seemps.analysis.hdaf.hdaf_mpo

seemps.analysis.hdaf.hdaf_mpo(num_qubits: int, dx: float | floating, M: int = 10, s0: float | floating | None = None, time: float | floating | complex = 0.0, derivative: int = 0, periodic: bool = True, strategy: Strategy = DEFAULT_STRATEGY) → MPO

Constructs a Matrix Product Operator (MPO) of Hermite Distributed Approximating Functionals (HDAFs). The operator may approximate the identity, a derivative or the free propagator, depending on the values of the derivative and time parameters.

Parameters:

num_qubitsint

The number of qubits to discretize the system.

dxFloat

The grid stepsize.

Mint, default=10

The order of the highest Hermite polynomial (must be an even integer).

s0Float | None, default=None

The width of the HDAF Gaussian weight. If not provided, a suitable width will be computed based on M and dx.

timeFloat, default=0.0

The evolution time of the Free Propagator to approximate.

derivativeint, default=0

The order of the derivative to approximate.

periodicbool, default=True

Whether the grid follows perioidic boundary conditions.

strategyStrategy, default=DEFAULT_STRATEGY

The strategy for the returned MPO. Values of the HDAF below the simplification tolerance of the strategy will be discarded.

Returns:

mpo: MPO

The HDAF approximation to an operator specified by the input parameters.