def period_helper(a, N, size):
c1 = QubitPlaceholder()
zero = QubitPlaceholder()
x = QubitPlaceholder.register(size)
b = QubitPlaceholder.register(size + 1)
#takes in x and b as zero, finds
p = Program()
n = 2 * size
def_regs = Program()
period_regs = def_regs.declare('ro', 'BIT', n)
#For one reg, we want H, CUA, R_i m_i, X^m_i
for i in range(n - 1, -1, -1):
R = Program()
R += H(c1)
for j in range(i - 1, -1, -1):
k = i - j + 1
doit = Program()
doit += RK(k)(c1).dagger()
R = Program().if_then(period_regs[j], doit, I(c1)) + R
R += MEASURE(c1, period_regs[i])
R += Program().if_then(period_regs[i], X(c1), I(c1))
#R = Program(H(c1)) + R
R = Program(H(c1)) + UA(c1, x, b, a**(2**i), N, zero) + R
p = R + p
p = write_in(1, x) + p
p = def_regs + p
p = get_defs() + p
p = address_qubits(p)
return p
def test_placeholders_preserves_modifiers():
cs = QubitPlaceholder.register(3)
ts = QubitPlaceholder.register(1)
g = X(ts[0])
for c in cs:
g = g.controlled(c).dagger()
p = Program(g)
a = address_qubits(p)
assert a[0].modifiers == g.modifiers
def test_pauli_sum():
q = QubitPlaceholder.register(8)
q_plus = 0.5 * PauliTerm('X', q[0]) + 0.5j * PauliTerm('Y', q[0])
the_sum = q_plus * PauliSum([PauliTerm('X', q[0])])
term_strings = [str(x) for x in the_sum.terms]
assert '(0.5+0j)*I' in term_strings
assert len(term_strings) == 2
assert len(the_sum.terms) == 2
the_sum = q_plus * PauliTerm('X', q[0])
term_strings = [str(x) for x in the_sum.terms]
assert '(0.5+0j)*I' in term_strings
assert len(term_strings) == 2
assert len(the_sum.terms) == 2
the_sum = PauliTerm('X', q[0]) * q_plus
term_strings = [str(x) for x in the_sum.terms]
assert '(0.5+0j)*I' in term_strings
assert len(term_strings) == 2
assert len(the_sum.terms) == 2
with pytest.raises(ValueError):
_ = PauliSum(sI(q[0]))
with pytest.raises(ValueError):
_ = PauliSum([1, 1, 1, 1])
with pytest.raises(ValueError):
_ = the_sum * []
def test_enumerate():
q0, q1, q5 = QubitPlaceholder.register(3)
term = PauliTerm("Z", q0, 1.0) * PauliTerm("Z", q1, 1.0) * PauliTerm(
"X", q5, 5)
position_op_pairs = [(q0, "Z"), (q1, "Z"), (q5, "X")]
for key, val in term:
assert (key, val) in position_op_pairs
def test_exponentiate_identity():
q = QubitPlaceholder.register(11)
mapping = {qp: Qubit(i) for i, qp in enumerate(q)}
generator = PauliTerm("I", q[1], 0.0)
para_prog = exponential_map(generator)
prog = para_prog(1)
result_prog = Program().inst()
assert address_qubits(prog,
mapping) == address_qubits(result_prog, mapping)
generator = PauliTerm("I", q[1], 1.0)
para_prog = exponential_map(generator)
prog = para_prog(1)
result_prog = Program().inst(
[X(q[0]), PHASE(-1.0, q[0]),
X(q[0]), PHASE(-1.0, q[0])])
assert address_qubits(prog,
mapping) == address_qubits(result_prog, mapping)
generator = PauliTerm("I", q[10], 0.08)
para_prog = exponential_map(generator)
prog = para_prog(1)
result_prog = Program().inst(
[X(q[0]), PHASE(-0.08, q[0]),
X(q[0]), PHASE(-0.08, q[0])])
assert address_qubits(prog,
mapping) == address_qubits(result_prog, mapping)
def test_exponentiate_3ns():
# testing circuit for 3-terms non-sequential
q = QubitPlaceholder.register(8)
generator = (
PauliTerm("Y", q[0], 1.0)
* PauliTerm("I", q[1], 1.0)
* PauliTerm("Y", q[2], 1.0)
* PauliTerm("Y", q[3], 1.0)
)
para_prog = exponential_map(generator)
prog = para_prog(1)
result_prog = Program().inst(
[
RX(math.pi / 2.0, q[0]),
RX(math.pi / 2.0, q[2]),
RX(math.pi / 2.0, q[3]),
CNOT(q[0], q[2]),
CNOT(q[2], q[3]),
RZ(2.0, q[3]),
CNOT(q[2], q[3]),
CNOT(q[0], q[2]),
RX(-math.pi / 2.0, q[0]),
RX(-math.pi / 2.0, q[2]),
RX(-math.pi / 2.0, q[3]),
]
)
assert address_qubits(prog) == address_qubits(result_prog)
def NN_encode(qubit: QubitPlaceholder,
N: int) -> (Program, List[QubitPlaceholder]):
