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syntax

  • service_area(F1, F2, dijkstra/traceback)

definition

service_area(F1, F2, dijkstra/traceback) calculates service areas for nodes in the network. A service area is defined as the index number of the nearest desination node for each node in the node set. The results are based on the results of dijkstra calculations. The service_area function requests three arguments:

  1. F1: index numberr of the first node of a link set;
  2. F2index number of the last node of a link set;
  3. dijkstra/traceback: the traceback item, a generated subitem by the dijkstra function.

description

The function results in an index number for the nodes in the nodeset. Use the lookup function to relate these numbers to the origin locations (see example).

applies to

Attributes F1, F2 and dijkstra/traceback with uint32 value type

conditions

The domain of attributes F1 and F2 must match.

since version

5.15

example

attribute<m> dist (NodeSet) := dijkstra(dist, F1, F2, nr_DestNode);
attribute<Destination> servicearea_ns (NodeSet) :=
rlookup(
service_area(
F1
,F2
,dist/TraceBack
)
, nr_DestNode
);
attribute<Destination> servicearea (Origin) := servicearea_ns[nr_OrgNode];
F1 F2
8 7
1 4
16 15
2 3
5 4
6 7
9 10
12 11
14 15
18 20
19 17
3 0
4 11
7 1
10 3
11 13
13 17
15 10
20 21
17 20
domain Linkset, nr of rows = 19

nr_DestNode
14
6
2
19
domain Destination, nr of rows = 5

servicearea
0
1
2
3
1
domain Origin, nr of rows = 5

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