Generic parameters allow an arbitrary mapping of string keys to string values. They can be used for user-defined data storage but some key/value pairs also affect the simulation.
The following objects support the definition of custom parameters in their XML definitions:
Parameters support the following functionality
- editing in netedit
- Supplying additional information to the user (via sumo-gui dialogs, text annotations or when inspecting XML files)
- reading and writing via TraCI.
- retaining custom information when saving and loading simulation state
Some parameters are special and affect (or reflect) simulation behavior in the following ways:
- setting up devices on a per-vehicle basis
- customizing the functionality of actuated traffic lights
- configuring vehicle types for use with the electric vehicle model
- tracking the public transport 'tripId' that may change at stops.
- setting transient junction model parameters
- customizing parking search traffic (cruising for parking)
- configuring parameters of carFollowModels via TraCI
- retrieving parameters of carFollowModels via TraCI
- configuring device parameters via TraCI
- retrieving device parameters via TraCI (some devices have read-only parameters)
Parameters are always defined as child elements of the respective object:
<vehicle id="v0" route="route0" depart="0"> <param key="answer to everything" value="42"/> </vehicle>