<div>Dear All</div>
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<div>- Has IPOPT routine that is based on first order KKT optimality condition that essentially doesn't need Hessian or its approximation with quasi-newton?</div>
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<div>- In engineering application, experience shows that first order methods are reasonble and sometimes second order methods do'nt give considrable improvement in expence of their cost (e.g. topology optimization), so my question is that for such problem is it logical that when we have only first derivatives, we use quasi-newton method instead of using pure frist order methods?
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<div>Regards, ... rt.</div>
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