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I have a large SpatialLinesDataFrame (~23000 features) and a SpatialPolygonsDataFrame (8 features). I want to make 8 new variables, each with the lines that are on the same locations as the polygons. This should be easy, but I can't find the right way.

I tried the sp::over method, but it returns the error: Don't Kont how to get path data from object of class data.frame. I assume that this is because in the help section there is not a method where x = SpatialLinesDataFrame and y = SpatialPolygonsDataFrame.

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In the future, please ask a good question by providing some example data as below:

library(raster)
cds <- rbind(c(-125,0), c(0,60), c(40,5), c(15,-45))
lines <- spLines(cds, cds-20, cds+20, attr=data.frame(Lid=1:3))

p1 <- rbind(c(180,20), c(140,-55), c(10, 0), c(140,60), c(180,20))
p2 <- rbind(c(-10,0), c(-140,-60), c(-160,0), c(-140,55), c(-10,0))
pols <- spPolygons(p1, p2, attr=data.frame(Pid=1:2))

plot(pols)
lines(lines, col='blue')

Now you can do

x <- intersect(lines, pols)

You can use subsetting to get the lines that match a specific polygon

LP1 <- x[x$Pid == 1, ]

Perhaps wrapped in a lapply to get a list

p <- lapply(1:length(pols), function(i) x[x$Pid == i, ])

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