def test_multiply_expression_and_expression_in_place(self):
e = lp.Expression({'x1': -5, 'x2': 3}, offset=10)
e *= lp.Expression({'x1': 1})
self.assertEqual(e.offset, 0)
self.assertEqual(dict(e.values()), {
lp.Product(['x1', 'x1']): -5,
lp.Product(['x1', 'x2']): 3,
'x1': 10
})
def test_multiply_expression_and_simple_expression(self):
e1 = lp.Expression({'x1': -5, 'x2': 3}, offset=10)
e2 = lp.Expression({'x1': 1})
e = e1 * e2
self.assertEqual(e.offset, 0)
self.assertEqual(dict(e.values()), {
lp.Product(['x1', 'x1']): -5,
lp.Product(['x1', 'x2']): 3,
'x1': 10
})
def test_expression_pow_two_in_place(self):
e = lp.Expression({'x1': -5, 'x2': 3}, offset=10)
e **= 2
self.assertEqual(e.offset, 100)
self.assertEqual(dict(e.values()), {
lp.Product(['x1', 'x1']): 25,
lp.Product(['x1', 'x2']): -30,
lp.Product(['x2', 'x2']): 9,
'x1': -100,
'x2': 60
})
def test_multiply_expression_and_expression(self):
e1 = lp.Expression({'x1': 1, 'x2': 2, 'x3': 3}, offset=4)
e2 = lp.Expression({'x2': 4, 'x4': 5}, offset=-5)
e = e1 * e2
self.assertEqual(e.offset, -20)
self.assertEqual(dict(e.values()), {
lp.Product(['x1', 'x2']): 4,
lp.Product(['x2', 'x2']): 8,
lp.Product(['x2', 'x3']): 12,
lp.Product(['x1', 'x4']): 5,
lp.Product(['x2', 'x4']): 10,
lp.Product(['x3', 'x4']): 15,
'x1': -5,
'x2': 6,
'x3': -15,
'x4': 20
})
def test_result_get_expression_product_value(self):
result = MockResult({'x1': 2, 'x2': 3, 'x3': 4})
expr = lp.Expression({lp.Product(['x1', 'x2']): 3, 'x3': -1}, offset=4)
self.assertEqual(result.get_value(expr), 18)
def test_expression_contains_product(self):
e = lp.Expression({lp.Product(['x1', 'x1']): -1})
self.assertIn(lp.Product(['x1', 'x1']), e)
self.assertNotIn('x1', e)
def test_expression_with_product_to_string(self):
e = lp.Expression({'x1': -4, lp.Product(['x1', 'x2']): 2}, 12)
self.assertEqual(str(e), '-4*x1 + 2*x1*x2 + 12')
