def pwc(model: Model, gen: Generator, instr: Instruction) -> Dict:
"""
Solve the equation of motion (Lindblad or Schrรถdinger) for a given control
signal and Hamiltonians.
Parameters
----------
signal: dict
Waveform of the control signal per drive line.
gate: str
Identifier for one of the gates.
Returns
-------
unitary
Matrix representation of the gate.
"""
signal = gen.generate_signals(instr)
# Why do I get 0.0 if I print gen.resolution here?! FR
ts = []
if model.controllability:
h0, hctrls = model.get_Hamiltonians()
signals = []
hks = []
for key in signal:
signals.append(signal[key]["values"])
ts = signal[key]["ts"]
hks.append(hctrls[key])
signals = tf.cast(signals, tf.complex128)
hks = tf.cast(hks, tf.complex128)
else:
h0 = model.get_Hamiltonian(signal)
ts_list = [sig["ts"][1:] for sig in signal.values()]
ts = tf.constant(tf.math.reduce_mean(ts_list, axis=0))
hks = None
signals = None
if not np.all(
tf.math.reduce_variance(ts_list, axis=0) < 1e-5 * (ts[1] - ts[0])
):
raise Exception("C3Error:Something with the times happend.")
if not np.all(
tf.math.reduce_variance(ts[1:] - ts[:-1]) < 1e-5 * (ts[1] - ts[0])
):
raise Exception("C3Error:Something with the times happend.")
dt = tf.constant(ts[1].numpy() - ts[0].numpy(), dtype=tf.complex128)
batch_size = tf.constant(len(h0), tf.int32)
dUs = tf_batch_propagate(h0, hks, signals, dt, batch_size=batch_size)
U = tf_matmul_left(tf.cast(dUs, tf.complex128))
if model.max_excitations:
U = model.blowup_excitations(tf_matmul_left(tf.cast(dUs, tf.complex128)))
dUs = tf.vectorized_map(model.blowup_excitations, dUs)
return {"U": U, "dUs": dUs, "ts": ts}
def rk4(model: Model, gen: Generator, instr: Instruction, init_state=None) -> Dict:
prop_res = 2
dim = model.tot_dim
Hs = []
ts = []
dUs = []
dict_vals = get_hs_of_t_ts(model, gen, instr, prop_res)
Hs = dict_vals["Hs"]
ts = dict_vals["ts"]
dt = dict_vals["dt"]
dUs = gen_dus_rk4(Hs, dt, dim)
U = gen_u_rk4(Hs, dt, dim)
if model.max_excitations:
U = model.blowup_excitations(U)
dUs = tf.vectorized_map(model.blowup_excitations, dUs)
return {"U": U, "dUs": dUs, "ts": ts}
