Network
A network created in ULTImodel consists of edges and nodes and is extracted from OSM and is
created using network.CreateNetwork.
Edges
Preparation: read TAZ GeoDataFrame
import network.CreateNetwork as CreateNetwork
import geopandas as gpd
taz = gpd.GeoDataFrame.from_file('DK-taz.gpkg')
taz.head()
>>> output
nuts_id cntr_code nuts_name geometry
0 DK011 DK Byen København MULTIPOLYGON (((12.50479 55.63734, 12.48025 55...
1 DK012 DK Københavns omegn MULTIPOLYGON (((12.24627 55.70664, 12.25874 55...
2 DK013 DK Nordsjælland MULTIPOLYGON (((12.24627 55.70664, 12.21994 55...
3 DK014 DK Bornholm MULTIPOLYGON (((14.88943 55.22813, 14.94373 55...
4 DK021 DK Østsjælland MULTIPOLYGON (((12.24627 55.70664, 12.16537 55...
Create network_edges as base for operations, based on taz:
network_edges = CreateNetwork.Edges(country='DK', taz=taz, taz_cn='cntr_code')
From taz, create country polygon(s) for network_edges. If there are islands, the country will
have multiple polygons.
polygons = network_edges.get_polygon(taz_id='nuts_id')
polygons
>>> output
nuts_id cntr_code nuts_name geometry
0 0 DK011 DK Byen København POLYGON ((8.19409 56.72190, 8.18723 56.75394, ...
1 DK011 DK Byen København POLYGON ((14.66314 55.19035, 14.66356 55.19231...
Get edges for selected OSM highway types for the polygons in polygons;
returns number of polygons with edges (not necessarily all polygons in polygons have edges)
n_poly = network_edges.get_edges(filter_highway=["motorway", "trunk", "primary"], polygons=polygons)
n_poly
>>> 2
The edges can be found in network_edges.edges
network_edges.edges.head()
>>> output
highway speed_kph geometry index
0 primary 63.0 LINESTRING (8.75547 55.16922, 8.75502 55.16959... NaN
1 primary 63.0 LINESTRING (8.75547 55.16922, 8.75591 55.16884... NaN
2 primary 80.0 LINESTRING (8.75496 55.31883, 8.75514 55.32270... NaN
3 primary 63.0 LINESTRING (8.75496 55.31883, 8.75013 55.31339... NaN
4 primary 63.0 LINESTRING (8.75496 55.31883, 8.76117 55.32033... NaN
set_attributes creates a unique ID, calculates length and travel time and assigns a type number
network_edges.set_attributes(taz_id='nuts_id', start_id=1)
network_edges.edges.head()
>>> output
highway speed_kph index nuts_id geometry length tt ultimo_id type
0 0 primary 63.0 NaN DK032 LINESTRING (8.75547 55.16922, 8.75502 55.16959... 17.558210 1003.0 1 3
1 0 primary 63.0 NaN DK032 LINESTRING (8.75547 55.16922, 8.75591 55.16884... 7.344446 420.0 2 3
2 0 primary 80.0 NaN DK032 LINESTRING (8.75496 55.31883, 8.75514 55.32270... 2.645051 119.0 3 3
3 0 primary 63.0 NaN DK032 LINESTRING (8.75496 55.31883, 8.75013 55.31339... 17.558210 1003.0 4 3
4 0 primary 63.0 NaN DK032 LINESTRING (8.75496 55.31883, 8.76117 55.32033... 19.593661 1120.0 5 3
Using the nodes created based on the edges (see section Nodes), the start and end node per edge are added and the columns are reduced to the relevant info.
network_edges.set_nodes(nodes, order_col="order", linkid_col="LinkID", nodeid_col="node_id")
network_edges.edges.head()
>>> output
ultimo_id from_node to_node type nuts_id length speed_kph tt geometry
0 1 1246 1245 3 DK032 17.558210 63.0 1003.0 LINESTRING (8.75547 55.16922, 8.75502 55.16959...
1 2 1246 1263 3 DK032 7.344446 63.0 420.0 LINESTRING (8.75547 55.16922, 8.75591 55.16884...
2 3 1245 1248 3 DK032 2.645051 80.0 119.0 LINESTRING (8.75496 55.31883, 8.75514 55.32270...
