def test_shannon_entropy(self):
"""Test shannon_entropy function"""
input_pvec = np.array([0.5, 0.3, 0.07, 0.1, 0.03])
# Base 2
self.assertAlmostEqual(1.7736043871504037, shannon_entropy(input_pvec))
# Base e
self.assertAlmostEqual(1.229368880382052,
shannon_entropy(input_pvec, np.e))
# Base 10
self.assertAlmostEqual(0.533908120973504,
shannon_entropy(input_pvec, 10))
def test_entropy_density_matrix(self):
"""Test entropy function on density matrix inputs"""
# Density matrix input
rhos = [DensityMatrix(np.diag([0.5] + (n * [0]) + [0.5])) for n in range(1, 5)]
for rho in rhos:
self.assertAlmostEqual(entropy(rho), 1)
self.assertAlmostEqual(entropy(rho, base=2), 1)
self.assertAlmostEqual(entropy(rho, base=np.e), -1 * np.log(0.5))
# Array input
for prob in [0.001, 0.3, 0.7, 0.999]:
rho = np.diag([prob, 1 - prob])
self.assertAlmostEqual(entropy(rho), shannon_entropy([prob, 1 - prob]))
self.assertAlmostEqual(
entropy(rho, base=np.e), shannon_entropy([prob, 1 - prob], base=np.e)
)
self.assertAlmostEqual(entropy(rho, base=2), shannon_entropy([prob, 1 - prob], base=2))
# List input
rho = [[0.5, 0], [0, 0.5]]
self.assertAlmostEqual(entropy(rho), 1)
