coin-or / pulp

A python Linear Programming API
http://coin-or.github.io/pulp/
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report Not Solved/No Solution Exists when scip solver found a feasible solution already #706

Open ben-xj opened 7 months ago

ben-xj commented 7 months ago

For SCIP only, it report Not Solved/No Solution Exists when the solver found a feasible solution already. CBC and Cplex works fine.

i can see from scip output that a feasible solution is found:

SCIP Status : solving was interrupted [time limit reached] Solving Time (sec) : 60.00 Solving Nodes : 458 Primal Bound : -1.69680949699402e+06 (4 solutions) Dual Bound : -3.19371571353679e+06 Gap : 88.22 %

What did you do?

code:

solver = pulp.SCIP(msg=True, keepFiles=False, timeLimit=60)
self.model.solve(solver)
log.info(f'Status: {pulp.LpStatus[self.model.status]}')
status = pulp.LpSolution[self.model.sol_status]
log.info(f'Solution status: {status}')

What did you expect to see?

The best solution at the timelimit.

What did you see instead?

Not Solved/No Solution Exists

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