def get_bare_stabilizer(H: QubitOperator):
'''
Identify the stabilizer of H.
Currently admits only stabilizer with all z
since hf can only identifies the value of these terms
'''
n = get_number_qubit(H)
pws = []
for pw, _ in H.terms.items():
pws.append(pw)
binvecs = pauli2binvec(pws, n)
nullvecs = binary_null_space(np.array(binvecs))
stabs = []
for vec in nullvecs:
# If is all z
if all(vec[:n] == 0):
stab = QubitOperator.identity()
for i in range(n):
if vec[n + i] == 1:
stab = stab * QubitOperator('Z' + str(i))
stabs.append(stab)
else:
print('Stabilizer with x/y terms ignored. ')
return stabs
def test_binary_null_space():
matrix = np.array(prepare_binary_matrix())
null_basis = binary_null_space(matrix.copy())
# if gets null basis
for vec in null_basis:
assert (all((matrix @ vec.T) % 2 == 0))