i.e there is no way of
+c     changing things once a function has been successfully registered
+c     under a given name, and attempting to do so will result in an
+c     error). This feature simply allows registration to be performed
+c     independently, but consistently, at several places within your
+c     program, without having to check whether it has already been
+c     done.
+f     - You may use AST_INTRAREG to register a transformation routine
+f     with the same name more than once, but only if the arguments
+f     supplied are identical on each occasion (i.e there is no way of
+f     changing things once a routine has been successfully registered
+f     under a given name, and attempting to do so will result in an
+f     error). This feature simply allows registration to be performed
+f     independently, but consistently, at several places within your
+f     program, without having to check whether it has already been
+f     done.
+c     - If an error occurs in the transformation function, this may be
+c     indicated by setting the AST error status to an error value
+c     (using astSetStatus) before it returns.  This will immediately
+c     terminate the current AST operation.  The error value AST__ITFER
+c     is available for this purpose, but other values may also be used
+c     (e.g. if you wish to distinguish different types of error).
+f     - If an error occurs in the transformation routine, this may be
+f     indicated by setting its STATUS argument to an error value
+f     before it returns.  This will immediately terminate the current
+f     AST operation.  The error value AST__ITFER is available for this
+f     purpose, but other values may also be used (e.g. if you wish to
+f     distinguish different types of error). The AST__ITFER error
+f     value is defined in the AST_ERR include file.
+
+*  Transformation Flags:
+c     The following flags are defined in the ``ast.h'' header file and
+c     allow you to provide further information about the nature of the
+c     transformation function. Having selected the set of flags which
+c     apply, you should supply the bitwise OR of their values as the
+c     ``flags'' argument to astIntraReg.
+f     The following flags are defined in the AST_PAR include file and
+f     allow you to provide further information about the nature of the
+f     transformation routine. Having selected the set of flags which
+f     apply, you should supply the sum of their values as the FLAGS
+f     argument to AST_INTRAREG.
+
+c     - AST__NOFWD: If this flag is set, it indicates that the
+c     transformation function does not implement a forward coordinate
+c     transformation. In this case, any IntraMap which uses it will
+c     have a TranForward attribute value of zero and the
+c     transformation function itself will not be invoked with its
+c     ``forward'' argument set to a non-zero value.  By default, it is
+c     assumed that a forward transformation is provided.
+f     - AST__NOFWD: If this flag is set, it indicates that the
+f     transformation routine does not implement a forward coordinate
+f     transformation. In this case, any IntraMap which uses it will
+f     have a TranForward attribute value of zero and the
+f     transformation routine itself will not be called with its
+f     FORWARD argument set to .TRUE.. By default, it is assumed that a
+f     forward transformation is provided.
+c     - AST__NOINV: If this flag is set, it indicates that the
+c     transformation function does not implement an inverse coordinate
+c     transformation. In this case, any IntraMap which uses it will
+c     have a TranInverse attribute value of zero and the
+c     transformation function itself will not be invoked with its
+c     ``forward'' argument set to zero.  By default, it is assumed
+c     that an inverse transformation is provided.
+f     - AST__NOINV: If this flag is set, it indicates that the
+f     transformation routine does not implement an inverse coordinate
+f     transformation. In this case, any IntraMap which uses it will
+f     have a TranInverse attribute value of zero and the
+f     transformation routine itself will not be called with its
+f     FORWARD argument set to .FALSE.. By default, it is assumed that
+f     an inverse transformation is provided.
+c     - AST__SIMPFI: You may set this flag if applying the
+c     transformation function's forward coordinate transformation,
+c     followed immediately by the matching inverse transformation,
+c     should always restore the original set of coordinates. It
+c     indicates that AST may replace such a sequence of operations by
+c     an identity Mapping (a UnitMap) if it is encountered while
+c     simplifying a compound Mapping (e.g. using astSimplify).  It is
+c     not necessary that both transformations have actually been
+c     implemented.
+f     - AST__SIMPFI: You may set this flag if applying the
+f     transformation routine's forward coordinate transformation,
+f     followed immediately by the matching inverse transformation,
+f     should always restore the original set of coordinates. It
+f     indicates that AST may replace such a sequence of operations by
+f     an identity Mapping (a UnitMap) if it is encountered while
+f     simplifying a compound Mapping (e.g. using AST_SIMPLIFY).  It is
+f     not necessary that both transformations have actually been
+f     implemented.
+c     - AST__SIMPIF: You may set this flag if applying the
+c     transformation function's inverse coordinate transformation,
+c     followed immediately by the matching forward transformation,
+c     should always restore the original set of coordinates. It
+c     indicates that AST may replace such a sequence of operations by
+c     an identity Mapping (a UnitMap) if it is encountered while
+c     simplifying a compound Mapping (e.g. using astSimplify).  It is
+c     not necessary that both transformations have actually been
+c     implemented.
+f     - AST__SIMPIF: You may set this flag if applying the
+f     transformation routine's inverse coordinate transformation,
+f     followed immediately by the matching forward transformation,
+f     should always restore the original set of coordinates. It
+f     indicates that AST may replace such a sequence of operations by
+f     an identity Mapping (a UnitMap) if it is encountered while
+f     simplifying a compound Mapping (e.g. using AST_SIMPLIFY).  It is
+f     not necessary that both transformations have actually been
+f     implemented.
+*--
+*/
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Register the transformation function together with the appropriate
+   wrapper function for the C language. */
+   IntraReg( name, nin, nout, tran, TranWrap, flags, purpose, author,
+             contact, status );
+}
+
+void astIntraRegFor_( const char *name, int nin, int nout,
+                      void (* tran)( AstMapping *, int, int, const double *[],
+                                     int, int, double *[] ),
+                      void (* tran_wrap)( void (*)( AstMapping *, int, int,
+                                                    const double *[], int, int,
+                                                    double *[] ),
+                                          AstMapping *, int, int,
+                                          const double *[], int, int,
+                                          double *[], int * ),
+                      unsigned int flags, const char *purpose,
+                      const char *author, const char *contact, int *status ) {
+/*
+*+
+*  Name:
+*     astIntraRegFor
+
+*  Purpose:
+*     Register a foreign language transformation function for an IntraMap.
+
+*  Type:
+*     Public function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     void astIntraRegFor( const char *name, int nin, int nout,
+*                          void (* tran)( AstMapping *, int, int,
+*                                         const double *[], int, int,
+*                                         double *[] ),
+*                          void (* tran_wrap)( void (*)( AstMapping *, int,
+*                                                        int, const double *[],
+*                                                        int, int,
+*                                                        double *[] ),
+*                                              AstMapping *, int, int,
+*                                              const double *[], int, int,
+*                                              double *[], int * ),
+*                          unsigned int flags, const char *purpose,
+*                          const char *author, const char *contact )
+
+*  Class Membership:
+*     IntraMap member function.
