def expand(self):
weights = self.parameters[0]
with qml.tape.QuantumTape() as tape:
for i, pauli_word in enumerate(
_all_pauli_words_but_identity(len(self.wires))):
PauliRot(weights[i], pauli_word, wires=self.wires)
return tape
def expand(self):
hamiltonian = self.parameters[0]
time = self.parameters[1]
n = self.parameters[2]
pauli = {"Identity": "I", "PauliX": "X", "PauliY": "Y", "PauliZ": "Z"}
theta = []
pauli_words = []
wires = []
for i, term in enumerate(hamiltonian.ops):
word = ""
try:
if isinstance(term.name, str):
word = pauli[term.name]
if isinstance(term.name, list):
word = "".join(pauli[j] for j in term.name)
except KeyError as error:
raise ValueError(
"hamiltonian must be written in terms of Pauli matrices, got {}".format(error)
) from error
# skips terms composed solely of identities
if word.count("I") != len(word):
theta.append((2 * time * hamiltonian.coeffs[i]) / n)
pauli_words.append(word)
wires.append(term.wires)
with qml.tape.QuantumTape() as tape:
for i in range(n):
for j, term in enumerate(pauli_words):
PauliRot(theta[j], term, wires=wires[j])
return tape