ffsim.qiskit.qiskit_vec_to_ffsim_vec¶

ffsim.qiskit.qiskit_vec_to_ffsim_vec(vec, norb, nelec)[source]¶

Convert a Qiskit state vector to an ffsim state vector.

Parameters:

vec (ndarray) – A state vector in Qiskit format. It should be a one-dimensional vector of length 2 ** (2 * norb) in the spinful case, and 2 ** norb in the spinless case.
norb (int) – The number of spatial orbitals.
nelec (int | tuple[int, int]) – Either a single integer representing the number of fermions for a spinless system, or a pair of integers storing the numbers of spin alpha and spin beta fermions.

Return type:

ndarray