+
+*  Description:
+*     This function registers a transformation function provided by a
+*     foreign language interface which will later be used by an
+*     IntraMap, and associates it with a name. It also stores related
+*     information which will be required by the IntraMap.
+
+*  Parameters:
+*     name
+*        Pointer to a null-terminated string containing the name to be
+*        used to identify the transformation function. This string is
+*        case sensitive. All white space is removed before use.
+*     nin
+*        The number of input coordinates per point (or AST__ANY if any
+*        number are allowed).
+*     nout
+*        The number of output coordinates per point (or AST__ANY if
+*        any number are allowed).
+*     tran
+*        Pointer to the foreign language transformation function to be
+*        registered. This may have any form of interface, which need
+*        not be known to the implementation of the IntraMap
+*        class. Instead, the method of invoking the transformation
+*        function should be encapsulated in the "tran_wrap" function
+*        (below).
+*     tran_wrap
+*        Pointer to a wrapper function appropriate to the foreign
+*        language interface. This wrapper function should have the
+*        same interface as astTranP (from the Mapping class), except
+*        that it takes a pointer to a function like "tran" as an additional
+*        first argument. The purpose of this wrapper is to invoke the
+*        transformation function via the pointer supplied, to pass it the
+*        necessary information derived from the remainder of its arguments,
+*        and then to return the results.
+*     flags
+*        This argument may be used to supply a set of flags which
+*        control the behaviour of any IntraMap which uses the
+*        registered transformation function. See the description of
+*        astIntraReg for details.
+*     purpose
+*        Pointer to a null-terminated string containing a short (one
+*        line) textual comment to describe the purpose of the
+*        transformation function.
+*     author
+*        Pointer to a null-terminated string containing the name of
+*        the author of the transformation function.
+*     contact
+*        Pointer to a null-terminated string containing contact
+*        details for the author of the transformation function
+*        (e.g. an e-mail address or URL). If any IntraMap using this
+*        transformation function is exported as part of a dataset to
+*        an external user who does not have access to the function,
+*        then these contact details should allow them to obtain the
+*        necessary code.
+
+*  Notes:
+*     - This function is only available through the public interface
+*     to the IntraMap class (not the protected interface) and is
+*     intended solely for use in implementing foreign language
+*     interfaces to this class.
+*-
+*/
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Register the transformation function together with the appropriate
+   wrapper function for the foreign language interface. */
+   IntraReg( name, nin, nout, tran, tran_wrap, flags, purpose, author,
+             contact, status );
+}
+
+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 an IntraMap.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     int MapMerge( AstMapping *this, int where, int series, int *nmap,
+*                   AstMapping ***map_list, int **invert_list, int *status )
+
+*  Class Membership:
+*     IntraMap 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 IntraMap 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 IntraMap 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 IntraMap which is to be merged with
+*        its neighbours. This should be a cloned copy of the IntraMap
+*        pointer contained in the array element "(*map_list)[where]"
+*        (see below). This pointer will not be annulled, and the
+*        IntraMap it identifies will not be modified by this function.
+*     where
+*        Index in the "*map_list" array (below) at which the pointer
+*        to the nominated IntraMap 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: */
+   astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
+   AstIntraMap *intramap1;       /* Pointer to first IntraMap */
+   AstIntraMap *intramap2;       /* Pointer to second IntraMap */
+   AstMapping *new;              /* Pointer to replacement Mapping */
+   const char *class;            /* Pointer to Mapping class string */
+   int imap1;                    /* Index of first IntraMap */
+   int imap2;                    /* Index of second IntraMap */
+   int imap;                     /* Loop counter for Mappings */
+   int invert1;                  /* Invert flag value (1st IntraMap) */
+   int invert2;                  /* Invert flag value (2nd IntraMap) */
+   int nin1;                     /* No. input coordinates (1st IntraMap) */
+   int nout2;                    /* No. output coordinates (2nd IntraMap) */
+   int result;                   /* Result value to return */
+   int simpler;                  /* Mappings simplified? */
+
+/* Initialise the returned result. */
+   result = -1;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Get a pointer to the thread specific global data structure. */
+   astGET_GLOBALS(this);
+
+/* Further initialisation. */
+   new = NULL;
+   simpler = 0;
+   nin1 = -1;
+
+/* We will only handle the case of IntraMaps in series and will
+   consider merging the nominated IntraMap with the Mapping which
+   follows it. Check that there is such a Mapping. */
+   if ( series && ( ( where + 1 ) < *nmap ) ) {
+
+/* Obtain the indices of the two potential IntraMaps to be merged and
+   a pointer to the first one. */
+      imap1 = where;
+      imap2 = where + 1;
+      intramap1 = (AstIntraMap *) ( *map_list )[ imap1 ];
+
+/* Obtain the Class string of the second Mapping and determine if it
+   is an IntraMap. */
+      class = astGetClass( ( *map_list )[ imap2 ] );
+      if ( astOK && !strcmp( class, "IntraMap" ) ) {
+
+/* Obtain a pointer to the second IntraMap. */
+         intramap2 = (AstIntraMap *) ( *map_list )[ imap2 ];
+
+/* Check that the two IntraMaps use the same transformation function
+   and have the same IntraFlag string (if set). */
+         if ( ( intramap1->ifun == intramap2->ifun ) &&
+              !strcmp( intramap1->intraflag ? intramap1->intraflag : "",
+                       intramap2->intraflag ? intramap2->intraflag : "" ) ) {
+
+/* Determine the number of input coordinates that the first IntraMap
+   would have if its Invert attribute were set to the value of the
+   associated invert flag. Take account of the current Invert
+   attribute in obtaining this value. */
+            invert1 = ( *invert_list )[ imap1 ];
+            if ( astGetInvert( intramap1 ) ) {
+               nin1 = invert1 ? astGetNin( intramap1 ) :
+                                astGetNout( intramap1 );
+            } else {
+               nin1 = invert1 ? astGetNout( intramap1 ) :
+                                astGetNin( intramap1 );
+            }
+
+/* Similarly, determine the number of output coordinates that the
+   second IntraMap would have. */
+            invert2 = ( *invert_list )[ imap2 ];
