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unique values symbology for current extent

December 17 2008 | 0 comments
Categories: Cartographic Design, Cartographic Effects, Symbology

Is there a way to apply a Unique Values renderer just to layer features in the current map extent? Layers like ZIP codes and census tracts have tens of thousands of features. When I'm panning the map, I want the features in the current extent to have different colors, but I don't care about the features offscreen. The "Add Values" button isn't efficient, because the values change as I pan (and I don't know what they are in advance anyway). Symbolizing the entire layer takes a while and also seems to slow down access to the layer properties. Thanks.

Mapping Center Answer:

In that case, unique values on the field with way too many values to matter in terms of what a specific color means should be solved a different way.  The most important quality the map should exhibit for this layer is that one feature is different from its neighbors.  The "Four Color Map" tool is the solution.  It will add a field to your data and assign one of four values to the field--making the Unique values problem much easier to handle.

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