[Clp] bestBasicSequence, pivotRow and theta

[Hok Go]

Hi all,

Running into a problem in ClpSimplexNonlinear where pivotColumn finds a theta of 1e30, bestBasicSequence of -1 and pivotRow of -1. This also causes problems when we start reading from these locations. I've attempted modifications to the perturbation without success and was wondering whether anyone's run into this problem and knows a way around it. Another thing I've tried is scaling the coefficients.

On a side note the barrier solver does not run into memory problems but ends after 201 iterations with a  stopped objective. I've also verified that other solvers can produce a correct answer to this problem and I've appended that solution.

Anyone got any ideas?

Cheers,
Hok

Presolve 2 (0) rows, 21 (0) columns and 42 (0) elements
0  Obj 0 Primal inf 55.6677 (2) Dual inf 0.153707 (21)
2  Obj 0
End of values pass after 2 iterations
2  Obj 0
2  Obj 0
Optimal - objective value 0
0  Obj -5.71266e+017 Dual inf 1.40189e+015 (19)


STATE
optimal
OBJECTIVE
5483597535069.56
SOLUTION
-173.941591973461
252.228299131887
645.768536126273
-479.002236942252
0.372648640617555
-12.3137632778437
1.09779599200074
-0.0512981461901408
-4.95954705298369
-0.662623008913045
-2.48548076636163
-1.3484270133586
0.149873781527723
-0.0198378539000891
4.477576268655
0.47567076116259
0.14752851966193
0.0421460826706324
-0.748317699220338
0.33517340397477
0.300487415965592

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