On Thu, 15 Nov 2012, peleve wrote:
Thanks Robert,
I was able to do it with the following using the 'gpclib" package:
For completeness, please use rgeos rather than gpclib, which we are
advising against strongly, because of the unclear and very restrictive
licence of its included C code. rgeo
Thanks Robert,
I was able to do it with the following using the 'gpclib" package:
p2 <- as(xy, "gpc.poly")
p1 <- as(maparea, "gpc.poly")
plot(setdiff(p1, p2), poly.args = list(col = 3), add = TRUE)
Did exactly what I was looking for. Pretty simple, actually.
Thanks for inspiring me.
Pete
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If you have a polygon for the entire area and one for the area of interest
within it; then I think you could use rgeos::gDifference to create the
polygon you need.
Robert
On Thu, Nov 15, 2012 at 6:19 AM, peleve wrote:
> Thank you very much. That worked, mostly!?! But I see the methodology
> n
Thank you very much. That worked, mostly!?! But I see the methodology now.
I had been thinking about masks, but I was asking the wrong question I now
realize.
In my real application, using your approach, I still have some unwanted bits
left outside of the polygon. I traced it as a left over piec
I think you can do:
x <- raster(akima)
y <- mask( x, SpP[2] )
plot(y)
On Wed, Nov 14, 2012 at 10:45 AM, peleve wrote:
> I have a result from Akima or Loesss interpolation using irregular data
> defined inside a polygon. I only want the results inside the polygon.
> Akima interpolates correc
I have a result from Akima or Loesss interpolation using irregular data
defined inside a polygon. I only want the results inside the polygon.
Akima interpolates correctly inside the polygon but leaves a blue residue
outside the polygon (a result of Akima using a convex hull) that I want to
get rid
