def create_pieces(self):
"""Creates :class:`qibo.core.states.DistributedState` pieces on CPU."""
n = 2**self.nlocal
with K.on_cpu():
self.pieces = [
K.cpu_tensor(K.zeros(n)) for _ in range(self.ndevices)
]
def zero_state(cls, circuit):
"""Creates ``|00...0>`` as a distributed state."""
state = cls(circuit)
state.create_pieces()
with K.on_cpu():
piece = K.initial_state(nqubits=state.nlocal)
state.pieces[0] = K.cpu_tensor(piece, dtype=state.dtype)
return state
def plus_state(cls, circuit):
"""Creates ``|++...+>`` as a distributed state."""
state = cls(circuit)
with K.on_cpu():
n = K.cast(2**state.nlocal, dtype=K.dtypes('DTYPEINT'))
norm = K.cast(2**float(state.nqubits / 2.0))
state.pieces = [
K.cpu_tensor(K.ones(n) / norm) for _ in range(state.ndevices)
]
return state
