----- file created by makedoc on: Tue Apr  1 15:29:55 2008
----- Documentation for /scisoft/xop2.3/extensions/shadowvui/src/lib/seed.pro -----

 NAME:
	SEED

 PURPOSE:
	This procedure changes the seed in a source gfile (or its
	associated IDL structure).

 CATEGORY:
	SHADOW

 CALLING SEQUENCE:
 
	seed,input [,seeds]

 OPTIONAL INPUTS:
	input:	either the file name or the IDL structure to be loaded. 

 OPTIONAL OUTPUTS:
	seeds:	a 2-dim array containing the old and the new seeds

 KEYWORD PARAMETERS:

 OUTPUTS:
	None. It changes the file or the structure.

 PROCEDURE:
	extracts the original seed from istar1, and updates it using
	tmp = randomu(istar1)
	istar1=2*istar1+1
 EXAMPLE:

		seed,'start.00'

 MODIFICATION HISTORY:
 	Written by:	Manuel Sanchez del Rio, srio@esrf.fr, 97/11/05
	10/02/2000 changed random generator to randomu1.pro
	19/10/2000 added seeds. Fix a bug: new start seed is not longer
		2*newseed+1 just newseed.