### qubit: qubit you want to encode (main qubit)
### N: number of qubits you want to encode the main qubit in.
### For N=1, there is no encoding
code_register = QubitPlaceholder.register(
N) # the List[QubitPlaceholder] of the qubits you have encoded into
code_register[0] = qubit
pq = Program()
### creation of GHZ state:
for ii in range(N - 1):
pq += CNOT(code_register[ii], code_register[ii + 1])
for jj in range(N - 1):
pq += H(code_register[jj])
pq += CZ(code_register[jj + 1], code_register[jj])
for kk in range(N - 1):
pq += CNOT(code_register[kk], code_register[-1])
return pq, code_register
def test_operations_as_set():
q = QubitPlaceholder.register(6)
term_1 = PauliTerm("Z", q[0], 1.0) * PauliTerm("Z", q[1], 1.0) * PauliTerm(
"X", q[5], 5)
term_2 = PauliTerm("X", q[5], 5) * PauliTerm("Z", q[0], 1.0) * PauliTerm(
"Z", q[1], 1.0)
assert term_1.operations_as_set() == term_2.operations_as_set()
def detect_error(self, program, qubits):
"""
Detects a bit-flip error on one of the three qubits in a logical qubit register.
Parameters:
program (Program): The program to add the error detection to
qubits (list[QubitPlaceholder]): The logical qubit register to check for errors
Returns:
A MemoryReference list representing the parity measurements. The first one
contains the parity of qubits 0 and 1, and the second contains the parity
of qubits 0 and 2.
"""
# The plan here is to check if q0 and q1 have the same parity (00 or 11), and if q0 and q2
# have the same parity. If both checks come out true, then there isn't an error. Otherwise,
# if one of the checks reveals a parity discrepancy, we can use the other check to tell us
# which qubit is broken.
parity_qubits = QubitPlaceholder.register(2)
parity_measurement = program.declare("parity_measurement", "BIT", 2)
# Check if q0 and q1 have the same value
program += CNOT(qubits[0], parity_qubits[0])
program += CNOT(qubits[1], parity_qubits[0])
# Check if q0 and q2 have the same value
program += CNOT(qubits[0], parity_qubits[1])
program += CNOT(qubits[2], parity_qubits[1])
# Measure the parity values and return the measurement register
program += MEASURE(parity_qubits[0], parity_measurement[0])
program += MEASURE(parity_qubits[1], parity_measurement[1])
return parity_measurement
def test_commuting_sets():
q = QubitPlaceholder.register(8)
term1 = PauliTerm("X", q[0]) * PauliTerm("X", q[1])
term2 = PauliTerm("Y", q[0]) * PauliTerm("Y", q[1])
term3 = PauliTerm("Y", q[0]) * PauliTerm("Z", q[2])
pauli_sum = term1 + term2 + term3
commuting_sets(pauli_sum)
def correct_errors(self, program, qubits):
"""
Corrects any errors that have occurred within the logical qubit register.
