next up previous
Next: ARY_SECT - Create an array section
Up: Routine Descriptions
Previous: ARY_SBAD - Set the bad-pixel flag for an array

ARY_SBND  -  Set new pixel-index bounds for an array

Description:
The routine sets new pixel-index bounds for an array (or array section). The number of array dimensions may also be changed. If a base array is specified, then a permanent change is made to the actual data object and this will be apparent through any other array identifiers which refer to it. However, if an identifier for an array section is specified, then its bounds are altered without affecting other arrays.

Invocation:
CALL ARY_SBND( NDIM, LBND, UBND, IARY, STATUS )

Arguments:
NDIM = INTEGER (Given)
New number of array dimensions.
LBND( NDIM ) = INTEGER (Given)
New lower pixel-index bounds of the array.
UBND( NDIM ) = INTEGER (Given)
New upper pixel-index bounds of the array,
IARY = INTEGER (Given)
Array identifier.
STATUS = INTEGER (Given and Returned)
The global status.

Notes:
  • The bounds of an array section cannot be altered while it is mapped for access through the identifier supplied to this routine.

  • The bounds of a base array cannot be altered while any part of it is mapped for access (i.e. even through another identifier).

  • The array 's pixel values (if defined) will be retained for those pixels which lie within both the old and new bounds. Any pixels lying outside the new bounds will be lost (and cannot later be recovered by further changes to the array 's bounds). Any new pixels introduced where the new bounds extend beyond the old ones will be assigned the "bad " value, and the subsequent value of the bad-pixel flag will reflect this.

  • If the bounds of a base array are to be altered and retention of the existing pixel values is not required, then a call to ARY_RESET should be made before calling this routine. This will eliminate any processing which might otherwise be needed to retain the existing values. This step is not necessary with an array section, where no processing of pixel values takes place.



next up previous
Next: ARY_SECT - Create an array section
Up: Routine Descriptions
Previous: ARY_SBAD - Set the bad-pixel flag for an array



ARY A Subroutine Library for Accessing ARRAY Data Structures
Starlink User Note 11
R.F. Warren-Smith
28th April 1998
E-mail:rfws@star.rl.ac.uk