test_qubit.py 文件源码

def test_measure_partial():
    #Basic test of collapse of entangled two qubits (Bell States)
    state = Qubit('01') + Qubit('10')
    assert measure_partial(state, (0,)) == \
        [(Qubit('10'), Rational(1, 2)), (Qubit('01'), Rational(1, 2))]
    assert measure_partial(state, (0,)) == \
        measure_partial(state, (1,))[::-1]

    #Test of more complex collapse and probability calculation
    state1 = sqrt(2)/sqrt(3)*Qubit('00001') + 1/sqrt(3)*Qubit('11111')
    assert measure_partial(state1, (0,)) == \
        [(sqrt(2)/sqrt(3)*Qubit('00001') + 1/sqrt(3)*Qubit('11111'), 1)]
    assert measure_partial(state1, (1, 2)) == measure_partial(state1, (3, 4))
    assert measure_partial(state1, (1, 2, 3)) == \
        [(Qubit('00001'), Rational(2, 3)), (Qubit('11111'), Rational(1, 3))]

    #test of measuring multiple bits at once
    state2 = Qubit('1111') + Qubit('1101') + Qubit('1011') + Qubit('1000')
    assert measure_partial(state2, (0, 1, 3)) == \
        [(Qubit('1000'), Rational(1, 4)), (Qubit('1101'), Rational(1, 4)),
         (Qubit('1011')/sqrt(2) + Qubit('1111')/sqrt(2), Rational(1, 2))]
    assert measure_partial(state2, (0,)) == \
        [(Qubit('1000'), Rational(1, 4)),
         (Qubit('1111')/sqrt(3) + Qubit('1101')/sqrt(3) +
          Qubit('1011')/sqrt(3), Rational(3, 4))]