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I'm creating a map with two shapefiles:

  1. A polygon of counties
  2. Points of cities

I used the function Intersect to group the cities in each county.

I'm trying to get the number of cities in each county to show up in the legend.

For example, in county A there are 16 cities, in county B there are 7 cities and so on.

I'm trying to create a choropleth map that shows the number of cities in each county.

12

You can get a count of cities in each county by doing a spatial join. This will create a new shapefile with a new column in the attribute table called "Count."

You can set your map symbology based on that column to create a choropleth map.

7

You don't mention what version of ArcGIS you are using,but if it is 10.1 you can add the feature count in the legend

You can also add feature counts to your legend by checking the Show feature count check box.

http://resources.arcgis.com/en/help/main/10.1/index.html#//00s900000023000000

Its half way down the page.

0

Here is a long process but it worked for me many times: first with Spatial Join target points and join the attribute of the countries to your city points. Remember to change Joint operation to one-to-many.

then your points have the values of your countries, then you will have a join_FID field added along with other attributes of the countries. right click on the header and click summarize, choose join_FID and find a field which you can check the count calculation. hit ok and you will have a table with join_FID and count of the points

the last step is just joining the data from the Join_FID field of summarize table with your Polygon SHP object ID.

now you have the count of the points for each polygon.

the second method uses QGIS with is way easier. you just have to use join by location tool.

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