Parameters:
program (Program): The program to add the error correction to
qubits (list[QubitPlaceholder]): The logical qubit register to check and correct
"""
parity_qubits = QubitPlaceholder.register(3)
parity_measurement = program.declare("parity_measurement", "BIT", 3)
# Correct bit flips
self.detect_bit_flip_error(program, qubits, parity_qubits,
parity_measurement)
self.generate_classical_control_corrector(program, qubits,
parity_measurement, X)
for qubit in parity_qubits:
program += RESET(qubit)
# Correct phase flips
self.detect_phase_flip_error(program, qubits, parity_qubits,
parity_measurement)
self.generate_classical_control_corrector(program, qubits,
parity_measurement, Z)
def test_check_commutation_rigorous():
# more rigorous test. Get all operators in Pauli group
p_n_group = ("I", "X", "Y", "Z")
pauli_list = list(product(p_n_group, repeat=3))
pauli_ops = [
list(zip(x, QubitPlaceholder.register(3))) for x in pauli_list
]
pauli_ops_pq = [
reduce(mul, (PauliTerm(*x) for x in op)) for op in pauli_ops
]
non_commuting_pairs = []
commuting_pairs = []
for x in range(len(pauli_ops_pq)):
for y in range(x, len(pauli_ops_pq)):
tmp_op = _commutator(pauli_ops_pq[x], pauli_ops_pq[y])
assert len(tmp_op.terms) == 1
if is_zero(tmp_op.terms[0]):
commuting_pairs.append((pauli_ops_pq[x], pauli_ops_pq[y]))
else:
non_commuting_pairs.append((pauli_ops_pq[x], pauli_ops_pq[y]))
# now that we have our sets let's check against our code.
for t1, t2 in non_commuting_pairs:
assert not check_commutation([t1], t2)
for t1, t2 in commuting_pairs:
assert check_commutation([t1], t2)
def test_multi_control(self):
"""
Tests entanglement with more than one control qubit.
NOTE: This will currently fail because pyQuil has a bug with controlled gates
and QubitPlaceholder: https://github.com/rigetti/pyquil/issues/905
Once that gets fixed, I'll revisit this function.
"""
# Construct the program and the qubits - we're going to use 2 separate registers,
# where one will be a bunch of control qubits and the other will be a single target
# qubit.
valid_states = [
"0000", "0010", "0100", "0110", "1000", "1010", "1100", "1111"
]
controls = QubitPlaceholder.register(len(valid_states[0]) - 1)
target = QubitPlaceholder()
program = Program()
# Hadamard the first three qubits - these will be the controls
for control in controls:
program += H(control)
# pyQuil supports gates that are controlled by arbitrary many qubits, so
# we don't need to mess with Toffoli gates or custom multi-control implementations.
# We just have to chain a bunch of controlled() calls for each control qubit.
gate = X(target)
for control in controls:
gate = gate.controlled(control)
program += gate
# Run the test
self.run_test("multi-controlled operation", program,
controls + [target], 1000, valid_states)
def controlled_modular_multiply(ancilla_cache, program, control, constant,
modulus, multiplier):
"""
This function implements the operation (A*B mod C), where A and C are constants,
and B is a qubit register representing a little-endian integer.
Remarks:
See the Q# source for the "ModularMultiplyByConstantLE" function at
https://github.com/Microsoft/QuantumLibraries/blob/master/Canon/src/Arithmetic/Arithmetic.qs
"""
summand = None
if not "summand" in ancilla_cache:
summand = QubitPlaceholder.register(len(multiplier))
ancilla_cache["summand"] = summand
else:
summand = ancilla_cache["summand"]
program += controlled_modular_add_product(ancilla_cache, control, constant,
modulus, multiplier, summand)
for i in range(0, len(multiplier)):
program += CSWAP(control, summand[i], multiplier[i])
inverse_mod_value = inverse_mod(constant, modulus)
program += controlled_modular_add_product(ancilla_cache, control,
inverse_mod_value, modulus,
multiplier, summand).dagger()
def test_simplify_term_single():
q0, q1, q2 = QubitPlaceholder.register(3)
term = (
PauliTerm("Z", q0) * PauliTerm("I", q1) * PauliTerm("X", q2, 0.5j) * PauliTerm("Z", q0, 1.0)
)
assert term.id() == "X{}".format(q2)
assert term.coefficient == 0.5j
def run_function_in_classical_mode(function, input):
"""
Runs the given function on the provided input, returning the results.
