[R] Identify points that lie within polygon

[Ally]

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...
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> rocks...1k
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> Sent from my phone. Please excuse my brevity.
> 
> Ally <a.rushworth at .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
>>
>>
>>
>>
>>--
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>>
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> 
> ______________________________________________
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> and provide commented, minimal, self-contained, reproducible code.
> 




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