Plotting domain diagrams - a ring around the residue name and id and chain id. The colors are
        determined by the chain id and are extracted from matplotlib colormap "terrain" (ver. "09.2016")
        The plot is saved as svg file with residue id and chain id as filename for more certain
        identification.

def plot_domain_diagrams(self):
        """
        Plotting domain diagrams - a ring around the residue name and id and chain id. The colors are
        determined by the chain id and are extracted from matplotlib colormap "terrain" (ver. "09.2016")
        The plot is saved as svg file with residue id and chain id as filename for more certain
        identification.
        """
        # width of the circle around plot
        width=0.20


        # define color library
        cmap = plt.get_cmap('terrain')
        colors = [cmap(i) for i in numpy.linspace(0, 0.75, len(self.topology_data.universe.protein.segments))]
        domain_colors = {seg:colors[i] for i,seg in enumerate(self.topology_data.universe.protein.segments.segids.tolist())}
        for res in self.topology_data.dict_of_plotted_res:
            color = [domain_colors[res[2]],'white']
            #color = [self.colors_amino_acids[self.amino_acids[res.resname]],'white']
            plt.figure(figsize=(2.5,2.5))
            ring1,_=plt.pie([1],  radius=1-width, startangle=90, colors=color, counterclock=False)
            plt.axis('equal')
            plt.setp(ring1, width=width, edgecolor='white')
            if len(self.topology_data.universe.protein.segments)<=1:
                #Parameters for amino diagrams without segids
                plt.text(0,-0.4,res[0]+"\n"+res[1],ha='center',size=36, fontweight="bold")
            else:
                #Parameters for amino diagrams with segids
                plt.text(0,-0.22,res[0]+"\n"+res[1]+"\n"+res[2],ha='center',size=28, fontweight="bold")
            #play with the dpi
            pylab.savefig(res[1]+res[2]+".svg", dpi=300, transparent=True)