AmplitudeEstimation.q_factory¶

property AmplitudeEstimation.q_factory¶

Get the Q operator, or Grover-operator for the Amplitude Estimation algorithm, i.e.

Q = -A S_0 A^{-1} S_psi0,

where S_0 reflects about the |0>_n state and S_psi0 reflects about |psi_0>_n. See https://arxiv.org/abs/quant-ph/0005055 for more detail.

If the Q operator is not set, we try to build it from the A operator. If neither the A operator is set, None is returned.