3 4 1245 1246 3 DK032 17.558210 63.0 1003.0 LINESTRING (8.75496 55.31883, 8.75013 55.31339...
4 5 1245 1399 3 DK032 19.593661 63.0 1120.0 LINESTRING (8.75496 55.31883, 8.76117 55.32033...
Connect subgraphs in the network (isolated networks) and remove isolated edges and nodes
to ensure that the edges are routable with connect_subgraphs. The input is either
network_edges.edges or a separate GeoDataFrame with edges and unique network nodes
nodes_unique.
final_network, final_nodes = network_edges.connect_subgraphs(nodes=nodes_unique)
>>> Connecting 8 sub graphs...
print(len(network_edges.edges), len(final_network))
final_network.head()
>>> output
3550 3538
ultimo_id from_node to_node type nuts_id length speed_kph tt geometry
0 1 1246 1245 3 DK032 17.558210 63.0 1003.0 LINESTRING (8.75547 55.16922, 8.75502 55.16959...
1 2 1246 1263 3 DK032 7.344446 63.0 420.0 LINESTRING (8.75547 55.16922, 8.75591 55.16884...
2 3 1245 1248 3 DK032 2.645051 80.0 119.0 LINESTRING (8.75496 55.31883, 8.75514 55.32270...
3 4 1245 1246 3 DK032 17.558210 63.0 1003.0 LINESTRING (8.75496 55.31883, 8.75013 55.31339...
4 5 1245 1399 3 DK032 19.593661 63.0 1120.0 LINESTRING (8.75496 55.31883, 8.76117 55.32033...
print(len(nodes_unique), len(final_nodes))
final_nodes.head()
>>> output
node_id num_links geometry
0 1 2 POINT (10.00132 55.71526)
1 2 2 POINT (10.00162 55.42639)
2 3 2 POINT (10.00209 56.44808)
3 4 2 POINT (10.00478 56.44625)
4 5 2 POINT (10.00589 57.50701)
Nodes
The class Nodes in CreateNetwork creates Nodes at the ends of each edge. Using a
GeoDataFrame edges (can be created with Edges), the network_nodes instance is created.
import network.CreateNetwork as CreateNetwork
import geopandas as gpd
edges = gpd.GeoDataFrame.from_file('edges.gpkg')
edges.head()
>>> output
highway speed_kph index nuts_id geometry length tt ultimo_id type
0 0 primary 63.0 NaN DK032 LINESTRING (8.75547 55.16922, 8.75502 55.16959... 17.558210 1003.0 1 3
1 0 primary 63.0 NaN DK032 LINESTRING (8.75547 55.16922, 8.75591 55.16884... 7.344446 420.0 2 3
2 0 primary 80.0 NaN DK032 LINESTRING (8.75496 55.31883, 8.75514 55.32270... 2.645051 119.0 3 3
3 0 primary 63.0 NaN DK032 LINESTRING (8.75496 55.31883, 8.75013 55.31339... 17.558210 1003.0 4 3
4 0 primary 63.0 NaN DK032 LINESTRING (8.75496 55.31883, 8.76117 55.32033... 19.593661 1120.0 5 3
network_nodes = CreateNetwork.Nodes(edges=edges)
The initial node geometries are created with create_nodes, resulting in a GeoDataFrame
with the edge ID and position of the node (order, start or destination).
network_nodes.create_nodes(id_col="ultimo_id", geom_col="geometry")
network_nodes.nodes.head()
>>> output
LinkID order geometry
0 1 0 POINT (8.75547 55.16922)
1 1 1 POINT (8.75496 55.31883)
2 2 0 POINT (8.75547 55.16922)
3 2 1 POINT (8.81108 55.11278)
4 3 0 POINT (8.75496 55.31883)
To remove duplicates, the coordinates of all the start and end nodes are compared in
remove_duplicates and a GeoDataFrame with all unique nodes is produced.
