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astGetFrame - Obtain a pointer to a specified Frame in a FrameSet

Description:
This function returns a pointer to a specified Frame in a FrameSet.

Synopsis:
AstFrame *astGetFrame( AstFrameSet *this, int iframe )

Parameters:
this
Pointer to the FrameSet.
iframe
The index of the required Frame within the FrameSet. This value should lie in the range from 1 to the number of Frames in the FrameSet (as given by its Nframe attribute).

Returned Value:
astGetFrame()
A pointer to the requested Frame.

Notes:
  • A value of AST__BASE or AST__CURRENT may be given for the "iframe" parameter to specify the base Frame or the current Frame respectively.
  • This function increments the RefCount attribute of the selected Frame by one.
  • 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 up previous
Next: astGetMapping - Obtain a Mapping that converts between two Frames in a FrameSet
Up: AST Function Descriptions
Previous: astGetActiveUnit - Determines how the Unit attribute will be used

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