The function will not be run on a superposition on the input, the input
state will directly match what is provided here; thus, this is basically
just running the function classically.
Parameters:
function (function): The black-box function to run the algorithm on (the function being
evaluated). It should take a Program as its first input, an input list[QubitPlaceholder]
as its second argument, and an output list[QubitPlaceholder] as its third argument.
input (list[bool]): The bit string you want to provide as input to the function
Returns:
A bit string representing the measured result of the function.
"""
# Construct the program and registers
input_size = len(input)
input_register = QubitPlaceholder.register(input_size)
output = QubitPlaceholder.register(input_size)
program = Program()
# Sets up the input register so it has the requested input state,
# and runs the function on it.
for i in range(0, input_size):
if input[i]:
program += X(input_register[i])
function(program, input_register, output)
measurement = program.declare("ro", "BIT", input_size)
for i in range(0, input_size):
program += MEASURE(output[i], measurement[i])
# Run the program
assigned_program = address_qubits(program)
computer = get_qc(f"{input_size * 2}q-qvm", as_qvm=True)
executable = computer.compile(assigned_program)
results = computer.run(executable)
# Return the measurement as a list[bool] for classical postprocessing
for result in results:
measurement = [False] * input_size
for i in range(0, input_size):
measurement[i] = (result[i] == 1)
return measurement
def test_exponentiate_commuting_pauli_sum():
q = QubitPlaceholder.register(8)
pauli_sum = PauliSum(
[PauliTerm('Z', q[0], 0.5),
PauliTerm('Z', q[1], 0.5)])
prog = Program().inst(RZ(1., q[0])).inst(RZ(1., q[1]))
result_prog = exponentiate_commuting_pauli_sum(pauli_sum)(1.)
assert address_qubits(prog) == address_qubits(result_prog)
def test_simplify_terms():
q = QubitPlaceholder.register(1)
term = PauliTerm('Z', q[0]) * -1.0 * PauliTerm('Z', q[0])
assert term.id() == ''
assert term.coefficient == -1.0
term = PauliTerm('Z', q[0]) + PauliTerm('Z', q[0], 1.0)
assert str(term).startswith('(2+0j)*Zq')
def test_ids_no_sort():
q = QubitPlaceholder.register(6)
term_1 = PauliTerm("Z", q[0], 1.0) * PauliTerm("Z", q[1], 1.0) * PauliTerm(
"X", q[5], 5)
term_2 = PauliTerm("X", q[5], 5) * PauliTerm("Z", q[0], 1.0) * PauliTerm(
"Z", q[1], 1.0)
assert re.match('Z.+Z.+X.+', term_1.id(sort_ops=False))
assert re.match('X.+Z.+Z.+', term_2.id(sort_ops=False))
def test_get_qubits():
q = QubitPlaceholder.register(2)
term = PauliTerm("Z", q[0]) * PauliTerm("X", q[1])
assert term.get_qubits() == q
q10 = QubitPlaceholder()
sum_term = PauliTerm("X", q[0], 0.5) + 0.5j * PauliTerm("Y", q10) * PauliTerm("Y", q[0], 0.5j)
assert sum_term.get_qubits() == [q[0], q10]
def test_exponentiate_1():
# test rotation of single qubit
q = QubitPlaceholder.register(8)
generator = PauliTerm("Z", q[0], 1.0)
para_prog = exponential_map(generator)
prog = para_prog(1)