+            if ( astGetInvert( intramap2 ) ) {
+               nout2 = invert2 ? astGetNout( intramap2 ) :
+                                 astGetNin( intramap2 );
+            } else {
+               nout2 = invert2 ? astGetNin( intramap2 ) :
+                                 astGetNout( intramap2 );
+            }
+
+/* Check that the effect of applying the two IntraMaps will be to
+   preserve the number of coordinates. */
+            if ( astOK && ( nin1 == nout2 ) ) {
+
+/* If so, check if the first transformation function is applied in the
+   forward direction and the second in the inverse direction. If so,
+   note if this configuration can be simplified. */
+               if ( !invert1 && invert2 ) {
+                  simpler = tran_data[ intramap1->ifun ].flags & AST__SIMPFI;
+
+/* Similarly, if the first transformation function is applied in the
+   inverse direction and the second in the forward direction, then
+   note if this configuration can be simplified. */
+               } else if ( invert1 && !invert2 ) {
+                  simpler = tran_data[ intramap1->ifun ].flags & AST__SIMPIF;
+               }
+            }
+         }
+      }
+
+/* If the two IntraMaps can be simplified, create a UnitMap to replace
+   them. */
+      if ( simpler ) {
+         new = (AstMapping *) astUnitMap( nin1, "", status );
+
+/* Annul the pointers to the IntraMaps. */
+         if ( astOK ) {
+            ( *map_list )[ imap1 ] = astAnnul( ( *map_list )[ imap1 ] );
+            ( *map_list )[ imap2 ] = astAnnul( ( *map_list )[ imap2 ] );
+
+/* Insert the pointer to the replacement Mapping and initialise its
+   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 - 1 ] = ( *map_list )[ imap ];
+               ( *invert_list )[ imap - 1 ] = ( *invert_list )[ imap ];
+            }
+
+/* Clear the vacated elements at the end. */
+            ( *map_list )[ *nmap - 1 ] = NULL;
+            ( *invert_list )[ *nmap - 1 ] = 0;
+
+/* Decrement the Mapping count and return the index of the first
+   modified element. */
+            ( *nmap )--;
+            result = imap1;
+         }
+      }
+   }
+
+/* If an error occurred, clear the returned result. */
+   if ( !astOK ) result = -1;
+
+/* Return the result. */
+   return result;
+}
+
+static void SetAttrib( AstObject *this_object, const char *setting, int *status ) {
+/*
+*  Name:
+*     SetAttrib
+
+*  Purpose:
+*     Set an attribute value for an IntraMap.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     void SetAttrib( AstObject *this, const char *setting, int *status )
+
+*  Class Membership:
+*     IntraMap member function (over-rides the astSetAttrib method inherited
+*     from the Mapping class).
+
+*  Description:
+*     This function assigns an attribute value for a IntraMap, the
+*     attribute and its value being specified by means of a string of
+*     the form:
+*
+*        "attribute= value "
+*
+*     Here, "attribute" specifies the attribute name and should be in
+*     lower case with no white space present. The value to the right
+*     of the "=" should be a suitable textual representation of the
+*     value to be assigned and this will be interpreted according to
+*     the attribute's data type.  White space surrounding the value is
+*     only significant for string attributes.
+
+*  Parameters:
+*     this
+*        Pointer to the IntraMap.
+*     setting
+*        Pointer to a null terminated string specifying the new attribute
+*        value.
+*     status
+*        Pointer to the inherited status variable.
+*/
+
+/* Local Vaiables: */
+   AstIntraMap *this;            /* Pointer to the IntraMap structure */
+   int intraflag;                /* Offset of IntraFlag value in string */
+   int len;                      /* Length of setting string */
+   int nc;                       /* Number of characters read by astSscanf */
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Obtain a pointer to the IntraMap structure. */
+   this = (AstIntraMap *) this_object;
+
+/* Obtain the length of the setting string. */
+   len = strlen( setting );
+
+/* Test for each recognised attribute in turn, using "astSscanf" to parse the
+   setting string and extract the attribute value (or an offset to it in the
+   case of string values). In each case, use the value set in "nc" to check
+   that the entire string was matched. Once a value has been obtained, use the
+   appropriate method to set it. */
+
+/* IntraFlag. */
+/* ---------- */
+   if ( nc = 0,
+        ( 0 == astSscanf( setting, "intraflag=%n%*[^\n]%n", &intraflag, &nc ) )
+        && ( nc >= len ) ) {
+      astSetIntraFlag( this, setting + intraflag );
+
+/* Not recognised. */
+/* --------------- */
+/* If the attribute is not recognised, pass it on to the parent method
+   for further interpretation. */
+   } else {
+      (*parent_setattrib)( this_object, setting, status );
+   }
+}
+
+static int TestAttrib( AstObject *this_object, const char *attrib, int *status ) {
+/*
+*  Name:
+*     TestAttrib
+
+*  Purpose:
+*     Test if a specified attribute value is set for an IntraMap.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     int TestAttrib( AstObject *this, const char *attrib, int *status )
+
+*  Class Membership:
+*     IntraMap member function (over-rides the astTestAttrib protected
+*     method inherited from the Mapping class).
+
+*  Description:
+*     This function returns a boolean result (0 or 1) to indicate whether
+*     a value has been set for one of a IntraMap's attributes.
+
+*  Parameters:
+*     this
+*        Pointer to the IntraMap.
+*     attrib
+*        Pointer to a null terminated string specifying the attribute
+*        name.  This should be in lower case with no surrounding white
+*        space.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     One if a value has been set, otherwise zero.
+
+*  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: */
+   AstIntraMap *this;            /* Pointer to the IntraMap structure */
+   int result;                   /* Result value to return */
+
+/* Initialise. */
+   result = 0;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Obtain a pointer to the IntraMap structure. */
+   this = (AstIntraMap *) this_object;
+
+/* Check the attribute name and test the appropriate attribute. */
+
+/* IntraFlag. */
+/* ---------- */
+   if ( !strcmp( attrib, "intraflag" ) ) {
+      result = astTestIntraFlag( this );
+
+/* Not recognised. */
+/* --------------- */
+/* If the attribute is not recognised, pass it on to the parent method
+   for further interpretation. */
+   } else {
+      result = (*parent_testattrib)( this_object, attrib, status );
+   }
+
+/* Return the result, */
+   return result;
+}
+
+static AstPointSet *Transform( AstMapping *this_mapping, AstPointSet *in,
+                               int forward, AstPointSet *out, int *status ) {
+/*
+*  Name:
+*     Transform
+
+*  Purpose:
+*     Apply an IntraMap to transform a set of points.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     AstPointSet *Transform( AstMapping *this, AstPointSet *in,
+*                             int forward, AstPointSet *out, int *status )
+
+*  Class Membership:
+*     IntraMap member function (over-rides the astTransform protected
+*     method inherited from the Mapping class).
