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AST_UNITMAP - Create a UnitMap

Description:
This function creates a new UnitMap and optionally initialises its attributes.

A UnitMap is a unit (null) Mapping that has no effect on the coordinates supplied to it. They are simply copied. This can be useful if a Mapping is required (e.g. to pass to another routine) but you do not want it to have any effect.

Invocation:
RESULT = AST_UNITMAP( NCOORD, OPTIONS, STATUS )
Arguments:
NCOORD = INTEGER (Given)
The number of input and output coordinates (these numbers are necessarily the same).
OPTIONS = CHARACTER $*$ ( $*$ ) (Given)
A character string containing an optional comma-separated list of attribute assignments to be used for initialising the new UnitMap. The syntax used is identical to that for the AST_SET routine.
STATUS = INTEGER (Given and Returned)
The global status.
Returned Value:
AST_UNITMAP = INTEGER
A pointer to the new UnitMap.
Notes:
  • A null Object pointer (AST__NULL) will be returned if this function is invoked with STATUS set to an error value, or if it should fail for any reason.


next up previous 264
Next: AST_VERSION - Return the version of the AST library being used
Up: AST Routine Descriptions
Previous: AST_UNFORMAT - Read a formatted coordinate value for a Frame axis

AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2009 Science \& Technology Facilities Council