examples/notebook/linear_solver/linear_programming_example.ipynb
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First, you must install ortools package in this colab.
%pip install ortools
Linear optimization example.
from ortools.linear_solver import pywraplp
def LinearProgrammingExample():
"""Linear programming sample."""
# Instantiate a Glop solver, naming it LinearExample.
solver = pywraplp.Solver.CreateSolver("GLOP")
if not solver:
return
# Create the two variables and let them take on any non-negative value.
x = solver.NumVar(0, solver.infinity(), "x")
y = solver.NumVar(0, solver.infinity(), "y")
print("Number of variables =", solver.NumVariables())
# Constraint 0: x + 2y <= 14.
solver.Add(x + 2 * y <= 14.0)
# Constraint 1: 3x - y >= 0.
solver.Add(3 * x - y >= 0.0)
# Constraint 2: x - y <= 2.
solver.Add(x - y <= 2.0)
print("Number of constraints =", solver.NumConstraints())
# Objective function: 3x + 4y.
solver.Maximize(3 * x + 4 * y)
# Solve the system.
print(f"Solving with {solver.SolverVersion()}")
status = solver.Solve()
if status == pywraplp.Solver.OPTIMAL:
print("Solution:")
print(f"Objective value = {solver.Objective().Value():0.1f}")
print(f"x = {x.solution_value():0.1f}")
print(f"y = {y.solution_value():0.1f}")
else:
print("The problem does not have an optimal solution.")
print("\nAdvanced usage:")
print(f"Problem solved in {solver.wall_time():d} milliseconds")
print(f"Problem solved in {solver.iterations():d} iterations")
LinearProgrammingExample()