Next: astMapRemove - Removed a named entry from a KeyMap
Up: AST Function Descriptions
Previous: astMapPutU - Add an entry to a KeyMap with an undefined value
astMapRegion
-
Transform a Region into a new Frame using a given Mapping
- Description:
- This function returns a pointer to a new Region which corresponds to
supplied Region described by some other specified coordinate system. A
Mapping is supplied which transforms positions between the old and new
coordinate systems. The new Region may not be of the same class as
the original region.
- Synopsis:
- AstRegion
astMapRegion( AstRegion
this, AstMapping
map,
AstFrame
frame )
- Parameters:
-
this
-
Pointer to the Region.
-
map
-
Pointer to a Mapping which transforms positions from the
coordinate system represented by the supplied Region to the
coordinate system specified by
"frame".
The supplied Mapping should define both forward and inverse
transformations, and these transformations should form a genuine
inverse pair. That is, transforming a position using the forward
transformation and then using the inverse transformation should
produce the original input position. Some Mapping classes (such
as PermMap, MathMap, SphMap) can result in Mappings for which this
is not true.
-
frame
-
Pointer to a Frame describing the coordinate system in which
the new Region is required.
- Returned Value:
-
astMapRegion()
-
A pointer to a new Region. This Region will represent the area
within the coordinate system specified by
"frame"
which corresponds to the supplied Region.
- Notes:
- The uncertainty associated with the supplied Region is modified
using the supplied Mapping.
- A null Object pointer (AST__NULL) will be returned if this
function is invoked with the AST error status set, or if it
should fail for any reason.
Next: astMapRemove - Removed a named entry from a KeyMap
Up: AST Function Descriptions
Previous: astMapPutU - Add an entry to a KeyMap with an undefined value
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