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<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;">Dear all,
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<div>In both my cost and constraint function I simulate the same system with an input based on the decision variables and some other non-varying user data.</div>
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<div>In the case when the cost and constraint function are called with the same decision variables, to avoid redundant computations, I would would not like to simulate the system twice, but only once. </div>
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<div>I want to use a userdata structure to pass on the simulation results from cost to constraints or vice versa. Therefore I am trying to find out how the algorithm flow works:
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<div><b>Does the IPOPT flow ever call cost and constraint with the same decision variables? If so, which one is called first? </b></div>
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<div>I have modified the hs071 example and I found out that the constraint function is called first and then the cost function is called with the same decision variables. Is this generally the case?</div>
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<div>I have looking into the publications, but was not very succesfull in finding an answer to my question. I am guessing it is quite a common problem, that why I am asking you :).</div>
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<div>I appreciate you help,</div>
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<div>Best regards,</div>
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<div>Martijn Disse</div>
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