Lucas Pierezan Magalhães

Model status goes from infeasible to optimal when shutting down presolve

11

**Describe the bug** The attached model is infeasible when run with a presolve and optimal when run without a presolve. Is this a bug or would it be expected somehow?...

Model status goes from infeasible to optimal when shutting down presolve

13

## Description The attached model is infeasible when run with a presolve and optimal when run without a presolve. This only happens when I lower mip_feasibility_tolerance. Is this a bug...

HiGHS solver does not update the model correctly after variable fix/unfix

2

## Summary HiGHS solver does not update the model correctly after a sequence of variable fix/unfix. This only occurs when the treat_fixed_vars_as_params flag is True (the default option). ### Steps...

SCIPAMPL solver does not assign values to all variables

2

## Summary Using the solver obtained by SolverFactory('scip'): If a variable, active in the Pyomo model, does not appear in any constraint (or appears with a coefficient 0) then after...

## Summary I´m solving a pyomo model using scip solver. The scip log indicates primal bounds and dual bounds but with some numerical error message after the lp solver. ...

Appsi HiGHS interface : TeeStream and capture_output causes HiGHS execution to freeze

2

## Summary Hello, I run hundreds of optimizations a day using Pyomo with the HiGHS Appsi interface. Certain optimizations, non-deterministically, cause the thread to freeze without any text output to...