Calculates the geodesic distance betweeen two vertices using Dijkstra's
        algorithm.

        Parameters
        ----------
        start_vertex : int
            Vertex index indicating the start point of the geodesic segment.

        end_vertex : int
            Vertex index indicating the end point of the geodesic segment.

        Returns
        -------
        length : float
            Length of the geodesic segment.

def geodesic_distance(self, start_vertex, end_vertex):
        """
        Calculates the geodesic distance betweeen two vertices using Dijkstra's
        algorithm.

        Parameters
        ----------
        start_vertex : int
            Vertex index indicating the start point of the geodesic segment.

        end_vertex : int
            Vertex index indicating the end point of the geodesic segment.

        Returns
        -------
        length : float
            Length of the geodesic segment.

        """
        length = self.geodesic(start_vertex, end_vertex).GetLength()
        return length