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I'm working on a basic choropleth map that visualizes one variable for all the counties in a single state. I want to create a map for each county that highlights (or adjusts the border style for) the relevant county boundary. The map will otherwise be identical, showing the whole state, the same variable classes, and so forth. If easier, other style tweaks that draw attention to a specific county would also be suitable. Maps will be used in printed documents.

I'm primarily using QGIS 2.1, but solutions that involve ArcGIS would be fine. Python or other frameworks are acceptable as well, but please reference some documentation if you can so that I'm able to brush up on relevant details.

I've looked into trying to use the QGIS Print Composer Atlas, but it doesn't seem that Atlas alone will yield a solution.

In other words, what's the best way to batch produce maps (to be exported as images) that stylize each individual polygon feature while maintaining the full map extent and other details?

  • You want to show the highlighted county at state not county scale? – artwork21 Dec 10 '15 at 15:13
  • That's right. I want to draw attention to a specific county while keeping the statewide perspective. I'm also considering using an inset, but being able to stylize the county border would be the best solution. – ZeroFlux Dec 10 '15 at 18:16
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The ArcGIS/ArcMap solution for this is:

  1. Create a scale field (long integer) in county layer.
  2. Populate each county value with max state scale in the scale field created in step one (batch calculate these using Field Calculator). This value will differ for each state based on the area and extent of each state broader.
  3. Enable Data Driven Pages (DDP) (using DDP toolbar) on the county layer on the county name field.
  4. On the DDP setup dialog>Extent tab, enable the data driven scale radio option and select the scale field you added and populated.
  5. Make a copy of the county layer in the map TOC (move this on top of other county layer), select Properties>Definition Query and click the Page Definition button, enable the county name field, and select Match option. Finally, in the Properties>Symbology tab make the outline line of this layer stand out (for example a thick red outline with empty fill).

These options will allow the county features to be toggled through using the DDP at the variable state scale and highlight each county feature.

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