next up previous
Next: AST_CLIP - Set up or remove clipping for a Plot
Up: AST Routine Descriptions
Previous: AST_CHANNEL - Create a Channel

AST_CLEAR - Clear attribute values for an Object   

Description:
This routine clears the values of a specified set of attributes for an Object. Clearing an attribute cancels any value that has previously been explicitly set for it, so that the standard default attribute value will subsequently be used instead. This also causes the AST_TEST function to return the value .FALSE. for the attribute, indicating that no value has been set.

Invocation:
CALL AST_CLEAR( THIS, ATTRIB, STATUS )

Arguments:
THIS = INTEGER (Given)
Pointer to the Object.
ATTRIB = CHARACTER * ( * ) (Given)
A character string containing a comma-separated list of the names of the attributes to be cleared.
STATUS = INTEGER (Given and Returned)
The global status.

Class Applicability:
Object
This routine applies to all Objects.

Notes:
  • Attribute names are not case sensitive and may be surrounded by white space.
  • It does no harm to clear an attribute whose value has not been set.
  • An error will result if an attempt is made to clear the value of a read-only attribute.



next up previous
Next: AST_CLIP - Set up or remove clipping for a Plot
Up: AST Routine Descriptions
Previous: AST_CHANNEL - Create a Channel

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