def _draw_background(self, divisions=10):
        """
        Draws the background of the dial

        :param divisions: the number of divisions
        between 'ticks' shown on the dial
        :return: None
        """
        self.canvas.create_arc(2, 2, self.size-2, self.size-2,
                               style=tk.PIESLICE, start=-60, extent=30,
                               fill='red')
        self.canvas.create_arc(2, 2, self.size-2, self.size-2,
                               style=tk.PIESLICE, start=-30, extent=60,
                               fill='yellow')
        self.canvas.create_arc(2, 2, self.size-2, self.size-2,
                               style=tk.PIESLICE, start=30, extent=210,
                               fill='green')

        # find the distance between the center and the inner tick radius
        inner_tick_radius = int(self.size * 0.4)
        outer_tick_radius = int(self.size * 0.5)

        for tick in range(divisions):
            angle_in_radians = (2.0 * cmath.pi / 3.0) \
                               + tick/divisions * (5.0 * cmath.pi / 3.0)
            inner_point = cmath.rect(inner_tick_radius, angle_in_radians)
            outer_point = cmath.rect(outer_tick_radius, angle_in_radians)

            self.canvas.create_line(
                *self.to_absolute(inner_point.real, inner_point.imag),
                *self.to_absolute(outer_point.real, outer_point.imag),
                width=1
            )
def _draw_background ( self , divisions = 10 ) : self . canvas . create_arc ( 2 , 2 , self . size - 2 , self . size - 2 , style = tk . PIESLICE , start = - 60 , extent = 30 , fill = 'red' ) self . canvas . create_arc ( 2 , 2 , self . size - 2 , self . size - 2 , style = tk . PIESLICE , start = - 30 , extent = 60 , fill = 'yellow' ) self . canvas . create_arc ( 2 , 2 , self . size - 2 , self . size - 2 , style = tk . PIESLICE , start = 30 , extent = 210 , fill = 'green' ) inner_tick_radius = int ( self . size * 0.4 ) outer_tick_radius = int ( self . size * 0.5 ) for tick in range ( divisions ) : angle_in_radians = ( 2.0 * cmath . pi / 3.0 ) + tick / divisions * ( 5.0 * cmath . pi / 3.0 ) inner_point = cmath . rect ( inner_tick_radius , angle_in_radians ) outer_point = cmath . rect ( outer_tick_radius , angle_in_radians ) self . canvas . create_line ( * self . to_absolute ( inner_point . real , inner_point . imag ) , * self . to_absolute ( outer_point . real , outer_point . imag ) , width = 1 )
Draws the background of the dial

        :param divisions: the number of divisions
        between 'ticks' shown on the dial
        :return: None