nkDSL 0.1.1a0

Symbolic operator DSL for NetKet discrete JAX operators

nkDSL

nkDSL is a standalone extraction of the symbolic operator DSL from neuraLQX. It provides a compact, declarative way to define discrete operators in NetKet and compile them into executable JAX-backed operator kernels.

[!WARNING] nkDSL is currently experimental (alpha) and not a production release. We are still testing and refining core behavior, interfaces, and performance. Expect API changes between releases while the package matures.

What it does

With nkDSL, you describe an operator in terms of

• where to iterate, such as sites, pairs, or user-defined index sets,
• when a branch is active, through symbolic predicates,
• how to rewrite a configuration, through update programs,
• what matrix element to assign to each emitted branch.

The result is a symbolic operator that can be compiled into a NetKet-compatible executable operator.

Example: 1D transverse-field Ising model

The example below builds $H = -J \sum_{\langle i,j \rangle} \sigma_i^z \sigma_j^z - h \sum_i \sigma_i^x$ for a periodic chain. The diagonal Ising interaction is emitted with an identity update, while the transverse-field term flips one spin at a time.

import netket as nk
from nkdsl import SymbolicDiscreteJaxOperator, site, write

L = 8
J = 1.0
h = 0.5

hilbert = nk.hilbert.Spin(s=0.5, N=L)
graph = nk.graph.Chain(length=L, pbc=True)

ising = (
    SymbolicDiscreteJaxOperator(hilbert, "ising_tfim", hermitian=True)
    .for_each(("i", "j"), over=graph.edges())
    .emit(
        matrix_element=1.2 * site("i").value * site("j").value,
    )
    .for_each_site("i")
    .emit(
        write("i", -site("i").value),
        matrix_element=-0.7,
    )
    .compile()
)

# now, `ising` is a NetKet DiscreteJaxOperator subclass, and can be used in NetKet

Installation

Install directly from PyPI:

python -m pip install --upgrade pip
python -m pip install nkdsl

Status

nkdsl is currently a small, focused package for the recent DSL operator work developed in neuraLQX. Right now the goal is clarity and usability rather than a broad, frozen API surface.

License

This project is licensed under Apache License 2.0. See LICENSE for the full text.