code: def geocentric_radius(
      geodetic_lat, ell: Ellipsoid = None, deg: bool = True
  ):
      """
      compute geocentric radius at geodetic latitude
  
      https://en.wikipedia.org/wiki/Earth_radius#Geocentric_radius
      """
      geodetic_lat, ell = sanitize(geodetic_lat, ell, deg)
  
      return sqrt(
          (
              (ell.semimajor_axis**2 * cos(geodetic_lat)) ** 2
              + (ell.semiminor_axis**2 * sin(geodetic_lat)) ** 2
          )
          / (
              (ell.semimajor_axis * cos(geodetic_lat)) ** 2
              + (ell.semiminor_axis * sin(geodetic_lat)) ** 2
          )
      )
  
file_path: pymap3d/src/pymap3d/rcurve.py
imports: from __future__ import annotations
  from .ellipsoid import Ellipsoid
  from .mathfun import cos, sin, sqrt
  from .utils import sanitize
label_desc: Use image node_id 1 for calling a global function with example usage: geocentric_radius(geodetic_lat, ell, deg) and returns: sqrt