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A Library for Handling
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Description:
This routine
returns a signed value representing the axis increment from axis value v1 to axis value
v2.
For a simple Frame, this is a trivial operation returning the difference between the two axis values. But
for other derived classes of Frame (such as a SkyFrame) this is not the case.
Invocation
RESULT =
AST_AXDISTANCE( THIS, AXIS, V1, V2, STATUS )
Arguments
THIS = INTEGER (Given)
Pointer
to the Frame.
AXIS = INTEGER (Given)
The index of the axis to which the supplied
values refer. The first axis has index 1.
V1 = DOUBLE PRECISION (Given)
The first
axis value.
V2 = DOUBLE PRECISION (Given)
The second axis value.
STATUS =
INTEGER (Given and Returned)
The global status.
Returned Value
AST_AXDISTANCE =
DOUBLE PRECISION
The distance from the first to the second axis value.
Notes:
-
This function will return a "
bad"
result value (AST__BAD) if any of the input values has this
value.
-
A "
bad"
value will also be returned if this function is invoked with STATUS set to an error value, or if
it should fail for any reason.
Copyright (C) 2014 Science & Technology Facilities Council
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- AST
A Library for Handling
World
Coordinate Systems
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