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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. If no
inverse transformation is supplied, an iterative method can be used
to evaluate the inverse based only on the forward transformation.
 Constructor Function:
 astPolyMap

Inheritance
 The PolyMap class inherits from the Mapping class.

Attributes
 In addition to those attributes common to all Mappings, every
PolyMap also has the following attributes:
 IterInverse: Provide an iterative inverse transformation?
 NiterInverse: Maximum number of iterations for iterative inverse
 TolInverse: Target relative error for iterative inverse

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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AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 211
R.F. WarrenSmith & D.S. Berry
25th February 2013
Email:starlink@jiscmail.ac.uk
Copyright (C) 2014 Science \& Technology Facilities Council