code: def _inv_nchi_cdf(N, K, alpha):
      """Inverse CDF for the noncentral chi distribution
      See [1]_ p.3 section 2.3"""
      return gammainccinv(N * K, 1 - alpha) / K
  
imports: import numpy
  from scipy.special import gammainccinv
  from scipy.ndimage import convolve
label_desc: Use image node_id 1 for calling a global function with example usage: _inv_nchi_cdf(N, K, alpha) and returns: unknown