gurobi_python_api.py

"""
Run this file to check if the Gurobi solver and the python API has been configured properly.
"""


# maximize
# x + y + 2 z
# subject to
# x + 2 y + 3 z <= 4
# x + y >= 1
# x, y, z binary

import gurobipy as gp
from gurobipy import GRB
import numpy as np

try:
    # Create a new model
    m = gp.Model(" mip1 ")
    # Create variables
    x = m.addVar(vtype=GRB.BINARY, name="x")
    y = m.addVar(vtype=GRB.BINARY, name="y")
    z = m.addVar(vtype=GRB.BINARY, name="z")
    # Set objective
    m.setObjective(x + y + 2 * z, GRB.MAXIMIZE)
    # Add constraint : x + 2 y + 3 z <= 4
    m.addConstr(x + 2 * y + 3 * z <= 4, "c0")
    # Add constraint : x + y >= 1
    m.addConstr(x + y >= 1, "c1")
    # Optimize model
    m.optimize()
    for v in m.getVars():
        print('%s %g ' % (v.varName, v.x))
    print('Obj: %g' % m.objVal)
except gp.GurobiError as e:
    print('Error code ' + str(e.errno) + ': ' + str(e))
except AttributeError:
    print('Encountered an attribute error')