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Seed - Random number seed for a MathMap

Description:
This attribute, which may take any integer value, determines the sequence of random numbers produced by the random number functions in MathMap expressions. It is set to an unpredictable default value when a MathMap is created, so that by default each MathMap uses a different set of random numbers.

If required, you may set this Seed attribute to a value of your choosing in order to produce repeatable behaviour from the random number functions. You may also enquire the Seed value (e.g. if an initially unpredictable value has been used) and then use it to reproduce the resulting sequence of random numbers, either from the same MathMap or from another one.

Clearing the Seed attribute gives it a new unpredictable default value.

Type:
Integer.
Class Applicability:
MathMap
All MathMaps have this attribute.


next up previous 264
Next: SideBand - Indicates which sideband a dual sideband spectrum represents
Up: AST Attribute Descriptions
Previous: RootCorner - Specifies which edges of the 3D box should be annotated

AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2009 Science \& Technology Facilities Council