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.
Copyright © 2009 Science and Technology Facilities Council.