coin-or / Bonmin

Basic Open-source Nonlinear Mixed INteger programming

Home Page:https://coin-or.github.io/Bonmin

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Same problem working with IPOPT but failing with BONMIN

sourav003 opened this issue · comments

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

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).