next up previous 264
Next: astGetRegionFrame - Obtain a pointer to the encapsulated Frame within a Region
Up: AST Function Descriptions
Previous: astGetRefPos - Return the reference position in a specified celestial coordinate system


astGetRegionBounds - Returns the bounding box of Region

Description:
This function returns the upper and lower limits of a box which just encompasses the supplied Region. The limits are returned as axis values within the Frame represented by the Region. The value of the Negated attribute is ignored (i.e. it is assumed that the Region has not been negated).
Synopsis:
void astGetRegionBounds( AstRegion $*$this, double $*$lbnd, double $*$ubnd )
Parameters:
this
Pointer to the Region.
lbnd
Pointer to an array in which to return the lower axis bounds covered by the Region. It should have at least as many elements as there are axes in the Region. If an axis has no lower limit, the returned value will be the largest possible negative value.
ubnd
Pointer to an array in which to return the upper axis bounds covered by the Region. It should have at least as many elements as there are axes in the Region. If an axis has no upper limit, the returned value will be the largest possible positive value.
Notes:
  • The value of the Negated attribute is ignored (i.e. it is assumed that the Region has not been negated).

  • If an axis has no extent on an axis then the lower limit will be returned larger than the upper limit. Note, this is different to an axis which has a constant value (in which case both lower and upper limit will be returned set to the constant value).


next up previous 264
Next: astGetRegionFrame - Obtain a pointer to the encapsulated Frame within a Region
Up: AST Function Descriptions
Previous: astGetRefPos - Return the reference position in a specified celestial coordinate system

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