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NormMap - Normalise coordinates using a supplied Frame

Description:
The NormMap class implements a Mapping which normalises coordinate values using the astNorm function of a supplied Frame. The number of inputs and outputs of a NormMap are both equal to the number of axes in the supplied Frame.

The forward and inverse transformation of a NormMap are both defined but are identical (that is, they do not form a real inverse pair in that the inverse transformation does not undo the normalisation, instead it reapplies it). However, the astSimplify function will replace neighbouring pairs of forward and inverse NormMaps by a single UnitMap.

Constructor Function:
astNormMap
Inheritance
The NormMap class inherits from the Mapping class.
Attributes
The MatrixMap class does not define any new attributes beyond those which are applicable to all Mappings.
Functions
The NormMap class does not define any new functions beyond those which are applicable to all Mappings.


next up previous 264
Next: NullRegion - A boundless region within a Frame
Up: AST Class Descriptions
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AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 211
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2009 Science \& Technology Facilities Council