result_prog = Program().inst(RZ(2.0, q[0]))
assert address_qubits(prog) == address_qubits(result_prog)
def test_ids():
q = QubitPlaceholder.register(6)
term_1 = PauliTerm("Z", q[0], 1.0) * PauliTerm("Z", q[1], 1.0) * PauliTerm("X", q[5], 5)
term_2 = PauliTerm("X", q[5], 5) * PauliTerm("Z", q[0], 1.0) * PauliTerm("Z", q[1], 1.0)
# Not sortable
with pytest.raises(TypeError):
with pytest.warns(FutureWarning):
term_1.id() == term_2.id()
def test_simplify_warning():
q = QubitPlaceholder.register(8)
t1 = sZ(q[0]) * sZ(q[1])
t2 = sZ(q[1]) * sZ(q[0])
with pytest.warns(UserWarning) as e:
tsum = t1 + t2
assert tsum == 2 * sZ(q[0]) * sZ(q[1])
assert 'will be combined with' in str(e[0].message)
def test_simplify_term_multindex():
q0, q2 = QubitPlaceholder.register(2)
term = (
PauliTerm("X", q0, coefficient=-0.5)
* PauliTerm("Z", q0, coefficient=-1.0)
* PauliTerm("X", q2, 0.5)
)
assert term.id(sort_ops=False) == "Y{q0}X{q2}".format(q0=q0, q2=q2)
assert term.coefficient == -0.25j
def test_ids():
q = QubitPlaceholder.register(6)
term_1 = PauliTerm("Z", q[0], 1.0) * PauliTerm("Z", q[1], 1.0) * PauliTerm(
"X", q[5], 5)
term_2 = PauliTerm("X", q[5], 5) * PauliTerm("Z", q[0], 1.0) * PauliTerm(
"Z", q[1], 1.0)
with pytest.raises(TypeError):
# Not sortable
t = term_1.id() == term_2.id()
def test_check_commutation():
q = QubitPlaceholder.register(8)
term1 = PauliTerm("X", q[0]) * PauliTerm("X", q[1])
term2 = PauliTerm("Y", q[0]) * PauliTerm("Y", q[1])
term3 = PauliTerm("Y", q[0]) * PauliTerm("Z", q[2])
# assert check_commutation(PauliSum([term1]), term2)
assert check_commutation([term2], term3)
assert check_commutation([term2], term3)
assert not check_commutation([term1], term3)
def test_exponentiate_bp1_XZ():
# testing change of basis position 1
q = QubitPlaceholder.register(8)
generator = PauliTerm("Z", q[0], 1.0) * PauliTerm("X", q[1], 1.0)
para_prog = exponential_map(generator)
prog = para_prog(1)
result_prog = Program().inst(
[H(q[1]), CNOT(q[0], q[1]), RZ(2.0, q[1]), CNOT(q[0], q[1]), H(q[1])]
)
assert address_qubits(prog) == address_qubits(result_prog)
def test_ordered():
q = QubitPlaceholder.register(8)
mapping = {x: i for i, x in enumerate(q)}
term = sZ(q[3]) * sZ(q[2]) * sZ(q[1])
prog = address_qubits(exponential_map(term)(0.5), mapping)
assert prog.out() == "CNOT 3 2\n" \
"CNOT 2 1\n" \
"RZ(1.0) 1\n" \
"CNOT 2 1\n" \
"CNOT 3 2\n"
def test_sum_power():
q = QubitPlaceholder.register(8)
pauli_sum = (sY(q[0]) - sX(q[0])) * (1.0 / np.sqrt(2))
assert pauli_sum**2 == PauliSum([sI(q[0])])
with pytest.raises(ValueError):
_ = pauli_sum**-1
pauli_sum = sI(q[0]) + sI(q[1])
assert pauli_sum**0 == sI(q[0])
# Test to make sure large powers can be computed
pauli_sum**400
def test_term_powers():
for qubit in QubitPlaceholder.register(2):
pauli_terms = [sI(qubit), sX(qubit), sY(qubit), sZ(qubit)]
for pauli_term in pauli_terms:
assert pauli_term**0 == sI(qubit)
assert pauli_term**1 == pauli_term
assert pauli_term**2 == sI(qubit)
assert pauli_term**3 == pauli_term
with pytest.raises(ValueError):
pauli_terms[0]**-1