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AR# 2398

PAR M1.5 - PAR appears to ignore soft range constraints


In some cases, PAR appears to ignore soft range constraints,
placing the constrained components outside the specified
range, with no warning message or other indication that this
is happening.

A soft range constraint is a constraint that is used to
guide placement, but PAR will place components elsewhere
if the costing algorithms override the constraint. A hard
range constraint will not be overidden by other factors and
the PAR session will either follow the constraint or error
out if this is not possible.

Reference #11273


PAR does in fact pay attention to soft range constraints
by factoring the constraint into its costing algorithms.
A site outside the specified area may still be the lowest cost
solution even though the soft constraint has increased that
cost. A hard range constraint should be used to guarantee
placement within a range.
AR# 2398
Date Created 08/31/2007
Last Updated 10/06/2008
Status Archive
Type General Article