How to symbolize topo lines

Question: I’m trying to come up with a straightforward way to symbolize topographic contours from a polyline featureclass. For example, I would like to be able to make multiples of 250 darker lines than the others. Ideally I would like to do this without having to add columns to the featureclasses, and without having to manually specify each contour interval that I want to be dark.

I thought perhaps I could write a definition query that would select multiples of 250, but I have had no luck finding a function that returns a remainder or something along those lines.

Thanks,
Ryan

Answer: Add a short integer field to the contours data.  Calculate that field using an Advanced field calculator statement, like:

k = 0
if [Contour] MOD 250 = 0 then
k = 1
endif

Set the result to = k.

Using a definition query will slow drawing performance to an unacceptable level.

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