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PolyMap - Map coordinates using polynomial functions

Description:
A PolyMap is a form of Mapping which performs a general polynomial transformation. Each output coordinate is a polynomial function of all the input coordinates. The coefficients are specified separately for each output coordinate. The forward and inverse transformations are defined independantly by separate sets of coefficients.
Constructor Function:
astPolyMap
Inheritance
The PolyMap class inherits from the Mapping class.
Attributes
The PolyMap class does not define any new attributes beyond those which are applicable to all Mappings.
Functions
In addition to those functions applicable to all Objects, the following functions may also be applied to all Mappings:

  • astPolyTran: Fit a PolyMap inverse or forward transformation


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Next: Polygon - A polygonal region within a 2-dimensional Frame
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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