openfermion.circuits.uccsd_singlet_get_packed_amplitudes

Convert amplitudes for use with singlet UCCSD

openfermion.circuits.uccsd_singlet_get_packed_amplitudes(
    single_amplitudes, double_amplitudes, n_qubits, n_electrons
)

The output list contains only those amplitudes that are relevant to singlet UCCSD, in an order suitable for use with the function uccsd_singlet_generator.

single_amplitudes ndarray

[NxN] array storing single excitation amplitudes corresponding to t[i,j] * (a_i^\dagger a_j - H.C.)

double_amplitudes ndarray

[NxNxNxN] array storing double excitation amplitudes corresponding to t[i,j,k,l] * (a_i^\dagger a_j a_k^\dagger a_l - H.C.)

n_qubits int

Number of spin-orbitals used to represent the system, which also corresponds to number of qubits in a non-compact map.

n_electrons int

Number of electrons in the physical system.

packed_amplitudes list

List storing the unique single and double excitation amplitudes for a singlet UCCSD operator. The ordering lists unique single excitations before double excitations.