[Cilib-users] mutation for PSO

[myriam a. <lab...@gm...>]

Hello,
I am trying to evolve integers for an allocation problem, Z(0,20)^10, and I
tried to specific MutationPositionUpdateStrategy but unfortunately it does
not seem to work for integers. See trace below. Is there a rational for that
that I'm missing? I was thinking that instead of evolving a position by
incremental velocity changes, mutation would sometimes just produce a new
integer. Please let me know if that makes sense. It wouldn't be too hard to
implement it on my end.

Exception in thread "main" java.lang.ClassCastException:
net.sourceforge.cilib.type.types.Int cannot be cast to
net.sourceforge.cilib.type.types.Real
    at
net.sourceforge.cilib.pso.positionupdatestrategies.MutationPositionUpdateStrategy.mutate(MutationPositionUpdateStrategy.java:141)
    at
net.sourceforge.cilib.pso.positionupdatestrategies.MutationPositionUpdateStrategy.updatePosition(MutationPositionUpdateStrategy.java:118)
    at
net.sourceforge.cilib.pso.particle.StandardParticle.updatePosition(StandardParticle.java:156)
    at
net.sourceforge.cilib.pso.iterationstrategies.SynchronousIterationStrategy.performIteration(SynchronousIterationStrategy.java:70)
    at
net.sourceforge.cilib.pso.iterationstrategies.SynchronousIterationStrategy.performIteration(SynchronousIterationStrategy.java:36)
    at net.sourceforge.cilib.pso.PSO.algorithmIteration(PSO.java:125)
    at
net.sourceforge.cilib.algorithm.Algorithm.performIteration(Algorithm.java:140)
    at net.sourceforge.cilib.algorithm.Algorithm.run(Algorithm.java:182)
    at
mil.navy.nrl.optimization.route.RoutePlanning.run(RoutePlanning.java:142)
    at
mil.navy.nrl.optimization.route.RoutePlanning.main(RoutePlanning.java:192)