+
+*  Description:
+*     This function takes a IntraMap and a set of points encapsulated
+*     in a PointSet and transforms the points using the transformation
+*     function associated with the IntraMap.
+
+*  Parameters:
+*     this
+*        Pointer to the IntraMap.
+*     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 IntraMap
+*     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: */
+   astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
+   AstIntraMap *this;            /* Pointer to IntraMap structure */
+   AstMapping *id;               /* Public ID for the IntraMap supplied */
+   AstPointSet *result;          /* Pointer to output PointSet */
+   const double **ptr_in;        /* Pointer to input coordinate data */
+   double **ptr_out;             /* Pointer to output coordinate data */
+   int ncoord_in;                /* Number of coordinates per input point */
+   int ncoord_out;               /* Number of coordinates per output point */
+   int npoint;                   /* Number of points */
+   int ok;                       /* AST status OK? */
+   int status_value;             /* AST status value */
+
+/* Check the global error status. */
+   if ( !astOK ) return NULL;
+
+/* Get a pointer to the thread specific global data structure. */
+   astGET_GLOBALS(this_mapping);
+
+/* Obtain a pointer to the IntraMap structure. */
+   this = (AstIntraMap *) this_mapping;
+
+/* 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)( this_mapping, in, forward, out, status );
+
+/* We will now extend the parent astTransform method by performing the
+   calculations 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. */
+   npoint = astGetNpoint( in );
+   ncoord_in = astGetNcoord( in );
+   ncoord_out = astGetNcoord( result );
+   ptr_in = (const double **) astGetPoints( in );
+   ptr_out = astGetPoints( result );
+
+/* Determine whether to apply the forward or inverse transformation,
+   according to the direction specified and whether the Mapping has
+   been inverted. */
+   if ( astGetInvert( this ) ) forward = !forward;
+
+/* Obtain a public (external) ID for the IntraMap. This will be
+   required (instead of a true C pointer) by the transformation function,
+   since it is user-written. Clone the IntraMap pointer so that the call
+   to astAnnulID later on does not annul the IntraMap pointer. */
+   id = (AstMapping *) astMakeId( astClone( this ) );
+
+/* Locate the transformation function data associated with the
+   IntraMap and use the wrapper function to invoke the transformation
+   function itself. */
+   if ( ( ok = astOK ) ) {
+      LOCK_MUTEX2;
+      ( *tran_data[ this->ifun ].tran_wrap )( tran_data[ this->ifun ].tran,
+                                              id, npoint, ncoord_in, ptr_in,
+                                              forward, ncoord_out, ptr_out,
+                                              status );
+      UNLOCK_MUTEX2;
+
+/* If an error occurred, report a contextual error message. To ensure
+   that the location of the error appears in the message, we first clear
+   the global status (which makes the error system think this is the
+   first report). */
+      if ( !( ok = astOK ) ) {
+         status_value = astStatus;
+         astClearStatus;
+         astError( status_value,
+                   "astTransform(%s): Error signalled by \"%s\" "
+                   "transformation function.", status,
+                   astGetClass( this ), tran_data[ this->ifun ].name );
+      }
+   }
+
+/* Annul the external identifier. */
+   id = astMakeId( astAnnulId( id ) );
+
+/* If an error occurred here, but earlier steps were successful, then
+   something has happened to the external ID, so report a contextual
+   error message. */
+   if ( !astOK && ok ) {
+      astError( astStatus,
+                "astTransform(%s): %s pointer corrupted by \"%s\" "
+                "transformation function.", status,
+                astGetClass( this ), astGetClass( this ),
+                tran_data[ this->ifun ].name );
+   }
+
+/* If an error occurred, clear the returned pointer. If a new output
+   PointSet has been created, then delete it. */
+   if ( !astOK ) {
+      result = ( result == out ) ? NULL : astDelete( result );
+   }
+
+/* Return a pointer to the output PointSet. */
+   return result;
+}
+
+static void TranWrap( void (* tran)( AstMapping *, int, int, const double *[],
+                                     int, int, double *[] ),
+                      AstMapping *this, int npoint, int ncoord_in,
+                      const double *ptr_in[], int forward, int ncoord_out,
+                      double *ptr_out[], int *status ) {
+/*
+*  Name:
+*     TranWrap
+
+*  Purpose:
+*     Wrapper function to invoke a C transformation function.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     void TranWrap( void (* tran)( AstMapping *, int, int, const double *[],
+*                                   int, int, double *[] ),
+*                    AstMapping *this, int npoint, int ncoord_in,
+*                    const double *ptr_in[], int forward, int ncoord_out,
+*                    double *ptr_out[], int *status )
+
+*  Class Membership:
+*     IntraMap member function.
+
+*  Description:
+*     This function invokes a C implementation of a transformation
+*     function (which resembles the astTranP function from the Mapping
+*     class).
+*
+*     This wrapper is essentially a dummy function for the C language.
+*     It may be replaced by alternative versions for foreign language
+*     interfaces, thus allowing transformation functions supplied by
+*     those languages to be invoked without knowledge of their
+*     interfaces.
+
+*  Parameters:
+*     tran
+*        Pointer to the transformation function to be invoked. This
+*        should resemble astTranP (but with the first argument
+*        omitted).
+*     this
+*        An external Mapping ID associated with the internal (true C) pointer
+*        for the IntraMap whose transformation is being evaluated.
+*     npoint
+*        The number of points to be transformed.
+*     ncoord_in
+*        The number of coordinates being supplied for each input point
+*        (i.e. the number of dimensions of the space in which the
+*        input points reside).
+*     ptr_in
+*        An array of pointers to double, with "ncoord_in"
+*        elements. Element "ptr_in[coord]" should point at the first
+*        element of an array of double (with "npoint" elements) which
+*        contain the values of coordinate number "coord" for each
+*        input (untransformed) point. The value of coordinate number
+*        "coord" for input point number "point" is therefore given by
+*        "ptr_in[coord][point]".
+*     forward
+*        A non-zero value indicates that the forward coordinate
+*        transformation is to be applied, while a zero value indicates
+*        that the inverse transformation should be used.
+*     ncoord_out
+*        The number of coordinates being generated for each output
+*        point (i.e. the number of dimensions of the space in which
+*        the output points reside). This need not be the same as
+*        "ncoord_in".
+*     ptr_out
+*        An array of pointers to double, with "ncoord_out"
+*        elements. Element "ptr_out[coord]" should point at the first
+*        element of an array of double (with "npoint" elements) into
+*        which the values of coordinate number "coord" for each output
+*        (transformed) point will be written.  The value of coordinate
+*        number "coord" for output point number "point" will therefore
+*        be found in "ptr_out[coord][point]".
