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two way display with single line

October 22 2009 | 1 comment
Categories: Map Data, Symbology


I have a street layer center line shapefile. I have values in two fields in each representing either direction. I want to plot and symbolize these values on the street layer. That is with a single line layer I want two symbologies, one for each direction.


Mapping Center Answer:

First, draw you roads with using whatever line symbology you want, then copy and paste the roads layer twice in your Table of Contents.  For the attribute that shows one direction, use a marker line symbol, with arrows to indicate the direction -- but NO line for the roads.  Then for the other direction, use the other attribute with another marker line symbol -- with NO line -- and the arrows going the other direction.  You will likely need to offset the marker symbols so that they do not overlap each other, especially if you only have ONE street centerline.  The result may be that you have the one way marker symbols (arrows) offset from your lines completely so that they fall to the sides of the line, but the advantage to this is that you will at least know which side of the street is going which way.  If you happen to have street centerlines that follow the medians of each of the lanes (that is, you )

Note that offset symbology might pose some problems.  The placement can look confusing, especially around curves.  If your data were digitized in such a way that there are many segments or places where the lines do not connect, or other things that make the street centerlines a bit messy, then these problems will be exacerbate problems with the final symbology.

Of course, we do not know if you plan to symbolize your roads with wide lines or narrow ones, cased symbols or not, and more, so we are just to provide some ideas here.  If you can send us a clearer description or a picture of exactly what you want to do, we will take another shot at this if we have to!

two way display with single line posted by dogis aashiq on Oct 23 2009 12:02AM
Hi ,

Thank you for the response. To give you more idea on what I want to do imagine this:

There is a street with traffic moving in both directions. The amount of traffic moving in both directions can be different. I want to plot this.

What I have:
A street layer.
Amount of traffic in both directions.

What I want to do:
1. A scaled symbology of amount (volume) of traffic, that is high volumes are thicker than low volumes.
2. Though I have only one line (street), I want to show traffic in both directions (from attributes) and also scaled to their value.

hope it is more clear than before. is this all possible in arcview 3.x ?


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