3 messages · Marcio Pupin Mello, Roman Luštrik
Dear list, I have a RasterLayer (raster package) and want to select "n" smallest values from it (values and coordinates). I figured out that the which.min function in the raster package give me the coordinate of the smallest value. But how could I get the 10 smallest values? I'm using last version of R for Windows and all the packages. Thanks in advance,
Marcio www.dsr.inpe.br/~mello
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Great! I was trying "order(my.r)" instead of "order(my.r[])". Thank you Roman! Cheers, Marcio www.dsr.inpe.br/~mello
Something like this?
library(raster)
my.r <- raster(nrow = 10, ncol = 10)
my.r[] <- runif(ncell(my.r))
plot(my.r)
cell.numbers <- order(my.r[])
cell.numbers[1:10]
[1] 32 33 81 12 28 98 100 34 69 2
xyFromCell(my.r, cell.numbers[1:10])
x y
[1,] -126 27
[2,] -90 27
[3,] -162 -63
[4,] -126 63
[5,] 90 45
[6,] 90 -81
[7,] 162 -81
[8,] -54 27
[9,] 126 -27
[10,] -126 81
points(xyFromCell(my.r, cell.numbers[1:10]))
Cheers,
Roman
On Mon, Nov 11, 2013 at 2:05 PM, Marcio Pupin Mello <mello at ieee.org> wrote:
Dear list,
I have a RasterLayer (raster package) and want to select "n"
smallest values from it (values and coordinates). I figured out that the
which.min function in the raster package give me the coordinate of the
smallest value. But how could I get the 10 smallest values?
I'm using last version of R for Windows and all the packages.
Thanks in advance,
--
Marcio
www.dsr.inpe.br/~mello
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Marcio www.dsr.inpe.br/~mello