Hello!<br><br>I have often seen a large difference in performance of Ipopt, not just in the time per iteration, but in the number of iterations between the different linear solvers.<br><br>Do you have a simple explaination for this? I mean, since they are all direct sparse linear solvers, one would expect the linear system to be solved with high accuracy, and then it shouldn't really matter for Ipopt, which solver is used.<br>
<br>With some kind of iterative refinement of the solution, would you then expect all of the solvers to perform equally (again, not in terms of time, but in the steps taken)?<br><br>Best,<br>Joel<br><br>-- <br>Joel Andersson, PhD Student<br>
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