openfermion.circuits.trotter_operator_grouping

Trotter-decomposes operators into groups without exponentiating.

openfermion.circuits.trotter_operator_grouping(
    hamiltonian,
    trotter_number=1,
    trotter_order=1,
    term_ordering=None,
    k_exp=1.0
)

Operators are still Hermitian at the end of this method but have been multiplied by k_exp.

The default term_ordering is simply the ordered keys of the QubitOperators.terms dict.

hamiltonian (QubitOperator): full hamiltonian trotter_number (int): optional number of trotter steps - default is 1 trotter_order (int): optional order of trotterization as an integer from 1-3 - default is 1 term_ordering (list of (tuples of tuples)): optional list of QubitOperator terms dictionary keys that specifies order of terms when trotterizing k_exp (float): optional exponential factor to all terms when trotterizing

QubitOperator generator

ValueError if order > 3 or order <= 0, TypeError for incorrect types