VISSIM 5.30-05 User Manual

Properties & Options
Simulation of Vehicles and Pedestrians
SIMULATION – MULTIRUN... opens the Multirun window where all additional
settings for the multirun simulation are done.
● Starting random seed:
cf. section 8.1.1 Random
seed.
● Random seed increment:
Offset that will be added
to the random seed for
every subsequent run.
The stochastic variation
is independent of the
size of the number.
When using Dynamic
Assignment this parameter
should be set to 0.
For a multirun simulation with different Starting random seed numbers, the
Random seed increment is decisive. In this case, the particular starting
random seed value which serves as index of the simulation run is attached
to the evaluation file *.LDP.
● Number of runs: Amount of automatic simulation runs to be done.
Depending on the application 5 to 20 runs are recommended. When
using Dynamic Assignment more runs might be necessary.
● Dynamic Assignment Volume Increment (refers only to Dyn. Assignment):
When using Dynamic Assignment the total demand can be
increased successively (similar to command line parameter -v). The start
value is taken from the parameter "Scale total volume to" from the
Dynamic Assignment (cf. section 12.8.6). For every iteration the demand
is increased by this value until 100 % is reached.
Please note, that the start value should not exceed 100% demand.
● Evaluation files directory: Directory where the evaluation and error files
are saved. Press to select a different directory. The flag being added
to the name of the output file by iteration run indicates the actual random
seed value automatically calculated from the start random seed plus the
particular difference resulting from the random seed increment by run.
Since existing files with identical filename are overwritten without
warning, careful selection of the output folder is recommended. As usual,
*.BEW and *.WEG files are saved to the project directory containing the
*.INP file.
● Create archived cost and path files: If this option is active, existing
output files *.BEW and *.WEG stored in the same folder as the *.INP file
will be renamed. Numbers will be added to the filenames prior to creating
new output files. Thus the data file archive allows for subsequent
analyses of changes during Dynamic Assignment. You even might start
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