IRQ_FXBIT

Assign a fixed bit number to a quality name

Description:

This routine associates a fixed bit number with a specified quality name. Normally, IRQ manages the allocation of bit numbers to named qualities, but this routine allows the calling application to specify which bit is to be used for a given quality.

By default, a QUALITY-array bit is associated with a quality name only if some pixels hold the quality and some do not hold the quality (i.e. there is a mix of values). Otherwise, a flag is stored in the QUALITY_NAMES structure indicating this, and any quality bit previously associated with the quality name is released for re-use.

This default behaviour is changed by calling this routine. The specified bit number will continue to be associated with the quality name even if all pixels do, or do not, hold the quality.

An error will be returned if the named quality is already associated with a different bit number when this routine is called. An error will also be reported if the specified bit number is already associated with a different quality name.

Invocation

CALL IRQ_FXBIT( LOCS, QNAME, BIT, SET, FIXBIT, STATUS )

Arguments

LOCS(5) = CHARACTER ( ) (Given)
An array of five HDS locators. These locators identify the NDF and the associated quality name information. They should have been obtained using routine IRQ_FIND or routine IRQ_NEW.
QNAME = CHARACTER ( ) (Given)
The quality name to use. Leading blanks are ignored and the search is case-insensitive. The maximum allowed length for quality names is given by symbolic constant IRQ__SZQNM which currently has the value of 15.
BIT = INTEGER (Given)
The bit number to use. The least significant bit is Bit 1, not Bit 0. If a value below 0 or above 8 is supplied, the properties of the quality name are left unchanged, but the FIXBIT value is still returned.
FIXBIT = LOGICAL (Returned)
Returned .TRUE. if the specified quality name had a fixed bit number on entry to this routine, and .FALSE. otherwise.
STATUS = INTEGER (Given and Returned)
The global status.