original_docstring: Return the population standard deviation of a float list.
docstring: Return the population standard deviation of a float list.
docstring_tokens: Return the population standard deviation of a float list .
code: def pstdev(lst):
      """Return the population standard deviation of a float list."""
      if len(lst) == 0:
          return None
      else:
          mean_squares = sum(list(map(lambda x: x**2, lst)))/float(len(lst))
          square_mean = (sum(lst)/float(len(lst)))**2
          return math.sqrt(float(mean_squares) - (square_mean))
code_tokens: def pstdev ( lst ) : if len ( lst ) == 0 : return None else : mean_squares = sum ( list ( map ( lambda x : x ** 2 , lst ) ) ) / float ( len ( lst ) ) square_mean = ( sum ( lst ) / float ( len ( lst ) ) ) ** 2 return math . sqrt ( float ( mean_squares ) - ( square_mean ) )
short_docstring: Return the population standard deviation of a float list.
short_docstring_tokens: Return the population standard deviation of a float list .
comment: """Return the population standard deviation of a float list."""