starling_sim.basemodel.topology.topology

Module Contents

Classes

Topology

This abstract class describes a network of the simulation.

Attributes

NETWORK_WEIGHT_CLASSES

starling_sim.basemodel.topology.topology.NETWORK_WEIGHT_CLASSES
class starling_sim.basemodel.topology.topology.Topology(transport_mode, weight_class=None, store_paths=False)

Bases: abc.ABC

This abstract class describes a network of the simulation.

Networks are stored as NetworkX graphs.

TIME_ATTRIBUTE = 'time'
LENGTH_ATTRIBUTE = 'length'
init_weight(weight_class)

Initialise the weight class.

Parameters:

weight_class – weight class key

setup()

Prepare the topology for the simulation run.

Initialise the network graph, set relevant attributes and compute weight values for path evaluation.

abstract init_graph()

Initialise the network graph from any data source.

abstract add_time_and_length(u, v, d)

Set the TIME_ATTRIBUTE and LENGTH_ATTRIBUTE attributes on the graph edge.

Parameters:

  • u – edge origin

  • v – edge destination

  • d – edge data

compute_weights(u, v, d)

For each edge, set a value for each weight hash.

Parameters:

  • u –

  • v –

  • d –

shortest_path_length(origin, destination, parameters)
dijkstra_shortest_path_and_length(origin, destination, parameters, return_weight=False)

Find the path from origin to destination with minimum the total weight.

Get the hash corresponding to the parameters and call Dijkstra’s algorithm on the corresponding weight values.

Raises an exception if origin or destination is None, instead of computing all shortest path (which is what NetworkX would do)

Parameters:

  • origin – origin position

  • destination – destination position

  • parameters – parameters defining the utility

  • return_weight – also return the total weight

Returns:

path (list of positions), duration, length

compute_dijkstra_path(origin, destination, weight)
evaluate_path_duration_and_length(path)
get_positions()

Return the list of all topology positions

Returns:

list of positions

get_edge_data(node1, node2, data)

Return the corresponding edge information

Parameters:

  • node1 – node of the topology

  • node2 – node of the topology

  • data – requested attribute

Returns:

data information of the edge

abstract position_localisation(position)

Return the localisation [lat, lon] of the position

Parameters:

position – position in the topology

Returns:

list [lat, lon]

abstract nearest_position(localisation)

Return the nearest position to given localisation (lat, lon)

Parameters:

localisation – (lat, lon) tuple

Returns:

position

abstract localisations_nearest_nodes(x_coordinates, y_coordinates, return_dist=False)

Return the graph nodes nearest to a list of points.

This method should allow a faster computation than multiple nearest_position calls.

Parameters:

  • x_coordinates – list of X coordinates of the localisations (lon in GPS)

  • y_coordinates – list of Y coordinates of the localisations (lat in GPS)

  • return_dist – optionally also return distance between points and nearest nodes

Returns:

list of nearest nodes