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For many engineering optimisation problems, we do not need the exact global optimum. Instead we are interested in a good enough solution. PGSL is an attractive solution technique in such situations. It can be used to solve black box optimization problems where the objective function might not be written in the form of neat mathematical expressions. The objective function might require calling an external program and it may not be possible to compute derivatives and other mathematical characteristics. I developed PGSL in 1998 when I was working at EPFL. Since then it has been used by many people for various tasks. This includes design, control, parameter identification, diagnosis and solving inverse problems. Over the years, I have developed interfaces to PGSL in many languages, for example, matlab, java, VBA, etc. In order to download these versions and other information please see the links below.
You might also be interested in RRPExplorer  The multicriteria decision making tool that I have developed.