+*     status
+*        Pointer to the inherited status value.
+*/
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Invoke the transformation function. */
+   ( *tran )( this, npoint, ncoord_in, ptr_in, forward, ncoord_out, ptr_out );
+}
+
+/* Functions which access class attributes. */
+/* ---------------------------------------- */
+/* Implement member functions to access the attributes associated with
+   this class using the macros defined for this purpose in the
+   "object.h" file. For a description of each attribute, see the class
+   interface (in the associated .h file). */
+
+/*
+*att++
+*  Name:
+*     IntraFlag
+
+*  Purpose:
+*     IntraMap identification string.
+
+*  Type:
+*     Public attribute.
+
+*  Synopsis:
+*     String.
+
+*  Description:
+c     This attribute allows an IntraMap to be flagged so that it is
+c     distinguishable from other IntraMaps. The transformation function
+c     associated with the IntraMap may then enquire the value of this
+c     attribute and adapt the transformation it provides according to the
+c     particular IntraMap involved.
+f     This attribute allows an IntraMap to be flagged so that it is
+f     distinguishable from other IntraMaps. The transformation routine
+f     associated with the IntraMap may then enquire the value of this
+f     attribute and adapt the transformation it provides according to the
+f     particular IntraMap involved.
+*
+c     Although this is a string attribute, it may often be useful to store
+c     numerical values here, encoded as a character string, and to use these
+c     as data within the transformation function. Note, however, that this
+c     mechanism is not suitable for transferring large amounts of data (more
+c     than about 1000 characters) to an IntraMap. For that purpose, global
+c     variables are recommended, although the IntraFlag value can be used to
+c     supplement this approach. The default IntraFlag value is an empty
+c     string.
+f     Although this is a string attribute, it may often be useful to store
+f     numerical values here, encoded as a character string, and to use these
+f     as data within the transformation routine. Note, however, that this
+f     mechanism is not suitable for transferring large amounts of data (more
+f     than about 1000 characters) to an IntraMap. For that purpose, global
+f     variables are recommended, although the IntraFlag value can be used to
+f     supplement this approach. The default IntraFlag value is an empty
+f     string.
+
+*  Applicability:
+*     IntraMap
+*        All IntraMaps have this attribute.
+
+*  Notes:
+c     - A pair of IntraMaps whose transformations may potentially cancel
+c     cannot be simplified to produce a UnitMap (e.g. using astSimplify)
+c     unless they have the same IntraFlag values. The test for equality is
+c     case-sensitive.
+f     - A pair of IntraMaps whose transformations may potentially cancel
+f     cannot be simplified to produce a UnitMap (e.g. using AST_SIMPLIFY)
+f     unless they have the same IntraFlag values. The test for equality is
+f     case-sensitive.
+*att--
+*/
+
+/* Clear the IntraFlag value by freeing the allocated memory and
+   assigning a NULL pointer. */
+astMAKE_CLEAR(IntraMap,IntraFlag,intraflag,astFree( this->intraflag ))
+
+/* Return a pointer to the IntraFlag value. */
+astMAKE_GET(IntraMap,IntraFlag,const char *,NULL,this->intraflag)
+
+/* Set a IntraFlag value by freeing any previously allocated memory,
+   allocating new memory, storing the string and saving the pointer to
+   the copy. */
+astMAKE_SET(IntraMap,IntraFlag,const char *,intraflag,astStore(
+                                                      this->intraflag, value,
+                                                      strlen( value ) +
+                                                      (size_t) 1 ))
+
+/* The IntraFlag value is set if the pointer to it is not NULL. */
+astMAKE_TEST(IntraMap,IntraFlag,( this->intraflag != NULL ))
+
+/* Copy constructor. */
+/* ----------------- */
+static void Copy( const AstObject *objin, AstObject *objout, int *status ) {
+/*
+*  Name:
+*     Copy
+
+*  Purpose:
+*     Copy constructor for IntraMap objects.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     void Copy( const AstObject *objin, AstObject *objout, int *status )
+
+*  Description:
+*     This function implements the copy constructor for IntraMap objects.
+
+*  Parameters:
+*     objin
+*        Pointer to the object to be copied.
+*     objout
+*        Pointer to the object being constructed.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Notes:
+*     -  This constructor makes a deep copy.
+*/
+
+/* Local Variables: */
+   AstIntraMap *in;              /* Pointer to input IntraMap */
+   AstIntraMap *out;             /* Pointer to output IntraMap */
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Obtain pointers to the input and output IntraMaps. */
+   in = (AstIntraMap *) objin;
+   out = (AstIntraMap *) objout;
+
+/* For safety, first clear any references to the input memory from
+   the output IntraMap. */
+   out->intraflag = NULL;
+
+/* If necessary, allocate memory in the output IntraMap and store a
+   copy of the input IntraFlag string. */
+   if ( in->intraflag ) out->intraflag = astStore( NULL, in->intraflag,
+                                                   strlen( in->intraflag ) +
+                                                   (size_t) 1 );
+
+/* If an error occurred, free any allocated memory. */
+   if ( !astOK ) {
+      out->intraflag = astFree( out->intraflag );
+   }
+}
+
+/* Destructor. */
+/* ----------- */
+static void Delete( AstObject *obj, int *status ) {
+/*
+*  Name:
+*     Delete
+
+*  Purpose:
+*     Destructor for IntraMap objects.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     void Delete( AstObject *obj, int *status )
+
+*  Description:
+*     This function implements the destructor for IntraMap objects.
+
+*  Parameters:
+*     obj
+*        Pointer to the object to be deleted.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Notes:
+*     This function attempts to execute even if the global error status is
+*     set.
+*/
+
+/* Local Variables: */
+   AstIntraMap *this;            /* Pointer to IntraMap */
+
+/* Obtain a pointer to the IntraMap structure. */
+   this = (AstIntraMap *) obj;
+
+/* Free the memory used for the IntraFlag string if necessary. */
+   this->intraflag = astFree( this->intraflag );
+}
+
+/* Dump function. */
+/* -------------- */
+static void Dump( AstObject *this_object, AstChannel *channel, int *status ) {
+/*
+*  Name:
+*     Dump
+
+*  Purpose:
+*     Dump function for IntraMap 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 IntraMap class to an output Channel.
