Source code for netket.hilbert.custom_hilbert

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from typing import Optional, List, Callable

from numbers import Real

from netket.graph import AbstractGraph

from .homogeneous import HomogeneousHilbert
from ._deprecations import graph_to_N_depwarn


class CustomHilbert(HomogeneousHilbert):
    r"""A custom hilbert space with discrete local quantum numbers."""

[docs] def __init__( self, local_states: Optional[List[Real]], N: int = 1, constraint_fn: Optional[Callable] = None, graph: Optional[AbstractGraph] = None, ): r""" Constructs a new ``CustomHilbert`` given a list of eigenvalues of the states and a number of sites, or modes, within this hilbert space. Args: local_states (list or None): Eigenvalues of the states. If the allowed states are an infinite number, None should be passed as an argument. N: Number of modes in this hilbert space (default 1). constraint_fn: A function specifying constraints on the quantum numbers. Given a batch of quantum numbers it should return a vector of bools specifying whether those states are valid or not. Examples: Simple custom hilbert space. >>> import netket >>> g = netket.graph.Hypercube(length=10,n_dim=2,pbc=True) >>> hi = netket.hilbert.CustomHilbert(local_states=[-1232, 132, 0], N=100) >>> print(hi.size) 100 """ N = graph_to_N_depwarn(N=N, graph=graph) super().__init__(local_states, N, constraint_fn)
def __pow__(self, n): if self._has_constraint: raise NotImplementedError( """Cannot exponentiate a CustomHilbert with constraints. Construct it from scratch instead.""" ) return CustomHilbert(self._local_states, self.size * n)