def qft_be(self, qreg: QRegisterBE, qcirc: QuantumCircuit) -> QFTGate:
"""Add a QFTGate."""
self._check_qreg(qreg)
gate = self._attach(QFTGate(qreg, qcirc))
# Here the QFT algorithm reversed the endianness, so as we don't want some
# register with a strange behaviour (registers of type QRegisterBE that are
# in little-endian for example), we reverse the endianness.
qreg._reverse_access_endian()
return gate
def iqft_be(self, qreg: QRegisterBE, qcirc: QuantumCircuit) -> QFTGate:
"""Add an inverted QFTBEGate."""
self._check_qreg(qreg)
# The QFT algorithm reverse the endianness, so the inverse QFT algorithm
# also
# and as it is the inverse algorithm, the endianness swap should occurs
# before
# the inverse QFT algorithm.
qreg._reverse_access_endian()
return self._attach(QFTGate(qreg, qcirc).inverse())
def iapproximate_qft_be(self, qreg: QRegisterBE, qcirc: QuantumCircuit,
approximation: int = None) -> ApproximateQFTGate:
"""Add an inverted ApproximateQFTGate."""
self._check_qreg(qreg)
# The QFT algorithm reverse the endianness, so the inverse QFT algorithm
# also
# and as it is the inverse algorithm, the endianness swap should occurs
# before
# the inverse QFT algorithm.
qreg._reverse_access_endian()
return self._attach(
ApproximateQFTGate(qreg, qcirc, approximation).inverse())