Source code for netket.models.jastrow

# Copyright 2021 The NetKet Authors - All rights reserved.

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#    http://www.apache.org/licenses/LICENSE-2.0

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import flax.linen as nn
import jax.numpy as jnp
from jax.nn.initializers import normal

from netket.utils.types import DType, Array, NNInitFunc


[docs]class Jastrow(nn.Module): r""" Jastrow wave function :math:`\Psi(s) = \exp(\sum_{ij} s_i W_{ij} s_j)`. The W matrix is stored as a non-symmetric matrix, and symmetrized during computation by doing :code:`W = W + W.T` in the computation. """ dtype: DType = jnp.complex128 """The dtype of the weights.""" kernel_init: NNInitFunc = normal() """Initializer for the weights.""" @nn.compact def __call__(self, x_in: Array): nv = x_in.shape[-1] dtype = jnp.promote_types(x_in.dtype, self.dtype) x_in = jnp.asarray(x_in, dtype=dtype) kernel = self.param("kernel", self.kernel_init, (nv, nv), self.dtype) kernel = kernel + kernel.T y = jnp.einsum("...i,ij,...j", x_in, kernel, x_in) return y