+
+*  Parameters:
+*     this
+*        Pointer to the IntraMap 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 Variables: */
+   astDECLARE_GLOBALS             /* Pointer to thread-specific global data */
+   AstIntraMap *this;             /* Pointer to the IntraMap structure */
+   const char *sval;              /* Pointer to string value */
+   int set;                       /* Attribute value set? */
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Get a pointer to the thread specific global data structure. */
+   astGET_GLOBALS(this_object);
+
+/* Obtain a pointer to the IntraMap structure. */
+   this = (AstIntraMap *) this_object;
+
+/* Write out values representing the instance variables for the
+   IntraMap class.  Accompany these with appropriate comment strings,
+   possibly depending on the values being written.*/
+
+/* Transformation function name. */
+/* ----------------------------- */
+   astWriteString( channel, "Fname", 1, 1, tran_data[ this->ifun ].name,
+                   "Name of transformation function" );
+
+/* IntraFlag string. */
+/* ----------------- */
+   set = TestIntraFlag( this, status );
+   sval = set ? GetIntraFlag( this, status ) : astGetIntraFlag( this );
+   astWriteString( channel, "Iflag", set, 0, sval,
+                   "IntraMap identification string" );
+
+/* Purpose string. */
+/* --------------- */
+   astWriteString( channel, "Purp", 1, 1, tran_data[ this->ifun ].purpose,
+                   "Purpose of function" );
+
+/* Author's name. */
+/* -------------- */
+   astWriteString( channel, "Auth", 1, 1, tran_data[ this->ifun ].author,
+                   "Author's name" );
+
+/* Contact details. */
+/* ---------------- */
+   astWriteString( channel, "Cntact", 1, 1, tran_data[ this->ifun ].contact,
+                   "Contact address" );
+}
+
+/* Standard class functions. */
+/* ========================= */
+/* Implement the astIsAIntraMap and astCheckIntraMap functions using the
+   macros defined for this purpose in the "object.h" header file. */
+astMAKE_ISA(IntraMap,Mapping)
+astMAKE_CHECK(IntraMap)
+
+AstIntraMap *astIntraMap_( const char *name, int nin, int nout,
+                           const char *options, int *status, ...) {
+/*
+*++
+*  Name:
+c     astIntraMap
+f     AST_INTRAMAP
+
+*  Purpose:
+*     Create an IntraMap.
+
+*  Type:
+*     Public function.
+
+*  Synopsis:
+c     #include "intramap.h"
+c     AstIntraMap *astIntraMap( const char *name, int nin, int nout,
+c                               const char *options, ... )
+f     RESULT = AST_INTRAMAP( NAME, NIN, NOUT, OPTIONS, STATUS )
+
+*  Class Membership:
+*     IntraMap constructor.
+
+*  Description:
+*     This function creates a new IntraMap and optionally initialises
+*     its attributes.
+*
+c     An IntraMap is a specialised form of Mapping which encapsulates
+c     a privately-defined coordinate transformation function
+c     (e.g. written in C) so that it may be used like any other AST
+c     Mapping. This allows you to create Mappings that perform any
+c     conceivable coordinate transformation.
+f     An IntraMap is a specialised form of Mapping which encapsulates
+f     a privately-defined coordinate transformation routine
+f     (e.g. written in Fortran) so that it may be used like any other
+f     AST Mapping. This allows you to create Mappings that perform any
+f     conceivable coordinate transformation.
+*
+*     However, an IntraMap is intended for use within a single program
+*     or a private suite of software, where all programs have access
+*     to the same coordinate transformation functions (i.e. can be
+*     linked against them). IntraMaps should not normally be stored in
+*     datasets which may be exported for processing by other software,
+*     since that software will not have the necessary transformation
+*     functions available, resulting in an error.
+*
+c     You must register any coordinate transformation functions to be
+c     used using astIntraReg before creating an IntraMap.
+f     You must register any coordinate transformation functions to be
+f     used using AST_INTRAREG before creating an IntraMap.
+
+*  Parameters:
+c     name
+f     NAME = CHARACTER * ( * ) (Given)
+c        Pointer to a null-terminated string containing the name of
+c        the transformation function to use (which should previously
+c        have been registered using astIntraReg). This name is case
+c        sensitive. All white space will be removed before use.
+f        A character string containing the name of the transformation
+f        routine to use (which should previously have been registered
+f        using AST_INTRAREG). This name is case sensitive. All white
+f        space will be removed before use.
+c     nin
+f     NIN = INTEGER (Given)
+c        The number of input coordinates. This must be compatible with
+c        the number of input coordinates accepted by the
+c        transformation function (as specified when this function was
+c        registered using astIntraReg).
+f        The number of input coordinates. This must be compatible with
+f        the number of input coordinates accepted by the
+f        transformation routine (as specified when this routine was
+f        registered using AST_INTRAREG).
+c     nout
+f     NOUT = INTEGER (Given)
+c        The number of output coordinates. This must be compatible
+c        with the number of output coordinates produced by the
+c        transformation function (as specified when this function was
+c        registered using astIntraReg).
+f        The number of output coordinates. This must be compatible
+f        with the number of output coordinates produced by the
+f        transformation routine (as specified when this routine was
+f        registered using AST_INTRAREG).
+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 IntraMap. 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 IntraMap. 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     astIntraMap()
+f     AST_INTRAMAP = INTEGER
+*        A pointer to the new IntraMap.
+
+*  Notes:
+*     - 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 */
+   AstIntraMap *new;             /* Pointer to new IntraMap */
+   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 IntraMap, allocating memory and initialising the
+   virtual function table as well if necessary. */
+   new = astInitIntraMap( NULL, sizeof( AstIntraMap ), !class_init,
+                          &class_vtab, "IntraMap", name, nin, nout );
+
+/* 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
+   IntraMap'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 IntraMap. */
+   return new;
+}
+
+AstIntraMap *astIntraMapId_( const char *name, int nin, int nout,
+                             const char *options, ... ) {
+/*
+*  Name:
+*     astIntraMapId_
+
+*  Purpose:
+*     Create an IntraMap.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     AstIntraMap *astIntraMapId_( const char *name, int nin, int nout,
+*                                  const char *options, ... )
+
+*  Class Membership:
+*     IntraMap constructor.
+
+*  Description:
+*     This function implements the external (public) interface to the
+*     astIntraMap constructor function. It returns an ID value
+*     (instead of a true C pointer) to external users, and must be
+*     provided because astIntraMap_ has a variable argument list which
+*     cannot be encapsulated in a macro (where this conversion would
+*     otherwise occur).
+*
+*     The variable argument list also prevents this function from
+*     invoking astIntraMap_ 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 astIntraMap_.
+
+*  Returned Value:
+*     The ID value associated with the new IntraMap.
