Source code for netket.hilbert.qubit

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from typing import Optional, Union, List

from netket.graph import AbstractGraph

from .homogeneous import HomogeneousHilbert
from ._deprecations import graph_to_N_depwarn


class Qubit(HomogeneousHilbert):
    r"""Hilbert space obtained as tensor product of local qubit states."""

[docs] def __init__(self, N: int = 1, graph: Optional[AbstractGraph] = None): r"""Initializes a qubit hilbert space. Args: N: Number of qubits. graph: (deprecated) a graph from which to extract the number of sites. Examples: Simple spin hilbert space. >>> from netket.hilbert import Qubit >>> hi = Qubit(N=100) >>> print(hi.size) 100 """ N = graph_to_N_depwarn(N=N, graph=graph) super().__init__([0.0, 1.0], N)
def __pow__(self, n): return Qubit(self.size * n) def _mul_sametype_(self, other): assert type(self) == type(other) return Qubit(self.size + other.size)
[docs] def ptrace(self, sites: Union[int, List]) -> Optional["Qubit"]: if isinstance(sites, int): sites = [sites] for site in sites: if site < 0 or site >= self.size: raise ValueError( f"Site {site} not in this hilbert space of site {self.size}" ) Nsites = len(sites) if self.size - Nsites == 0: return None else: return Qubit(N=self.size - Nsites)
def __repr__(self): return "Qubit(N={})".format(self._size) @property def _attrs(self): return (self.size,)