def test_variable(self):
x = Variable(2)
y = Variable(2)
assert y.name() != x.name()
x = Variable(2, name='x')
y = Variable()
self.assertEqual(x.name(), 'x')
self.assertEqual(x.size, (2,1))
self.assertEqual(y.size, (1,1))
self.assertEqual(x.curvature, u.Curvature.AFFINE)
self.assertEqual(x.canonicalize()[0].size, (2,1))
self.assertEqual(x.canonicalize()[1], [])
# Scalar variable
coeff = self.a.coefficients(self.intf)
self.assertEqual(coeff[self.a], 1)
# Vector variable.
coeffs = x.coefficients(self.intf)
self.assertItemsEqual(coeffs.keys(), [x])
vec = coeffs[x]
self.assertEqual(vec.size, (2,2))
self.assertEqual(list(vec), [1,0,0,1])
# Matrix variable.
coeffs = self.A.coefficients(self.intf)
self.assertItemsEqual(coeffs.keys(), [self.A])
mat = coeffs[self.A]
self.assertEqual(mat.size, (2,2))
self.assertEqual(list(mat), [1,0,0,1])
