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I'm new to QGIS so I'm not sure if I am missing a plug-in or something.

I have a layer showing demographic data and a layer with series of points.

How do I highlight features to get demographic data from a three mile radius of each point?

There are a total of over 1000 points I want to do this with so I am hoping there is a way to avoid doing this manually (the picture here has 70 of the points on it).

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  • Can we assume the "demographic layer" is a single layer of polygons? Do you need any feature to have all its extent within 3 miles, or just some of its extent, or its centroid? Commented Feb 11, 2023 at 9:22

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I think translated to GIS-speak you want to create a 3 mile buffer around each point, then intersect the buffer layer with the demographic polygon layer. That returns a layer where each new polygonal featyre has an ID for the point layer, and ID for the polygon layer, and the attributes of each.

Then you can do things like add up the population of the polygon layers for polygons within 3 miles of each of the points.

You might want to do some adjustment for area, for example is the buffer just clips a tiny part of a polygon you may have to weight the population total by the fraction of that polygon area under the buffer circle. This can all be done with the QGIS expression engine.

Hard to be more specific without details of your demographic polygon layer (and clarification that my interpretation into GIS-speak is correct!)

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