import numpy as np from abp import GraphState from abp import qi, clifford from anders_briegel import graphsim from tqdm import tqdm import random REPEATS = 100000 LOCAL_ROTATION = 0 CZ = 1 MEASURE = 2 def test_single_qubit_measurements(): """ Various simple tests of measurements """ # Test that measuring |0> in Z gives 0 g = GraphState([0]) assert g.measure(0, "pz") == 0, "Measuring |0> in Z gives 0" # Test that measuring |1> in Z gives 1 g = GraphState([0]) g.act_local_rotation(0, "px") assert g.measure(0, "pz") == 1, "Measuring |1> in Z gives 1" # Test that measuring |+> in X gives 0 g = GraphState([0]) g.act_local_rotation(0, "hadamard") assert g.measure(0, "px") == 0 assert g.measure(0, "px") == 0, "Measuring |+> in X gives 0" g.act_local_rotation(0, "pz") assert g.measure(0, "px") == 1, "Measuring |-> in X gives 1" def test_random_outcomes(): """ Testing random behaviour """ ones = 0 for i in range(1000): g = GraphState([0]) g.act_local_rotation(0, "hadamard") ones += g.measure(0, "pz") assert 400 < ones < 600, "This is a probabilistic test!" def test_projection(): """ Test that projection works correctly """ g = GraphState([0]) g.act_local_rotation(0, "hadamard") g.measure(0, "pz", 0) assert np.allclose(g.to_state_vector().state, qi.zero) # Now project onto |1> g = GraphState([0]) g.act_local_rotation(0, "hadamard") g.measure(0, "pz", 1) assert np.allclose(g.to_state_vector().state, qi.one)