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 or the elements of an iterable to the histogram.
  
  @param data: the data to be added
docstr_tok: ["Adds","a","single","number","or","the","elements","of","an","iterable","to","the","histogram",".","@","param","data",":","the","data","to","be","added"]
code: def add_many(self, data):
      """Adds a single number or the elements of an iterable to the histogram.
  
      @param data: the data to be added"""
      try:
          iterator = iter(data)
      except TypeError:
          iterator = iter([data])
      for x in iterator:
          self.add(x)
  
imports: import math
label_desc: Use image node_id 8 for calling the Histogram obj's underlying member method code with example usage: obj.add_many(data) without return types