class_docstr: A Fourier series field defined on a collocation grid.
class_docstr_tok: ["A","Fourier","series","field","defined","on","a","collocation","grid","."]
docstr: Returns the frequency axis of the grid
docstr_tok: ["Returns","the","frequency","axis","of","the","grid"]
code: def _freq_axis(self):
      r"""Returns the frequency axis of the grid"""
      if self.is_complex:
  
          def f(N, dx):
              return jnp.fft.fftfreq(N, dx) * 2 * jnp.pi
  
      else:
  
          def f(N, dx):
              return jnp.fft.rfftfreq(N, dx) * 2 * jnp.pi
  
      k_axis = [
          f(n, delta) for n, delta in zip(self.domain.N, self.domain.dx)
      ]
      return k_axis
  
imports: import warnings
  from typing import Callable, TypeVar
  import equinox
  from equinox import tree_equal
  from jax import eval_shape
  from jax import numpy
  from jax import vmap
  from jaxtyping import PyTree
  from jaxdf.core import Field
  from jaxdf.geometry import Domain
label_desc: Use image node_id 2 for calling the FourierSeries obj's underlying member method code with example usage: obj._freq_axis() and returns: k_axis, unknown, unknown