How to save results in each iteration and also set a Pareto distance convergence measure in Platypus

Question

I am using Platypus for a multi-objective optimization problem. I would like to:

1. Save results in each iteration.

2. Set a convergence criteria of Pareto distance.

I used to do these easily in the global optimization toolbox of MATLAB.

Expected results would be: 1. To have a text file updated in each iteration in the optimization process. 2. To have have a convergence based of the Pareto distances.

Thanks in advance.