On Feb 20, 2014, at 9:40 AM, Emre AYDOĞAN <[log in to unmask]> wrote: > if this is possible, in default crossover class, for example (2)will the crossover > be between first Individual's first tree and thirtieth Individual's first tree? or > (3)can the crossover be first Individual's third tree and thirtieth Individual's sixth > tree? You can do either: but if you want #2 then you may need to modify Crossover so it doesn't verify that the two arrays are the same length when it picks a tree. > if the default crossover class can't do like this, can i manually write my own > Crossover class that do crossover like i said in (3) questions? Of course. Sean