[Ipopt] unexpected inequality constraints

[Knut Heidemann]

Hi,

I am currently using pyipopt for solving a quadratic problem with linear
equality constraints.
However, I am puzzled by IPOPTS's statement:

"Number of nonzeros in inequality constraint Jacobian: 1"

There should not be any entry in whatever inequality Jacobian if I am
not having any inequality constraints (g_U = g_L), right?

Maybe that is the reason why I am running into a SEGFAULT when
evaluating the constraint Jacobian? [1]

Does anybody know how to find out what is going on?

Best,
Knut.


[1]:

(gdb)******************************************************************************
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
******************************************************************************

This is Ipopt version 3.11, running with linear solver ma27.

[Callback:E] eval_jac_g
[Callback:R] eval_jac_g(1)
[Callback:R] eval_jac_g
Number of nonzeros in equality constraint Jacobian...:        6
Number of nonzeros in inequality constraint Jacobian.:        1
Number of nonzeros in Lagrangian Hessian.............:        0

[Callback:E] eval_grad_f
[Callback:R] eval_grad_f
[Callback:E] eval_jac_g
[Callback:R] eval_jac_g(2)
[Callback:R] eval_jac_g

Program received signal SIGSEGV, Segmentation fault.
0x00007fffed3b4151 in
Ipopt::GenTMatrix::ComputeRowAMaxImpl(Ipopt::Vector&, bool) const ()
from /home/kheidem1/downloads/ipopt-svn/CoinIpopt/build/lib/libipopt.so.0
(gdb)