Inheriting From `matplotlib.patches.regularpolygon` Yields `valueerror` On Instantiation

I am trying to derive a class from matplotlib.patches.RegularPolygon. The immediate aim is to have a somewhat unified API for matplotlib.patches.Circle and matplotlib.patches.Regul

Solution 1:

Using

super(matplotlib.patches.RegularPolygon, self).__init__()

you calling the init function of the parent of matplotlib.patches.RegularPolygon. However you would really need to call the init of matplotlib.patches.RegularPolygon itself.

I would also suggest not to use the same name for the subclassed artist, as this might add to confusion here.

Options you have

• Old style

  import matplotlib
  
  classMyRegularPolygon(matplotlib.patches.RegularPolygon):
      def__init__(self, *args, **kwargs):
          matplotlib.patches.RegularPolygon.__init__(self, *args, **kwargs)
  
  r = MyRegularPolygon((0.,0.), 5, radius=5, orientation=0)
  

• New Style (py2 & 3)

  import matplotlib
  
  classMyRegularPolygon(matplotlib.patches.RegularPolygon):
      def__init__(self, *args, **kwargs):
          super(MyRegularPolygon, self).__init__(*args, **kwargs)
  
  r = MyRegularPolygon((0.,0.), 5, radius=5, orientation=0)
  

• New Style (only py3)

  import matplotlib
  
  classMyRegularPolygon(matplotlib.patches.RegularPolygon):
      def__init__(self, *args, **kwargs):
          super().__init__(*args, **kwargs)
  
  r = MyRegularPolygon((0.,0.), 5, radius=5, orientation=0)
  

I would suggest reading What does 'super' do in Python? for some explanation of super.