code: def _circular_mean(x):
      """Compute mean of circular variable measured in radians.
  
      The result is between -pi and pi.
      """
      sinr = np.sum(np.sin(x))
      cosr = np.sum(np.cos(x))
      mean = np.arctan2(sinr, cosr)
  
      return mean
  
imports: import warnings
  import numpy
  from scipy.fftpack import fft
  from scipy.optimize import brentq
  from scipy.signal import convolve, convolve2d, gaussian
  from scipy.sparse import coo_matrix
  from scipy.special import ive
  from ..utils import _cov, _dot, _stack, conditional_jit
label_desc: Use image node_id 23 for calling a global function with example usage: _circular_mean(x) and returns: mean