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IsSimple - Has the Mapping been simplified?

Description:
This attribute indicates whether a Mapping has been simplified by the AST_SIMPLIFY method. If the IsSimple value is non-zero, then the Mapping has been simplified and so there is nothing to be gained by simplifying it again. Indeed, the AST_SIMPLIFY method will immediately return the Mapping unchanged if the IsSimple attribute indicates that the Mapping has already been simplified.
Type:
Integer (boolean), read-only.
Class Applicability:
Mapping
All Mappings have this attribute.
Frame
All classes of Frame return zero for the IsSimple attribute. This is because changes can be made to a Frame which affect the Mapping represented by the Frame, and so there can be no guarantee that the Mapping may not need re-simplifying. Most non-Frame Mappings, on the other hand, are immutable and so when they are simplified it is certain that they weill remain in a simple state.


next up previous 264
Next: Iwc - Include a Frame representing FITS-WCS intermediate world coordinates?
Up: AST Attribute Descriptions
Previous: IsLonAxis(axis) - Is the specified celestial axis a longitude axis?

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