Q: My boss would like me to do a composite of coverage studies from five sites in our county. Every time I try it gets about half way through and then tells me there is not enough memory. How can I fix this?
A: When TAP creates a map, it builds a database (default name is SWMAP000.DBF) that contains the drawing elements. I've seen a problem if that file gets to be around 100Mb or larger. If you find that file is a lot smaller than that, then there may be something else going on.
I'm assuming you are able to plot each of the five studies individually, and it's not a problem of a corrupted file in a particular study.
Be sure you have checked the "Points Only" option on the levels form, since drawing a point takes a lot less space in the database than drawing a filled box.
Another factor that can be controlled is the number of points to be plotted from the coverage studies. Usually, if you are plotting five studies the goal is to see the overall coverage. If you ran the original studies, for example, with the step between field strength calculation points at 0.1 mile increment, when you plot all five studies, the density of the points could be reduced and still show essentially the same information. There is a way to force TAP to plot only every second point, or every third point, etc., to reduce the size of the graphic database (as well as reducing the time for the plot).
In the folder where you have TAP installed (such as C:\SWTAP), find the file SWDEFAULTS.INI and open the file with Notepad.
Find a section that starts with the line:
[Map Window]
Right after this line, add the line shown below:
RDBJump = 2
This will plot every second point (setting the value to 3 plots every third point, etc.). Naturally this will reduce the size of the graphic database considerably.
For additional suggestions, see the Plotting Large Coverage Studies FAQ.
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