+*/
+
+/* Local Variables: */
+   astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
+   AstIntraMap *new;             /* Pointer to new IntraMap */
+   va_list args;                 /* Variable argument list */
+
+   int *status;                  /* Pointer to inherited status value */
+
+/* Get a pointer to the inherited status value. */
+   status = astGetStatusPtr;
+
+/* Get a pointer to the thread specific global data structure. */
+   astGET_GLOBALS(NULL);
+
+/* Check the global status. */
+   if ( !astOK ) return NULL;
+
+/* Initialise the IntraMap, allocating memory and initialising the
+   virtual function table as well if necessary. */
+   new = astInitIntraMap( NULL, sizeof( AstIntraMap ), !class_init,
+                          &class_vtab, "IntraMap", name, nin, nout );
+
+/* 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
+   IntraMap'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 IntraMap. */
+   return astMakeId( new );
+}
+
+
+AstIntraMap *astInitIntraMap_( void *mem, size_t size, int init,
+                               AstIntraMapVtab *vtab, const char *name,
+                               const char *fname, int nin, int nout, int *status ) {
+/*
+*+
+*  Name:
+*     astInitIntraMap
+
+*  Purpose:
+*     Initialise an IntraMap.
+
+*  Type:
+*     Protected function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     AstIntraMap *astInitIntraMap( void *mem, size_t size, int init,
+*                                   AstIntraMapVtab *vtab, const char *name,
+*                                   const char *fname, int nin, int nout )
+
+*  Class Membership:
+*     IntraMap initialiser.
+
+*  Description:
+*     This function is provided for use by class implementations to
+*     initialise a new IntraMap object. It allocates memory (if
+*     necessary) to accommodate the IntraMap plus any additional data
+*     associated with the derived class.  It then initialises a
+*     IntraMap 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 IntraMap at the start of the memory passed
+*     via the "vtab" parameter.
+
+*  Parameters:
+*     mem
+*        A pointer to the memory in which the IntraMap is to be
+*        initialised.  This must be of sufficient size to accommodate
+*        the IntraMap data (sizeof(IntraMap)) 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 IntraMap (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 IntraMap structure, so a valid value must be
+*        supplied even if not required for allocating memory.
+*     init
+*        A logical flag indicating if the IntraMap'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 IntraMap.
+*     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).
+*     fname
+*        Pointer to a null-terminated string containing the name of
+*        the transformation function to be used, as previously
+*        registered using astIntraReg.
+*     nin
+*        The number of input coordinates.
+*     nout
+*        The number of output coordinates.
+
+*  Returned Value:
+*     A pointer to the new IntraMap.
+
+*  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 Variables: */
+   astDECLARE_GLOBALS             /* Pointer to thread-specific global data */
+   AstIntraMap *new;              /* Pointer to new IntraMap */
+   char *clname;                  /* Cleaned transformation function name */
+   int found;                     /* Transformation function name found? */
+   int ifun;                      /* Loop counter for registered functions */
+
+/* Initialise. */
+   new = NULL;
+
+/* Check the global status. */
+   if ( !astOK ) return NULL;
+
+/* Get a pointer to the thread specific global data structure. */
+   astGET_GLOBALS(NULL);
+
+/* Initialise variables to avoid "used of uninitialised variable"
+   messages from dumb compilers. */
+   found = 0;
+   ifun = 0;
+
+/* If necessary, initialise the virtual function table. */
+   if ( init ) astInitIntraMapVtab( vtab, name );
+
+/* Clean (and validate) the transformation function name supplied. */
+   clname = CleanName( fname, "astIntraMap", status );
+
+/* Search for a registered transformation function name which matches. */
+   if ( astOK ) {
+      found = 0;
+      for ( ifun = 0; ifun < tran_nfun; ifun++ ) {
+         if ( ( found = !strcmp( clname, tran_data[ ifun ].name ) ) ) break;
+      }
+   }
+
+/* Free the memory containing the cleaned name string. */
+   clname = astFree( clname );
+
+/* If no match was found, then report an error. */
+   if ( astOK ) {
+      if ( !found ) {
+         astError( AST__URITF, "astInitIntraMap(%s): The transformation "
+                               "function \"%s\" has not been registered using "
+                               "astIntraReg.", status, name, clname );
+
+/* Check that the number of input coordinates is compatible with the
+   number used by the transformation function (as specified when it
+   was registered). Report an error if necessary. */
+      } else {
+         if ( ( nin != tran_data[ ifun ].nin ) &&
+              ( tran_data[ ifun ].nin != AST__ANY ) ) {
+            astError( AST__BADNI, "astInitIntraMap(%s): Number of input "
+                                  "coordinates (%d) does not match the number "
+                                  "used by the \"%s\" transformation function "
+                                  "(%d).", status, name, nin, tran_data[ ifun ].name,
+                                  tran_data[ ifun ].nin  );
+
+/* Similarly check the number of output coordinates. */
+         } else if ( ( nout != tran_data[ ifun ].nout ) &&
+                     ( tran_data[ ifun ].nout != AST__ANY ) ) {
+            astError( AST__BADNO, "astInitIntraMap(%s): Number of output "
+                                  "coordinates (%d) does not match the number "
+                                  "used by the \"%s\" transformation function "
+                                  "(%d).", status, name, nout, tran_data[ ifun ].name,
+                                  tran_data[ ifun ].nout  );
+
+/* If OK, initialise a Mapping structure (the parent class) as the
+   first component within the IntraMap structure, allocating memory if
+   necessary (note that this also provides further checks on the
+   validity of "nin" and "nout"). Specify whether the forward and
+   inverse transformations are defined. */
+         } else {
+            new = (AstIntraMap *) astInitMapping( mem, size, 0,
+                     (AstMappingVtab *) vtab, name, nin, nout,
+                     ( ( tran_data[ ifun ].flags & AST__NOFWD ) == 0 ),
+                     ( ( tran_data[ ifun ].flags & AST__NOINV ) == 0 ) );
+
+            if ( astOK ) {
+
+/* Initialise the IntraMap data. */
+/* ---------------------------- */
+/* Initialise the IntraFlag string pointer. */
+               new->intraflag = NULL;
+
+/* Store the index used to access the transformation function data. */
+               new->ifun = ifun;
+
+/* If an error occurred, clean up by deleting the new IntraMap. */
+               if ( !astOK ) new = astDelete( new );
+            }
+         }
+      }
+   }
+
+/* Return a pointer to the new IntraMap. */
+   return new;
+}
+
+AstIntraMap *astLoadIntraMap_( void *mem, size_t size,
+                               AstIntraMapVtab *vtab, const char *name,
+                               AstChannel *channel, int *status ) {
+/*
+*+
+*  Name:
+*     astLoadIntraMap
+
+*  Purpose:
+*     Load an IntraMap.
+
+*  Type:
+*     Protected function.
