error with max function

hello i am working on genetic algorithm program and i am not using the toolbox .as i am trying to calculate the fitness function i have problem with max function the error says (An assignment statement makes an assignment to multiple values, but the expression on the right side of the assignment does not appear to produce multiple values). i use the same function in other program and its works,is the GA initialization causing problem or what ? the beginning of the program include initialization step and GA counter i wrote the max function like this

[master_ant,id]=max(pr,[],2);

pr:250*20 matrix

Answer 1

[Jos (10584)]

What does

which max

tell you? Probably you have overwritten the function.