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Same problem working with IPOPT but failing with BONMIN #1

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sourav003 opened this issue Jul 16, 2017 · 1 comment
Open

Same problem working with IPOPT but failing with BONMIN #1

sourav003 opened this issue Jul 16, 2017 · 1 comment

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@sourav003
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Hi
I am trying to solve a mixed-integer non-linear programming problem by using BONMIN package through AMPL platform. The objective function is linear and have several other linear constraints. Only one constraint is non-linear but it is twice or more differentiable. When I tried to solve it using IPOPT solver by issuing the following commands, it works but doesn't produce an integer optimal solution, as expected.

model hyb_cld.mod;
data hyb_cld.dat;
option solver ipopt;
option ipopt_options "linear_solver Pardiso";
solve;

However, when I am using the BONMIN solver next, the solver is halting with the following output.

model hyb_cld.mod;
data hyb_cld.dat;
option solver bonmin;
solve;

Bonmin 1.8.4 using Cbc 2.9.7 and Ipopt 3.12.4


This program contains Ipopt, a library for large-scale nonlinear optimization.
Ipopt is released as open source code under the Eclipse Public License (EPL).
For more information visit http://projects.coin-or.org/Ipopt


NLP0012I
Num Status Obj It time Location
NLP0014I 1 FAILED 583.30161 1 22.484
NLP0014I 1 FAILED 583.30161 1 22.216 resolve robustness
NLP0014I 3 FAILED 583.30161 1 21.167 totot
Cbc0006I The LP relaxation is infeasible or too expensive

"Finished"

bonmin: Infeasible problem

Can anyone please help me in finding a way out from this situation? Do I need to change any particular option for the solver? I have attached my model and data files as well.
AMPL.zip

Thanks in advance.
Regards,
Sourav

@svigerske
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If this is still relevant, then try increasing the log level of the NLP solver to see why Ipopt failed. (https://coin-or.github.io/Bonmin/options_list.html) Maybe you need to set linear_solver Pardiso as Bonmin option, too?

I cannot reproduce with the attached model and data files, as I don't have an AMPL license (and the instance goes beyond their demo limits).

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