code: def laplacian(
      x: FiniteDifferences, *, params=None
  ) -> FiniteDifferences:
      r"""Gradient operator for finite differences fields.
  
      Args:
        x: FiniteDifferences field
  
      Returns:
        The gradient of the field
      """
      assert x.dims == 1, "Laplacian only defined for scalar fields"
      new_params = reflection_conv(
          params, x.on_grid[..., 0], reverse=False
      )
      return x.replace_params(new_params)
  
imports: from typing import Union
  import jax
  import numpy
  from jax import numpy
  from jaxdf.conv import fd_coefficients_fornberg, reflection_conv
  from jaxdf.core import operator
  from jaxdf.discretization import Continuous, FiniteDifferences, FourierSeries
label_desc: Use image node_id 18 for calling a global function with example usage: laplacian(x) and returns: x