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You can select by location the features in the blue circle, e.g. using the rules "touch the boundary of" your buffer, then select from the selected feature using "within" your buffer. In your case, you could also select based on the length (they are very small compared with other lines), but the first method is safer. Once this is done, you can either ...


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The gIntersection function from the rgeos library might help you. See the commented code below. library(sp) library(rgeos) pointB <- SpatialPoints(cbind(1,1)) pointC <- SpatialPoints(cbind(4,2)) distanceA2B <- 2 distanceA2C <- 3 # create the circle polygons around the points with the distances polyB <- gBuffer(pointB, width = distanceA2B) ...


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KevinMayall's suggestion of intersecting circles is the easiest. A good theoretical treatment can be found at Wolfram Mathworld, which may get into more detail than you want to get this working (but is nice background for writing a paper about your methodology). This StackOverflow answer has a broken link but outlines a basic approach. First ...


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There are detailed instructions with dialog illustrations for this in the help files. In the layer properties on the symbology tab, choose pie under Charts. Add your fields to be depicted in the chart, then click the Size button at the lower right. That will bring up a dialog that has an option to vary the chart size based on a specific field, such as your ...



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