terminating with uncaught exception of type std::out_of_range: vector

[noorulhaq]

Problem

[METADATA]

name This is a small test problem
vars 2

[VARIABLES]

0 x1 inf
0 x2 inf

[CONSTRAINTS]

4 2 < 20000
6 10 < 48000
0 1 < 3500

[OBJECTIVE]

maximize 3600 5400

Output

Number of regular constraints: 3
4 2 <= 20000
6 10 <= 48000
0 1 <= 3500

Number of non-negativity constraints: 2
1 0 non-negative
0 1 non-negative

Objective function:
max ( 3600 5400 ) * x

Generating problem in standard form ... done.
Generating artificial problem ... done.
Solving artificial problem ...
Optimal found at step 1.
Done.
Base is clear about artificial variables, proceed ...
Solving problem ...
libc++abi.dylib: terminating with uncaught exception of type std::out_of_range: vector

Reason

Changing the variable value to any other value in second constraint resolves the issue:

from 6 10 < 48000 to 6 10.5 < 48000

[dpar39]

I got as far as finding out that when applying Bland's strategy (search for it in simplex.cc), all reduced costs are non-negative and no column index is selected.

[tunnuz]

@dpar39 thanks for reporting this, I'm not actively mantaining this, but have you found anything else by any chance?