class_docstr: Generic histogram class for real numbers
  
  Example:
  
      >>> h = Histogram(5)     # Initializing, bin width = 5
      >>> h << [2,3,2,7,8,5,5,0,7,9]     # Adding more items
      >>> print(h)
      N = 10, mean +- sd: 4.8000 +- 2.9740
      [ 0,  5): **** (4)
      [ 5, 10): ****** (6)
docstr: Adds a single number to the histogram.
  
  @param num: the number to be added
  @param repeat: number of repeated additions
docstr_tok: ["Adds","a","single","number","to","the","histogram",".","@","param","num",":","the","number","to","be","added","@","param","repeat",":","number","of","repeated","additions"]
code: def add(self, num, repeat=1):
      """Adds a single number to the histogram.
  
      @param num: the number to be added
      @param repeat: number of repeated additions
      """
      num = float(num)
      binidx = self._get_bin(num, True)
      self._bins[binidx] += repeat
      self._running_mean.add(num, repeat)
  
imports: import math
label_desc: Use image node_id 7 for calling the Histogram obj's underlying member method code with example usage: obj.add(num, repeat) without return types