Pathset config

The pathset_config.xml configuration file corresponds to settings that are related to pathset generation and route-choice.

NOTE: If running MidTerm, this configuration file has only effect when <mid_term_run_mode value="withinday"/>

The root pathset section of the file can be enabled or disabled. If it is set to true, SimMobility will include route-choice in its simulation. Otherwise, the shortest paths available will be chosen.

<pathset enabled = "true">

thread_pool denotes the number of threads that are to be created for generating pathsets. This setting is meaningful only during pathset generation and does not influence anything during withinday simulation runs.

<thread_pool size="7"/>  

The following section corresponds to the configuration settings of pathsets related to private traffic.

<private_pathset enabled="true" mode="normal"> <!--"normal" and "generation" are supported modes -->
    <od_source table="routechoice.pvt_od"/>
    <bulk_generation_output_file name="pvt-pathset.csv" />
    <tables historical_traveltime="supply.link_travel_time" default_traveltime="supply.link_default_travel_time"/>
    <functions pathset_without_banned_area="get_path_set_woba"/>
    <recursive_pathset_generation value="false"/>
    <reroute enabled="false" />
    <utility_parameters>
        <highwayBias value="0.5"/>
    </utility_parameters>
    <path_generators max_segment_speed="26.39"> <!--in m/s--> <!-- 26.39m/s = 95km/hr -->
        <k_shortest_path level="5" />
        <link_elimination types="default,highway" />    <!-- unused for now. Both default and highway are used in the code irrespective of this setting-->
        <random_perturbation modes="time" iterations="100" uniform_range="1,100" /> <!-- for 'modes' attribute, only "time" is supported for now -->
    </path_generators>
</private_pathset>

Similar to enabling or disabling the pathset section, the private_pathset section can also be enabled or disabled. If enabled, route-choice will be performed for private traffic; shortest paths will be taken otherwise. There are two values that are supported for mode attribute. It is set to "normal" for usual withinday simulation runs and it is set to "generation" for generating pathsets. These pathsets are generated for origin destination pairs that are available in the table mentioned in od_source. The pathsets that are generated are produced in an output file that is specified in bulk_generation_output_file. This file is later fetched and the paths are pushed into the database manually. Refer to the [pathset generation] (https://github.com/smart-fm/simmobility-prod/wiki/Pathset-generation) document for more details.

In the tables tag, historical_traveltime contains the [feedback link travel times] (https://github.com/smart-fm/simmobility-prod/wiki/Withinday-feedback-tables#link_travel_time) from previous simulations, whereas default_traveltime contains the default link travel time values. recursive_pathset_generation is enabled when one needs to generate the pathsets to facilitate rerouting. This comes in handy when there is a disruption along his path during the simulation. In such a case, it is a hefty task to generate an alternative path as a part of the simulation. Hence, these alternative path choices from each node of the path to the destination node are generated during pathset generation which makes it easier for an agent to reroute during his simulation. If reroute is enabled, the agents will be allowed to reroute during their simulation in case of any event along his path.

<public_pathset enabled="true" mode="normal"> <!-- "normal" and "generation" modes are supported -->
    <od_source table="routechoice.pt_od"/>
    <bulk_generation_output_file name="pt-pathset.csv" />
    <pathset_generation_algorithms>
        <k_shortest_path level="10" />
        <simulation_approach iterations="100"/>
    </pathset_generation_algorithms>
</public_pathset>

Similar to configuration settings that pertain to private traffic, public_pathset section holds configuration settings that are related to public transit traffic. There are, again, two values that are supported for mode - "normal" and "generation". In generation mode, pathsets are generated for origin destination pairs that are available in the table mentioned in od_source. The pathsets that are generated are produced in an output file that is specified in bulk_generation_output_file. This file is later fetched and the paths are pushed into the database manually. pathset_generation_algorithms holds the parameters that are used in pathset generation for public transit ODs.