iraf.net

NUMBER:	528
MODULE:	ARTDATA tasks using random numbers and URAND
SYSTEM:	-V2.12.2
DATE:	Thu Aug  7 12:38:19 MST 2003
FROM:	valdes

BUG:	Many tasks using random numbers in ARTDATA (GALLIST, STARLIST,
	MKNOISE, MKOBJECTS, MK1DSPEC, MKECHELLE) as well as UTILITIES.URAND
	have a parameter to provide the seed value and a feature to specify
	it as INDEF to set it based on the system clock.  This is to allow
	generation of different results each time the task is called.
	However, the clock-based seed only changes each second so if the
	same task is called rapidly enough the seed may not change between
	executions.  The workaround is to include some delay beween calls,
	such as using sleep in scripts and CL loops.

STATUS:	The tasks listed above have been modified for the next release
	to avoid the behavior described above.