def delete_colormap(self, name=None):
        """
        Deletes the colormap with the specified name. None means use the internal
        name (see get_name())
        """
        if name == None: name = self.get_name()
        if name == "" or not type(name)==str: return "Error: invalid name."

        # assemble the path to the colormap
        path = _os.path.join(_settings.path_home, 'colormaps', name+".cmap")
        _os.unlink(path)

        return self