Network functions

Network functions are used to build and calculate with network topologies like connect or impedance

These pages document what each function does and how to call it. For the methods they implement, such as how to choose an accessibility indicator, which network data to start from and how to connect origins and destinations to a network, see the Accessibility Modelling wiki.

• first_node - a point data item with the coordinates of the first point of an arc or polygon
• last_node - a point data item with the coordinates of the last point of an arc or polygon

• connect - creates the nearest point on an arc/polygon data item from a point data item or finds the nearest point in a point data item from another point data item. Includes an optional maximum geographic search radius
• connect_eq - creates the nearest point on an arc/polygon data item from a point data item if the values of two data items match
• connect_ne - creates the nearest point on an arc/polygon data item from a point data item if the values of two data items do not match
• connect_neighbour - a relation to the nearest point in the same point data item, not being the point itself
• connect_info - information for each point on the connection to an arc/polygon data item, as made by the connect function
• connect_info_eq - information for each point on the connection to an arc/polygon data item, as made by the connect_eq function
• connect_info_ne - information for each point on the connection to an arc/polygon data item, as made by the connect_ne function
• dist_info - variant of connect_info to only show the distance between arc/polygon data item and points
• connected_parts - the connected (sub)networks that exist in a set of links
• strongly_connected_components - identifies strongly connected components in a directed graph
• capacitated_connect - finds the nearest point in a point data item from another point data item with a capacity constraint

• Impedance general - a description of the dijkstra algorithm
• Impedance key entities - a description on nodes and links
• Impedance functions - how to apply the impedance function
• Impedance options - optional parameters of the impedance function
• Impedance warning - warning if the impedance is applied with very large datasets
• Impedance interaction potential - additional information on the concept of interaction potential
• Impedance additional - some additional information on impedance functions
• Impedance future - our ideas on potential future impedance functionality
• Impedance links - interesting links
• Impedance example origin to nearest destination - an example of how to apply the impedance function to calculate the distances of a point set to the nearest point in another point set

• Impedance obsolete dijkstra
• Impedance obsolete dijkstra OD
• Impedance obsolete dijkstra directed

• trace_back - the amount of flow for each link in the network.
• service_area - the relation to the nearest destination node for each node in the node set.