+
+*  Synopsis:
+*     #include "intramap.h"
+*     AstIntraMap *astLoadIntraMap( void *mem, size_t size,
+*                                    AstIntraMapVtab *vtab, const char *name,
+*                                    AstChannel *channel )
+
+*  Class Membership:
+*     IntraMap loader.
+
+*  Description:
+*     This function is provided to load a new IntraMap 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
+*     IntraMap 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 an IntraMap at the start of the memory
+*     passed via the "vtab" parameter.
+
+
+*  Parameters:
+*     mem
+*        A pointer to the memory into which the IntraMap is to be
+*        loaded.  This must be of sufficient size to accommodate the
+*        IntraMap data (sizeof(IntraMap)) 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 IntraMap (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 IntraMap 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(AstIntraMap) is used instead.
+*     vtab
+*        Pointer to the start of the virtual function table to be
+*        associated with the new IntraMap. If this is NULL, a pointer
+*        to the (static) virtual function table for the IntraMap 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 "IntraMap" is used instead.
+
+*  Returned Value:
+*     A pointer to the new IntraMap.
+
+*  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 Variables: */
+   astDECLARE_GLOBALS             /* Pointer to thread-specific global data */
+   AstIntraMap *new;              /* Pointer to the new IntraMap */
+   char *author;                  /* Pointer to author's name string */
+   char *contact;                 /* Pointer to contact details string */
+   char *fname;                   /* Pointer to transformation function name */
+   char *purpose;                 /* Pointer to purpose comment string */
+   int found;                     /* Function name found? */
+   int ifun;                      /* Loop counter for registered functions */
+   int nin;                       /* Number of IntraMap input coordinates */
+   int nout;                      /* Number of IntraMap output coordinates */
+
+/* Initialise. */
+   new = NULL;
+
+/* Check the global error status. */
+   if ( !astOK ) return new;
+
+/* Get a pointer to the thread specific global data structure. */
+   astGET_GLOBALS(channel);
+
+/* If a NULL virtual function table has been supplied, then this is
+   the first loader to be invoked for this IntraMap. In this case the
+   IntraMap belongs to this class, so supply appropriate values to be
+   passed to the parent class loader (and its parent, etc.). */
+   if ( !vtab ) {
+      size = sizeof( AstIntraMap );
+      vtab = &class_vtab;
+      name = "IntraMap";
+
+/* If required, initialise the virtual function table for this class. */
+      if ( !class_init ) {
+         astInitIntraMapVtab( 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 IntraMap. */
+   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, "IntraMap" );
+
+/* Now read each individual data item from this list. */
+
+/* Transformation function name. */
+/* ----------------------------- */
+      fname = astReadString( channel, "fname", "" );
+
+/* IntraFlag string. */
+/* ----------------- */
+      new->intraflag = astReadString( channel, "iflag", NULL );
+
+/* Purpose string. */
+/* --------------- */
+      purpose = astReadString( channel, "purp", "" );
+
+/* Author's name. */
+/* -------------- */
+      author = astReadString( channel, "auth", "" );
+
+/* Contact details. */
+/* ---------------- */
+      contact = astReadString( channel, "cntact", "" );
+
+/* If OK, search the array of transformation function data to see if
+   the required transformation function has been registered. */
+      if ( astOK ) {
+         found = 0;
+         for ( ifun = 0; ifun < tran_nfun; ifun++ ) {
+            if ( ( found = !strcmp( fname, tran_data[ ifun ].name ) ) ) break;
+         }
+
+/* If the transformation function has not been registered, report an
+   error explaining how to obtain it from the author and register
+   it. */
+         if ( !found ) {
+            astError( AST__URITF, "astLoadIntraMap(%s): An IntraMap was read "
+                                  "which uses an unknown transformation "
+                                  "function.", status, astGetClass( channel ) );
+            astError( AST__URITF, "This is a private extension to the AST "
+                                  "library: to handle it, you must obtain the "
+                                  "source code from its author." , status);
+            astError( AST__URITF, "You can then register it with AST in your "
+                                  "software by calling astIntraReg (see "
+                                  "SUN/211)." , status);
+            astError( AST__URITF, " " , status);
+            astError( AST__URITF, "   Function name:   \"%s\".", status, fname );
+            astError( AST__URITF, "   Purpose:         \"%s\".", status, purpose );
+            astError( AST__URITF, "   Author:          \"%s\".", status, author );
+            astError( AST__URITF, "   Contact address: \"%s\".", status, contact );
+            astError( AST__URITF, " " , status);
+
+/* Obtain the numbers of input and output coordinates for the
+   IntraMap. Use parent methods for this, since if any derived class
+   has overridden these methods it may depend on data that have not
+   yet been loaded. */
+         } else {
+            nin = ( *parent_getnin )( (AstMapping *) new, status );
+            nout = ( *parent_getnout )( (AstMapping *) new, status );
+            if ( astOK ) {
+
+/* Check that the numbers of coordinates are compatible with the
+   numbers used by the transformation function, as specified when it
+   was registered. */
+               if ( ( nin != tran_data[ ifun ].nin ) &&
+                    ( tran_data[ ifun ].nin != AST__ANY ) ) {
+                  astError( AST__BADNI, "astLoadIntraMap(%s): The number of "
+                                        "input coordinates for the IntraMap "
+                                        "read (%d) does not match the number "
+                                        "used by the registered \"%s\" "
+                                        "transformation function (%d).", status,
+                                        astGetClass( channel ), nin,
+                                        tran_data[ ifun ].name,
+                                        tran_data[ ifun ].nin  );
+               } else if ( ( nout != tran_data[ ifun ].nout ) &&
+                           ( tran_data[ ifun ].nout != AST__ANY ) ) {
+                  astError( AST__BADNO, "astLoadIntraMap(%s): The number of "
+                                        "output coordinates for the IntraMap "
+                                        "read (%d) does not match the number "
+                                        "used by the registered \"%s\" "
+                                        "transformation function (%d).", status,
+                                        astGetClass( channel ), nout,
+                                        tran_data[ ifun ].name,
+                                        tran_data[ ifun ].nout  );
+
+/* If OK, store the index used to access the transformation function
+   data. */
+               } else {
+                  new->ifun = ifun;
+               }
+            }
+         }
+      }
+
+/* Free strings allocated by astReadString. */
+      fname = astFree( fname );
+      purpose = astFree( purpose );
+      author = astFree( author );
+      contact = astFree( contact );
+
+/* If an error occurred, clean up by deleting the new IntraMap. */
+      if ( !astOK ) new = astDelete( new );
+   }
+
+/* Return the new IntraMap pointer. */
+   return new;
+}
+
+/* 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. */
+
+
+
+
+