[R-sig-Geo] raster: extract is empty with polygon

[Agustin Lobo]

Hi!
I'm trying to calculate the mean values for a set of polygons.
This is what I do:

require(raster)
require(rgdal)
#SGRGBWBPS125F40
#"read" tif file
SGRGBF40 = brick("/media/TRANSCEND/MONTSENY2008/CALIBRACION2010/DigiPreprocess/TESTCASA/CALSEL/SGRGB/SGRGBWBPS125F40.tif")
> SGRGBF40
class       : RasterBrick
filename    : /media/TRANSCEND/MONTSENY2008/CALIBRACION2010/DigiPreprocess/TESTCASA/CALSEL/SGRGB/SGRGBWBPS125F40.tif
nlayers     : 3
nrow        : 1760
ncol        : 2640
ncell       : 4646400
projection  : NA
min value   : 0 0 0
max value   : 65535 65535 65535
extent      : 0, 2640, 0, 1760  (xmin, xmax, ymin, ymax)
resolution  : 1, 1  (x, y)
> projection(SGRGBF40)
[1] "NA"

#read the shape file
calibf2 = readOGR(dsn="/media/TRANSCEND/MONTSENY2008/CALIBRACION2010/DigiPreprocess/TESTCASA/CALSEL",layer="calibf2",stringsAsFactors=F)
> projection(calibf2)
[1] "+proj=utm +zone=31 +ellps=intl +units=m +no_defs"

> projection(SGRGBF40) = projection(calibf2)

But they do not overlap as shown by
> plot(subset(SGRGBF40,1))
> plot(calibf2,add=T)

and the extracted object is empty
#Calculate mean values for each polygon:
> v <- extract(SGRGBF40, calibf2,fun=mean,nl=3)
> summary(v)
      Length Class  Mode
 [1,] 0      -none- NULL
 [2,] 0      -none- NULL
 [3,] 0      -none- NULL
 [4,] 0      -none- NULL
 [5,] 0      -none- NULL
etc

> sessionInfo()
R version 2.12.2 (2011-02-25)
Platform: i486-pc-linux-gnu (32-bit)

locale:
 [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C
 [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8
 [5] LC_MONETARY=C              LC_MESSAGES=en_US.UTF-8
 [7] LC_PAPER=en_US.UTF-8       LC_NAME=C
 [9] LC_ADDRESS=C               LC_TELEPHONE=C
[11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base

other attached packages:
[1] rgdal_0.6-31 raster_1.7-8 sp_0.9-72

loaded via a namespace (and not attached):
[1] grid_2.12.2     lattice_0.19-17 tools_2.12.2