Model without constraints + upper bounds

coin-or / python-mip

Python-MIP: collection of Python tools for the modeling and solution of Mixed-Integer Linear programs

Eclipse Public License 2.0

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Model without constraints + upper bounds #65

Closed pmla closed 4 years ago

pmla commented 4 years ago

This is a valid MIP model that doesn't work with python-mip:

ub = 14  # any positive integer
m = Model("upper_bounds")
x = m.add_var(var_type=INTEGER, ub=ub)
m.objective = maximize(x)
m.optimize()
assert m.status == OptimizationStatus.OPTIMAL
assert round(m.objective_value) == ub

It fails on two levels:

The model class complains that there are no constraints. The upper bound is a constraint though.
The upper bound functionality of the variables doesn't appear to work properly.

pmla commented 4 years ago

This works now. I think I was not running on the current master. Sorry! I have added a test for it in #67