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AST_SHIFTMAP - Create a ShiftMap

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

A ShiftMap is a linear Mapping which shifts each axis by a specified constant value.

Invocation:
RESULT = AST_SHIFTMAP( NCOORD, SHIFT, OPTIONS, STATUS )
Arguments:
NCOORD = INTEGER (Given)
The number of coordinate values for each point to be transformed (i.e. the number of dimensions of the space in which the points will reside). The same number is applicable to both input and output points.
SHIFT( NCOORD ) = DOUBLE PRECISION (Given)
An array containing the values to be added on to the input coordinates in order to create the output coordinates. A separate value should be supplied for each coordinate.
OPTIONS = CHARACTER $*$ ( $*$ ) (Given)
A character string containing an optional comma-separated list of attribute assignments to be used for initialising the new ShiftMap. The syntax used is identical to that for the AST_SET routine.
STATUS = INTEGER (Given and Returned)
The global status.
Returned Value:
AST_SHIFTMAP = INTEGER
A pointer to the new ShiftMap.
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.
Status Handling
The protected interface to this function includes an extra parameter at the end of the parameter list descirbed above. This parameter is a pointer to the integer inherited status variable: "int $*$status".


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Next: AST_SHOW - Display a textual representation of an Object on standard output
Up: AST Routine Descriptions
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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