Next: MatrixMap - Map coordinates by multiplying by a matrix
Up: AST Class Descriptions
Previous: Mapping - Inter-relate two coordinate systems
MathMap
-
Transform coordinates using mathematical expressions
- Description:
A MathMap is a Mapping which allows you to specify a set of forward
and/or inverse transformation functions using arithmetic operations
and mathematical functions similar to those available in C. The
MathMap interprets these functions at run-time, whenever its forward
or inverse transformation is required. Because the functions are not
compiled in the normal sense (unlike an IntraMap), they may be used to
describe coordinate transformations in a transportable manner. A
MathMap therefore provides a flexible way of defining new types of
Mapping whose descriptions may be stored as part of a dataset and
interpreted by other programs.
- Constructor Function:
- astMathMap
-
Inheritance
The MathMap class inherits from the Mapping class.
-
Attributes
In addition to those attributes common to all Mappings, every
MathMap also has the following attributes:
-
Seed: Random number seed
-
SimpFI: Forward-inverse MathMap pairs simplify?
-
SimpIF: Inverse-forward MathMap pairs simplify?
-
Functions
The MathMap class does not define any new functions beyond those
which are applicable to all Mappings.
Next: MatrixMap - Map coordinates by multiplying by a matrix
Up: AST Class Descriptions
Previous: Mapping - Inter-relate two coordinate systems
AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 211
R.F. Warren-Smith & D.S. Berry
30th April 2003
E-mail:ussc@star.rl.ac.uk
Copyright (C) 2003 Central Laboratory of the Research Councils