How do you get fval with iterations out of ga and particleswarm (genetic algorithms and particle swarm)

Currently I have:

[s_best,fval_best] = ga(fhandleformatlab,d_fun,[],[],[],[],lb_fun, ub_fun,[],[],options); 
[s_best,fval_best,~,~] = particleswarm(fhandleformatlab,d_fun,lb_fun, ub_fun,options);

But I want to save the result of fval at each iteration/generation to an array, so I can analyse how fast the algorithm converges to optimum. I cannot see how to get this output into an array in the matlab workspace.

Note - I do not merely want to display the output, which I can do. I cannot figure out how to output it to an array in the workspace so I can plot it, analyse it etc.

Answer 1

[Walter Roberson]

Use an output function; see http://www.mathworks.com/help/gads/genetic-algorithm-options.html

You would initialize an array and you would have the output function append to the array each time it was called. I recommend using nested functions for this purpose so that you avoid the temptation of global variables.

[JMP Phillips]

Hi Walter, I just use the evalin function to append it to a variable in the calling function or workspace each iteration.

[Mark Brandon]

Several years have gone by, but I would be interested in this solution you found. Can provide more detail?