Source code for netket.hilbert.custom_hilbert
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# Licensed under the Apache License, Version 2.0 (the "License");
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# http://www.apache.org/licenses/LICENSE-2.0
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from typing import Optional, Callable
from netket.utils import StaticRange
from .homogeneous import HomogeneousHilbert
[docs]
class CustomHilbert(HomogeneousHilbert):
r"""A custom hilbert space with discrete local quantum numbers."""
[docs]
def __init__(
self,
local_states: Optional[StaticRange],
N: int = 1,
constraint_fn: Optional[Callable] = 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: :class:`~netket.utils.StaticRange` object describing the
numbers used to encode the local degree of freedom of this Hilbert
Space.
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.
The :class:`netket.utils.StaticRange` object works like a standard `range`
object and is used to define the valid configurations of the local degrees
of freedom.
For example, the :class:`~netket.utils.StaticRange` of a Fock Hilbert space
is constructed as
.. code-block:: python
>>> import netket as nk
>>> n_max = 10
>>> nk.utils.StaticRange(start=0, step=1, length=n_max)
StaticRange(start=0, step=1, length=10, dtype=int64)
and the range of a Spin-1/2 Hilbert space is constructed as:
.. code-block:: python
>>> import netket as nk
>>> n_max = 10
>>> nk.utils.StaticRange(start=-1, step=2, length=2)
StaticRange(start=-1, step=2, length=2, dtype=int64)
Examples:
Simple custom hilbert space.
>>> import netket as nk
>>> g = nk.graph.Hypercube(length=10,n_dim=2,pbc=True)
>>> local_states = nk.utils.StaticRange(start=-2.0, step=1.0, length=4)
>>> hi = nk.hilbert.CustomHilbert(local_states=local_states, N=100)
>>> print(hi.size)
100
"""
super().__init__(local_states, N, constraint_fn)
def _mul_sametype_(self, other):
assert type(self) == type(other)
if not self.constrained:
if self.local_states == other.local_states:
return CustomHilbert(self._local_states, self.size + other.size)
return NotImplemented