code: def r2z(r):
      
      with np.errstate(invalid='ignore', divide='ignore'):
          return 0.5 * (np.log(1 + r) - np.log(1 - r))
docs: Function that calculates the Fisher z-transformation
  
      Parameters
      ----------
      r : int or ndarray
          Correlation value
  
      Returns
      ----------
      result : int or ndarray
          Fishers z transformed correlation value