Hello Norliza, Could you share the parameter file you are using? We've been working on fixing some issues <https://github.com/eclab/ecj/issues/31> that affect SPEA2 in ECJ 25, but I'd like to try and reproduce the exact exception you're getting. Thanks, Siggy On Tue, Nov 28, 2017 at 2:52 PM, Norliza Abdullah < [log in to unmask]> wrote: > Hi, > > I am running the moosuite problem using SPEA2 in ECJ25, and this error > occurred (after I change this line for (int i = 0; i < reduceBy.length; i++) > > FloatVectorSpecies is using polynomial mutation as its global mutation > type, but alternative-polynomial-version is not defined. Assuming 'true' > Subpop 0 best fitness of generation Fitness: [-20.82654708545083 > -8.87740942183433] > Strength: 41.0 > Distance: 0.1170973657236295 Fitness: 0.1170973657236295 > Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: -50 > at java.util.ArrayList.elementData(ArrayList.java:418) > at java.util.ArrayList.set(ArrayList.java:446) > at ec.multiobjective.spea2.SPEA2Breeder.buildArchive( > SPEA2Breeder.java:138) > at ec.multiobjective.spea2.SPEA2Breeder.loadElites( > SPEA2Breeder.java:61) > at ec.simple.SimpleBreeder.breedPopulation(SimpleBreeder.java:257) > at ec.simple.SimpleEvolutionState.evolve( > SimpleEvolutionState.java:104) > at ec.EvolutionState.run(EvolutionState.java:482) > at ec.Evolve.main(Evolve.java:773) > > But when I change it back to ECJ previous version it's running fine. The > difference between both SPEA2Breeder.java in ECJ25 and the previous one is > one called individual size (ECJ25) instead of the previous one called > individual length. > -- Ph.D student in Computer Science, George Mason University Web Director, Journal of Mason Graduate Research http://mason.gmu.edu/~escott8/