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AST_REMOVEFRAME - Remove a Frame from a FrameSet   

Description:
This routine removes a Frame from a FrameSet. All other Frames in the FrameSet have their indices re-numbered from one (if necessary), but are otherwise unchanged.

Invocation:
CALL AST_REMOVEFRAME( THIS, IFRAME, STATUS )

Arguments:
THIS = INTEGER (Given)
Pointer to the FrameSet.
IFRAME = INTEGER (Given)
The index within the FrameSet of the Frame to be removed. This value should lie in the range from 1 to the number of Frames in the FrameSet (as given by its Nframe attribute).
STATUS = INTEGER (Given and Returned)
The global status.

Notes:
  • Removing a Frame from a FrameSet does not affect the relationship between other Frames in the FrameSet, even if they originally depended on the Frame being removed.
  • The number of Frames in a FrameSet cannot be reduced to zero. An error will result if an attempt is made to remove the only remaining Frame.
  • A value of AST__BASE or AST__CURRENT may be given for the IFRAME argument to specify the base Frame or the current Frame respectively.
  • If a FrameSet's base or current Frame is removed, the Base or Current attribute (respectively) of the FrameSet will have its value cleared, so that another Frame will then assume its role by default.
  • If any other Frame is removed, the base and current Frames will remain the same. To ensure this, the Base and/or Current attributes of the FrameSet will be changed, if necessary, to reflect any change in the indices of these Frames.



next up previous
Next: AST_RESAMPLE<X> - Resample a region of a data grid
Up: AST Routine Descriptions
Previous: AST_REMAPFRAME - Modify a Frame's relationship to other Frames in a FrameSet

AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
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