MICHIGAN STATEWIDE TRANSPORTATION MODELING SYSTEM. VOLUME II-B. TREE PLOTTING WITH INTERACTIVE GRAPHICS. STATEWIDE TRANSPORTATION PLANNING PROCEDURES

A large part of the time involved in model network calibration is usually reserved for verifying that the shortest driving-time paths between zones are correct. This traditionally involves plotting a "tree" (the set of travel paths between one zone and all other zones) for a large number of key zones. Because an agency usually has only one or two flat-bed or drum plotters to serve everybody, there is at least a day's delay between submission of the batch plot run and delivery of the finished plot. This contributes to one of the big arguments against model development, "We can't do it because it takes too long." This report shows how a Tektronix full-graphic, cathode-ray-tube computer terminal can be used for tree plotting, cutting turnaround time from a day to a few minutes. Statewide's interactive tree plotter also gives the analyst the capability of quickly windowing in on parts of the tree he wants to explore in more detail. This becomes especially important when one realizes that each blowup necessitates a separate plot run in a batch-oriented system. The ability to view a selected tree quickly is also useful in the day-to-day application of a modeling system. Questions such as, "Why are these links higher (or lower) than expected?" can often be answered with one or two tree plots. However, in this environment, the analyst often needs to plot several trees before the answer is apparent. Often, he does not even know for sure when he starts which trees he should be plotting. Interactive graphics can shave the elapsed time between question and answer by up to 95%. /Author/

  • Corporate Authors:

    Michigan Department of Transportation

    State Transportation Building, 425 West Ottawa Street, P.O. Box 30050
    Lansing, MI  United States  48909
  • Authors:
    • Gotts, T L
  • Publication Date: 1977-1

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00307624
  • Record Type: Publication
  • Report/Paper Numbers: Vol II-B Monog Ser
  • Files: TRIS, STATEDOT
  • Created Date: Jun 9 1980 12:00AM