Exemple #1
0
def get_multimodal(inData, params, request, plot=True):
    o = request.origin
    d = request.destination
    params.GTFS.beta = 5

    # A find transfer stop from ride to transit
    # get two distances
    leg1 = inData.skims.ride.loc[inData.transit_stops.node][
        o]  # from origin to all transit_stops via road network
    leg2 = inData.skims.transit.loc[d][
        inData.transit_stops.
        node] / params.GTFS.beta  # and from all transit_stop to destination with transit

    multimodalRT = pd.concat(
        [leg1, leg2],
        axis=1)  # merge them by the stop_point (two columns of travel times)
    multimodalRT['time'] = multimodalRT.sum(axis=1) +\
                           params.GTFS.transfer_penalty  # calculate sum of travel times plus transfer penalty
    transfer_pointRT = multimodalRT.time.idxmin(
    )  # find stop of minimal total time - this is transfer point

    # B find transfer stop from transit to ride
    leg1 = inData.skims.transit.loc[inData.transit_stops.node][
        o] / params.GTFS.beta  # transit distances from origin to stop points
    leg2 = inData.skims.ride.loc[d][
        inData.transit_stops.
        node]  # ride distances from transit stops to destination

    multimodalTR = pd.concat([leg1, leg2],
                             axis=1)  # merge to two-clumn data frame
    multimodalTR['time'] = multimodalTR.sum(
        axis=1) + params.GTFS.transfer_penalty  # calc total travel and penalty
    transfer_pointTR = multimodalTR.time.idxmin(
    )  # find transfer point of minimal time

    if plot:
        import seaborn as sns
        dists = DotMap()
        G = inData.GTFS.G
        palette = sns.color_palette("bright")
        ev = [
            0.001 if 'IVT' in edge[-1].keys() else 0.3
            for edge in G.edges(data=True)
        ]  # assign line weights
        colors = [
            'blue' if 'IVT' in edge[-1].keys() else 'grey'
            for edge in G.edges(data=True)
        ]  # assign color

        #plot graph
        fig, ax = ox.plot_graph(G,
                                fig_height=15,
                                fig_width=15,
                                node_size=0,
                                edge_linewidth=ev,
                                show=False,
                                close=False,
                                edge_color=colors)
        # plot stops
        ax.scatter(inData.transit_stops.x,
                   inData.transit_stops.y,
                   s=3,
                   c='black',
                   marker='x')
        # plot O and D
        ax.annotate(
            'O',
            (inData.nodes.loc[o].x * 1.0002, inData.nodes.loc[o].y * 1.00001))
        ax.annotate(
            'D',
            (inData.nodes.loc[d].x * 1.0002, inData.nodes.loc[d].y * 1.00001))
        # plot two transfer points
        TRp = inData.transit_stops[inData.transit_stops.node ==
                                   transfer_pointTR].squeeze()
        ax.scatter(TRp.x, TRp.y, s=30, c='brown', marker='o')
        ax.annotate('T->R', (TRp.x * 1.0002, TRp.y * 1.00001))
        TRp = inData.transit_stops[inData.transit_stops.node ==
                                   transfer_pointRT].squeeze()
        ax.scatter(TRp.x, TRp.y, s=30, c='green', marker='o')
        ax.annotate('R->T', (TRp.x * 1.0002, TRp.y * 1.00001))

        route = nx.shortest_path(G, o, d, weight='TRANSIT_COST')
        dists.transit = nx.shortest_path_length(
            G, o, d, weight='TRANSIT_COST') / params.GTFS.beta

        ax = add_route(G, ax, route, color='black', alpha=0.7, key='length')
        route = nx.shortest_path(G, o, d, weight='length')
        dists.ride = nx.shortest_path_length(
            G, o, d, weight='length') / params.speeds.ride
        ax = add_route(G, ax, route, color='blue', alpha=0.7, key='length')

        route = nx.shortest_path(G, o, transfer_pointRT, weight='length')
        ax = add_route(G, ax, route, color='green', alpha=0.7, key='length')
        route = nx.shortest_path(G, transfer_pointRT, d, weight='TRANSIT_COST')
        ax = add_route(G, ax, route, color='green', alpha=0.7, key='length')

        dists.RT_R = nx.shortest_path_length(
            G, o, transfer_pointRT, weight='length') / params.speeds.ride
        dists.RT_T = nx.shortest_path_length(
            G, transfer_pointRT, d, weight='TRANSIT_COST') / params.GTFS.beta
        dists.RT = dists.RT_R + dists.RT_T

        route = nx.shortest_path(G, o, transfer_pointTR, weight='TRANSIT_COST')
        ax = add_route(G, ax, route, color='brown', alpha=0.7, key='length')
        route = nx.shortest_path(G, transfer_pointTR, d, weight='length')
        ax = add_route(G, ax, route, color='brown', alpha=0.7, key='length')

        dists.TR_T = nx.shortest_path_length(
            G, o, transfer_pointTR, weight='TRANSIT_COST') / params.GTFS.beta
        dists.TR_R = nx.shortest_path_length(
            G, transfer_pointTR, d, weight='length') / params.speeds.ride
        dists.TR = dists.TR_R + dists.TR_T

        return pd.Series(dists).to_frame().drop(['_typ', '_subtyp'])