code: def circstd(samples, high=2 * pi, low=0, axis=None):
      """
      Compute the circular standard deviation for samples assumed to be in the
      range [low to high].
  
      Parameters
      ----------
      samples : array_like
          Input array.
      low : float or int, optional
          Low boundary for circular standard deviation range.  Default is 0.
      high : float or int, optional
          High boundary for circular standard deviation range.
          Default is ``2*pi``.
      axis : int, optional
          Axis along which standard deviations are computed.  The default is
          to compute the standard deviation of the flattened array.
  
      Returns
      -------
      circstd : float
          Circular standard deviation.
  
      Notes
      -----
      This uses a definition of circular standard deviation that in the limit of
      small angles returns a number close to the 'linear' standard deviation.
  
      Examples
      --------
      >>> from scipy.stats import circstd
      >>> circstd([0, 0.1*np.pi/2, 0.001*np.pi, 0.03*np.pi/2])
      0.063564063306
  
      """
      samples, ang = _circfuncs_common(samples, high, low)
      S = sin(ang).mean(axis=axis)
      C = cos(ang).mean(axis=axis)
      R = hypot(S, C)
      return ((high - low) / 2.0 / pi) * sqrt(-2 * log(R))
  
imports: from __future__ import division, print_function, absolute_import
  import math
  import warnings
  from collections import namedtuple
  import numpy
  from numpy import isscalar, r_, log, around, unique, asarray, zeros, arange, sort, amin, amax, any, atleast_1d, sqrt, ceil, floor, array, compress, pi, exp, ravel, count_nonzero, sin, cos, arctan2, hypot
  from scipy._lib.six import string_types
  from scipy import optimize
  from scipy import special
  from .None import statlib
  from .None import stats
  from .stats import find_repeats, _contains_nan
  from .contingency import chi2_contingency
  from .None import distributions
  from ._distn_infrastructure import rv_generic
label_desc: Use image node_id 39 for calling a global function with example usage: circstd(samples, high, low, axis) and returns: unknown