Thanks for the suggestion, got exactly what I needed from library(splancs) ?pip
Alastair Jeff Newmiller wrote > > This is off-topic (not about R), and a quick Web search of "test within > polygon" yields many results, and adding "R" to the search when using > Google provides hints about applying the algorithms in R. > --------------------------------------------------------------------------- > Jeff Newmiller The ..... ..... Go > Live... > DCN:<jdnewmil@.ca> Basics: ##.#. ##.#. Live Go... > Live: OO#.. Dead: OO#.. Playing > Research Engineer (Solar/Batteries O.O#. #.O#. with > /Software/Embedded Controllers) .OO#. .OO#. > rocks...1k > --------------------------------------------------------------------------- > Sent from my phone. Please excuse my brevity. > > Ally <a.rushworth@.ac> wrote: > >>I have a complex 2D polygon with thousands of vertices, and I'd like to >>be >>able to identify points from a large set contained within the polygon, >>and >>was wondering if there might be an efficient way of doing this? Any >>advice >>would be useful! Here is a small example of what I mean: >> >># make polygon >>v1<-c(0,1,1,2,1,3,6,7) >>v2<-c(1,3,3,5,6,7,8,9) >>plot(v1, v2, type = "n" ) >>polygon(v1, v2, lwd = 2, col = "red") >> >># plot a set of candidate grid points >>grid<-seq(0, 10, length.out = 30) >>pts<-expand.grid(grid, grid) >>points(pts, pch = 19, col = 1, cex = 1) >> >>Many thanks! >> >>Alastair >> >> >> >> >>-- >>View this message in context: >>http://r.789695.n4.nabble.com/Identify-points-that-lie-within-polygon-tp4639289.html >>Sent from the R help mailing list archive at Nabble.com. >> >>______________________________________________ >>R-help@ mailing list >>https://stat.ethz.ch/mailman/listinfo/r-help >>PLEASE do read the posting guide >>http://www.R-project.org/posting-guide.html >>and provide commented, minimal, self-contained, reproducible code. > > ______________________________________________ > R-help@ mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > -- View this message in context: http://r.789695.n4.nabble.com/Identify-points-that-lie-within-polygon-tp4639289p4639296.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