network_nodes.remove_duplicates()
network_nodes.nodes_unique.head()
>>> output
xy num_links geometry
0 [(10.001318200000002, 55.715256698015416)] 2 POINT (10.00132 55.71526)
1 [(10.001617600000001, 55.42638559797401)] 2 POINT (10.00162 55.42639)
2 [(10.002085100000008, 56.44808009811454)] 2 POINT (10.00209 56.44808)
3 [(10.004784400000002, 56.446253498114366)] 2 POINT (10.00478 56.44625)
4 [(10.005892199999995, 57.50701369824364)] 2 POINT (10.00589 57.50701)
Based on these unique nodes, IDs are created in set_node_id.
network_nodes.set_node_id(id_col='node_id', start=1)
network_nodes.nodes_unique.head()
>>> output
node_id num_links geometry
0 1 2 POINT (10.00132 55.71526)
1 2 2 POINT (10.00162 55.42639)
2 3 2 POINT (10.00209 56.44808)
3 4 2 POINT (10.00478 56.44625)
4 5 2 POINT (10.00589 57.50701)
---
network_nodes.nodes.head()
>>> output
node_id LinkID order geometry
0 1246 1 0 POINT (8.75547 55.16922)
1 1245 1 1 POINT (8.75496 55.31883)
2 1246 2 0 POINT (8.75547 55.16922)
3 1263 2 1 POINT (8.81108 55.11278)
4 1245 3 0 POINT (8.75496 55.31883)
Connectors
Preparation: read TAZ GeoDataFrame and population GeoDataFrame
import network.CreateNetwork as CreateNetwork
import geopandas as gpd
taz = gpd.GeoDataFrame.from_file('DK-taz.gpkg')
taz.head()
>>> output
nuts_id cntr_code nuts_name geometry
0 DK011 DK Byen København MULTIPOLYGON (((12.50479 55.63734, 12.48025 55...
1 DK012 DK Københavns omegn MULTIPOLYGON (((12.24627 55.70664, 12.25874 55...
2 DK013 DK Nordsjælland MULTIPOLYGON (((12.24627 55.70664, 12.21994 55...
3 DK014 DK Bornholm MULTIPOLYGON (((14.88943 55.22813, 14.94373 55...
4 DK021 DK Østsjælland MULTIPOLYGON (((12.24627 55.70664, 12.16537 55...
# read population
pop = gpd.GeoDataFrame.from_file('4326-points-population.gpkg')
pop.head()
>>> output
VALUE cntr_code geometry
0 0.000000 DK POINT (12.52891 55.58360)
1 0.063969 DK POINT (12.53872 55.58360)
2 0.063969 DK POINT (12.54852 55.58360)
3 0.000000 DK POINT (12.55832 55.58360)
4 1152.648 DK POINT (12.56812 55.58360)
Initialize the connector class with
conn_ = CreateNetwork.Connectors()
Determine population centers
conn_.find_connector_locations(taz, pop, taz_geom='geometry')
conn_.connectors.head()
>>> output
nuts_id c_n weight geometry
0 DK011 0 0.000048 POINT (12.76171 55.63546)
1 DK011 1 0.785301 POINT (12.53487 55.68012)
2 DK011 2 0.214651 POINT (12.60310 55.61478)
0 DK012 3 0.493351 POINT (12.39750 55.67478)
1 DK012 4 0.103410 POINT (12.24445 55.65573)
Move population centers to network nodes
nodes = gpd.GeoDataFrame.from_file('unique-nodes.gpkg')
# add country code to nodes
nodes['cntr_code'] = 'DK'
>>> output
node_id num_links geometry
0 1 2 POINT (10.00132 55.71526)
1 2 2 POINT (10.00162 55.42639)
2 3 2 POINT (10.00209 56.44808)
3 4 2 POINT (10.00478 56.44625)
4 5 2 POINT (10.00589 57.50701)
all_conn = conn_.identify_connector_nodes(nodes=nodes, zone='nuts_id', weight="weight", country_check='cntr_code')
all_conn.head()
>>> output
No duplicates detected!
node_id geometry nuts_id c_n weight
0 1095 POINT (12.74977 55.60094) DK011 0 0.000048
1 1014 POINT (12.51936 55.70192) DK011 1 0.785301
2 1078 POINT (12.60314 55.62947) DK011 2 0.214651
3 890 POINT (12.39536 55.67467) DK012 3 0.493351
4 777 POINT (12.23742 55.65711) DK012 4 0.103410
