package glpk tags 490288 confirmed upstream thanks * Ingo Feinerer <[EMAIL PROTECTED]> [2008-07-11 12:00]:
> Package: glpk > Version: 4.11-1 > Severity: normal > > > The following linear program triggers an assertion and stops the program > without a proper solution: > > var x1 integer; > var x2 integer; > > minimize objective : x1 + x2; > > s.t. constraint : (8^4 - 1) * x1 - 8^4 * x2 = 0; > > s.t. x1NotNegative : x1 >= 1; > s.t. x2NotNegative : x2 >= 1; > > end; > > Output of above program: > > [EMAIL PROTECTED]:~$ glpsol -m bug.mod -o bug.sol > Reading model section from bug.mod... > 11 lines were read > Generating objective... > Generating constraint... > Generating x1NotNegative... > Generating x2NotNegative... > Model has been successfully generated > lpx_simplex: original LP has 4 rows, 2 columns, 6 non-zeros > Objective value = 2.0002442 > OPTIMAL SOLUTION FOUND BY LP PRESOLVER > Integer optimization begins... > Objective function is integral > + 0: mip = not found yet >= -inf (1; 0) > + 6922: mip = not found yet >= 3.000000000e+00 (6924; 0) > Assertion failed: x >= lb; file glpmip2.c; line 230 I confirm the problem with glpk 4.29, which has just been uploaded to unstable. The error message is slightly different: Reading model section from bug.mod... 11 lines were read Generating objective... Generating constraint... Generating x1NotNegative... Generating x2NotNegative... Model has been successfully generated glp_simplex: original LP has 4 rows, 2 columns, 6 non-zeros Objective value = 2.0002442 OPTIMAL SOLUTION FOUND BY LP PRESOLVER Integer optimization begins... + 0: mip = not found yet >= -inf (1; 0) Assertion failed: x >= lb Error detected in file glpios03.c at line 257 Aborted I am therefore forwarding this bug report to the upstream author. Andrew: could you please look at this? Please, respect the Reply-To when replying to this message. Thanks, -- Rafael -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]