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SCIP Solver Results undefined/unknown/inf
After solving a model (code here) using SCIP (SCIP version 7.0.1 [precision: 8 byte] [memory: block] [mode: optimized] [LP solver: SoPlex 5.0.1] [GitHash: b41d526acf]), the results components (i.e. gap, bounds, sense) remain undefined or inf, as shown below. The solution is correct though, the same as found with Gurobi (version 9.0.1 build v9.0.1rc0 (mac64)). The bounds and gap shown in the solver output (tee=True) is also the same as in case of Gurobi. What can be done about correctly setting the results object?
solver = pyo.SolverFactory('scip')
results = solver.solve(m, keepfiles=True, tee=True, load_solutions=False)
results.write()
if results.solver.termination_condition == pyo.TerminationCondition.optimal:
m.solutions.load_from(results)
m.pprint()
# ==========================================================
# = Solver Results =
# ==========================================================
# ----------------------------------------------------------
# Problem Information
# ----------------------------------------------------------
Problem:
- Lower bound: -inf
Upper bound: inf
Number of objectives: 1
Number of constraints: 0
Number of variables: 20
Sense: unknown
I have the same issue with SCIP 8.0.0 and Pyomo 6.2.
I also have this same issue with Pyomo 6.6.2 and SCIP 8.0.4.
Problem:
- Lower bound: -inf
Upper bound: 46259048.8645032
Number of objectives: 1
Number of constraints: 0
Number of variables: 97146
Sense: unknown
Solver:
- Status: ok
Message: optimal solution found
Termination condition: optimal
Id: 0
Error rc: 0
Time: 143.75
Gap: 0.0
Primal bound: 46259048.8645032
Dual bound: 46259048.8645032
Solution:
- number of solutions: 0
number of solutions displayed: 0