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- Description:
This attribute indicates whether a Mapping is able to transform
coordinates in the "inverse" direction (i.e. converting output
coordinates back into input coordinates). If this attribute is
non-zero, the inverse transformation is available. Otherwise, it
is not.
- Type:
- Integer (boolean), readonly.
- Class Applicability:
-
Mapping
-
All Mappings have this attribute.
-
CmpMap
-
The TranInverse attribute value for a CmpMap is given by the
boolean AND of the value for each component Mapping.
-
FrameSet
-
The TranInverse attribute of a FrameSet applies to the
transformation which converts between the FrameSet's current
Frame and its base Frame (as specified by the Current and
Base attributes). This value is given by the boolean AND of
the TranInverse values which apply to each of the individual
sub-Mappings required to perform this conversion.
The TranInverse attribute value for a FrameSet may therefore
change if a new Base or Current Frame is selected.
- Notes:
-
An error will result if a Mapping with a TranInverse value of
zero is used to transform coordinates in the inverse direction.
Next: Unit(axis) - Axis physical units
Up: AST Attribute Descriptions
Previous: TranForward - Forward transformation defined?
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