On 13.07.20 17:20, Domingo Alvarez Duarte wrote: > Hello Peter ! > > Till glpk 4.64 this error does not happen, I'm looking through the code > and think that the real fix is to prevent to solve the problem if the > presolver eliminated all columns or rows. > > Cheers ! >
The presolver may find an integer optimal solution. Then the solver stops with: INTEGER OPTIMAL SOLUTION FOUND BY MIP PREPROCESSOR Currently this is only reached if the transformed equation system has zero columns and zero rows (src/draft/glpapi09.c, line 328). In the example the presolved equation system has 0 columns and 1 row. Why is this row is not active and therefore not eliminated in npp_process_prob() (src/npp/npp5.c:651)? Best regards Heinrich
