---
title: District
---

## districts2poly.py

Transform
[districts](../Demand/Importing_O/D_Matrices.md#describing_the_taz)
into polygons for visualization in [sumo-gui](../sumo-gui.md).
Using the options **--hue, --saturation, --brightness** the colors can be controlled. Each of these options
supports values from \[0, 1\] as well as the special value *random*.

```
python tools/districts2poly.py <net-file> <route-file>
```

!!! caution
    Only districts using the attribute `edges` are currently supported

## edgesInDistricts.py

Parses a network and a list of polygons and writes a taz file with all the edges which are inside the respective polygonal shape.
The taz-shape-files must be in the format generated by
[polyconvert](../polyconvert.md).

```
python tools/edgesInDistricts.py -n <net-file> -t <taz-files>
```


Call option **--help** for additional details.

!!! caution
    The provided taz shapes must use the same coordinate projection as the network file. The best way to ensure this when importing shapes with [polyconvert](../polyconvert.md) is by setting option **--net-file**

## filterDistricts.py

Filter a taz (district) file using a network file and a vehicle class so
that only edges which allow the given vehicle class are included in the
taz definitions.

```
python tools/district/filterDistricts.py -n <net-file> -t <taz-file> -o <output-file> --vclass passenger
```

Call option **--help** for additional details.

## generateBidiDistricts.py

Finds edges that are opposites of each other and puts them in a common
district (TAZ). This can be used to improve routing in conjunction with
[trip attributes fromTaz and
toTaz](../Definition_of_Vehicles,_Vehicle_Types,_and_Routes.md#traffic_assignment_zones_taz).

```
python tools/generateBidiDistricts.py <net-file>
```

Call option **--help** for additional details.

### Example usage

When applied to a typical OSM network, and edge and the edge with the
negated id describe opposite direction edges of the same road. The
generated bidi-taz would look like this:

```xml
<taz id="-123" edges="-123 123"/>
<taz id="123" edges="-123 123"/>
```

The `<trip>` definitions that would typically use attributes *from* and *to*
instead use the attributes *fromTaz* and *toTaz*:

```xml
<trip id="someTrip" from="123" to="456" depart="0"/>
<trip id="someTripWithBidiTaz" fromTaz="123" toTaz="456"/>
```

The second definition would allow departure from either edge *123*' or
*-123* **due to the way the taz *123* ** is defined. This can prevent
unwanted turn-arounds and the beginning and end of generated trips and
thus simplifies trips created from mapping of geo-coordinates.


## gridDistricts.py

Generates a grid of districts (TAZ) with a given width (in m) for a given network file.

```
python tools/district/gridDistricts.py -n <net-file> -o <output-file> -w 300
```


## stationDistricts.py

Segment a public transport network based on nearby stations.
A station is defined by all stops (`<busStop>` or `<trainStop>`) that have the same `name` attribute. Each edge that belongs to the public transport network for a configurable list of vClasses is assigned to the nearest station. Each station is then written as a `<taz>` with its assigned edges.
By default only edges that permit vehicle classes `rail` or `rail_urban` are considered (can be set via option **--vclasses**)
The following edges are considered part of the public transport network:

- a) edges that have a stop
- b) edges within a configurable radius around a station
- c) edges that are connected to edges of category a) or b)

If there are multiple stops with different names (stations) on the same edge, the following behaviors are possible:

- **default**: the edge belongs to multiple stations (`<taz>`)
- option **--merge**: the stations are merged into a joint station with `name="<NAME1>|<NAME2>"`
- option **--split-output**: a patch file with splits is written that allows further processing of the input network. After splitting the net and running **stationDistricts.py** again, each stop will have its own edge

Example call:

```
python tools/district/stationDistricts.py -n <net-file> -s <stop-file> -o <output-file>
```

## tazRel2POI.py

Load a TAZ (district) file together with a [tazRelation file](../Demand/Importing_O/D_Matrices.md#tazrelation_format) and generate a [POI](../Simulation/Shapes.md) for each TAZ.
The size of the POI is used to indicate aggregated statistics about incoming/outgoing/all tazRelations.

Example call:

```
python tools/district/tazRel2POI.py --taz-file <taz-file> --taz-relation-file <taz-relation-file> -o <output-file>
```

Further Options

- **--size-metric**: select the value that shall be visualized by the POI size ('in', 'out', or 'all'). Default is 'all'
- **--attribute**: select the tazRelation attribute to visualize (default 'count')

!!! note
    By default, the statistic is directly used as poi diameter in m. The visual scaling can be adjusted in the sumo-gui settings with *poi exaggeration*.

!!! note
    By default, POIs are not shown in netedit data-mode (F4). If they should be shown together with the tazRelations, netedit data-mode visualization option *show shapes* (<kbd>Alt+3</kbd>) must be active
