The problem I'm having is currently with the GMM fit model. but it's rather general. during the run of my program GMM sometimes gives the error of ill conditioned matrix and breaks the code. Now my code is in a long loop with a counter. what I'm doing right now is to manually reset the loop counter in the code body to the last working number, so that the code restarts from the point where it stoped. But it's tedious. Is there a way to tell matlab to do a few basic operations in case of an error and try again, instead of breaking off with an error?