random production firing

[Christian Lebiere]

> I have 2 productions that I want to fire at random. That is, approximately
> 50% of the time p1 fires, and 50% of the time p2 fires.

An alternative to Niels' solution is to turn on Enable Randomness, e.g.:

(sgp :er t)

Instantiations of equal value are then ordered randomly in the conflict
set.  The advantage is that this works whether or not Rational Analysis is
on.  The disadvantage is that it only works if the production evaluations
are exactly equal.

Christian