[Ipopt-tickets] [Ipopt] #287: ipopt call order

[Ipopt]

#287: ipopt call order
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Reporter:  alexho  |      Owner:  ipopt-team
    Type:  defect  |     Status:  new
Priority:  normal  |  Component:  Ipopt
 Version:  3.12    |   Severity:  normal
Keywords:          |
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 Hi,

 First thanks for your time. I'm using the matlab interface for ipopt and I
 have some objective function "objfun" that returns a set of function
 values and gradients [f,g] = objfun().

 To fit this into the framework of ipopt I made two new function handles:

 1) that runs the objective function (producing both function values and
 gradients) and outputs the gradient and saves the function values.

 2) that loads the function values and outputs them.

 I hence supply these two function handles to ipopt. From my point of view
 this may not be the most efficient way.

 My questions are; if I use this structure ipopt might not use linesearch,
 since the function values are loaded in, right? Also when I debug
 ipopt_auxdata.m it begins by calling the gradient function first, is this
 true? I would imagine it  begins by calling the objective function, but it
 does not seem to be the case.  In what order does ipopt do this then?

 Thanks, Alexander.

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Ticket URL: <https://projects.coin-or.org/Ipopt/ticket/287>
Ipopt <http://projects.coin-or.org/Ipopt>
Interior-point optimizer for nonlinear programs.