Research
Converting Shape Files for use with Paramics
A cost share project funded by the California Department of Transportation (Caltrans)
Project Summary
Traffic microsimulation modeling software such as Quadstone’s Paramics®
has considerable potential in improving transportation planning, operations
and emergency management. However it requires extremely detailed data on
road geometry, structure (number of lanes), speed limits, etc, as well as
demand and trip generation. The potential of these tools is limited by the
availability and quality of the input data, and this is currently a real
impediment to the widespread use and benefit of microsimulation.
In many cases the requisite data do exist in various DOT offices. Road geometry is traditionally created and stored in computer-assisted drafting
(CAD) files with local coordinate systems; for planning purposes, road centerlines
are usually re-surveyed and stored in geographic information system (GIS)
files, typically tied to regional or global coordinate systems (e.g. latitude-longitude,
state plane or Universal Transverse Mercator, UTM). Paramics treats road sections as straight line segments or
circular arcs — these are amenable to modeling driver response to curvature,
but the geometric representations are so different from those used
in CAD and GIS files that they are incompatible. Consequently road
geometry files for Paramics are re-created by laborious manual effort.
The objective of this project is to facilitate the translation of files from
ESRI's ArcView format to Paramics. The principal deliverable of this project is a software tool, nicknamed S2P
(Shapefile to Paramics), which inputs a GIS shape file, processes it according
to user preferences, and outputs a set of files for Paramics. S2P outputs will have
to be edited in some areas, where there are unusual street configurations,
or where there are data errors or unusual coding practices in the GIS file.
This is partly due to the inevitable disconnect between multipurpose GIS
files, which are available on a continuum of scale and accuracy, and Paramics
needs, which require a specific scale and accuracy level. Many GIS files
contain insufficient detail; some of the high end products may contain too
much detail. Code (for Windows®)
- Executable (Version
3.0d, 2003-06-30), compressed set, includes run time library (DLL), default
initialization file (INI) and user's manual (PDF). Copy this to a directory
such as C:\Program Files\S2P and extract the component files.
- User's Manual
(Version: 3.0d, 2003-06-30)
Sample data
Note that by default, S2P is configured to work with GDT files.
Appropriate field names are set in the initialization file, S2P.INI,
packaged with the code. Some of the following are GDT extracts, some are
not. Non-GDT files require different initialization (INI) files to be loaded
using the File|Load Alternate INI command in S2P. It is
recommended that you download each data set to a separate directory, with
its corresponding INI file. The default S2P.INI in the executable folder
can then be left unmodified.
- Santa Barbara: Fairview overpass and ramps
[map] [data,
INI included]. Modified from GDT with simplified topology most appropriate
for S2P — ideally input files should be at this level of detail: city
streets as single lines, freeways as double lines. The east-bound on-ramp
joins the freeway as an additional lane, therefore Paramics' special ramp
handling does not apply. The westbound on-ramp merges with the #2 freeway
lane, therefore the acceleration lane is seen. Note that the DBF does not
have a feature class code field, so the INI uses the road name to distinguish
the freeway (US-101) from other road classes. Projection: UTM.
- Santa Barbara: freeway extract [map] [data].
Unmodified extract from GDT, use standard INI. Projection: Albers.
- Santa Barbara: urban extract [map] [data].
Unmodified extract from GDT, use standard INI. Projection: Albers.
- Santa Barbara: winding mountain extract [map] [data]. Unmodified
extract from GDT, use standard INI. Projection: Albers.
- Santa Barbara: ramp extract (1 ramp eastbound) [map] [data]. Unmodified
extract from GDT, use standard INI. Projection: Albers.
- Santa Barbara: ramp extract (2 ramps, eastbound and
westbound) [map] [data]. Unmodified extract from GDT, use standard
INI. Projection: Albers.
- Los Angeles major [map]
[data, INI included]. This file
was used for early testing and examples. There are numerous data errors
and the file is NOT of appropriate quality for generating Paramics
files. Projection: unknown.
- Los Angeles: all streets [map] [data, 4 Mb, INI included]. Complete
street coverage, quality better than "Los Angeles major" but also not
appropriate for Paramics. Projection: unknown, same as Los Angeles major.
Final Report
Final Report describes product design issues in detail, and includes a test report by UC Berkeley
