seemps.optimization.gradient_descent#

seemps.optimization.gradient_descent(H, guess, maxiter=1000, tol=1e-13, k_mean=10, tol_variance=1e-14, tol_up=None, strategy=<seemps.state.core.Strategy object>, callback=None)[source]#

Ground state search of Hamiltonian H by gradient descent.

Parameters:
HUnion[MPO, MPOList, MPOSum]

Hamiltonian in MPO form.

stateMPS | MPSSum

Initial guess of the ground state.

maxiterint

Maximum number of iterations (defaults to 1000).

tolfloat

Energy variation that indicates termination (defaults to 1e-13).

tol_upfloat, default = tol

If energy fluctuates up below this tolerance, continue the optimization.

tol_variancefloat

Energy variance target (defaults to 1e-14).

strategyOptional[Strategy]

Linear combination of MPS truncation strategy. Defaults to DESCENT_STRATEGY.

callbackOptional[Callable[[MPS, OptimizeResults],Any]]

A callable called after each iteration (defaults to None).