Dear all,

I have a SpatialGridDataFrame which I read from grass
   myrast<-readRAST6("DRENVAL")

Now I attrib a sequential number for each pixel with:
    myrast @ data[[1]]<-1:dim(myrast @ data)[1]

Now I need to select record by record, from 1 to N, get the bbox()
from each record, set the g.region and compute somethings
for the region of each pixel.

But my problem relies on subset each of object. I tryed something like:

for (i in 1:dim(myrast @ data)[1]) {
 myrast.pixel<-subset(myrast, myrast @ data$DRENVAL==i)
 OR
 myrast.pixel<-myrast[myrast @ data$DRENVAL==i,]
 ...my processing
 }
But I don't know how subset the SGDF. Sorry for not provide a reproducible
example.

Bests,

milton
> sessionInfo()
R version 2.9.0 alpha (2009-03-26 r48224)
i386-pc-mingw32
locale:
LC_COLLATE=English_Canada.1252;LC_CTYPE=English_Canada.1252;LC_MONETARY=English_Canada.1252;LC_NUMERIC=C;LC_TIME=English_Canada.1252
attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base
other attached packages:
[1] spgrass6_0.6-5   XML_2.3-0        rgdal_0.6-7      maptools_0.7-20
sp_0.9-32
[6] foreign_0.8-34   gpclib_1.4-3     adehabitat_1.8.2 ade4_1.4-10
loaded via a namespace (and not attached):
[1] grid_2.9.0      lattice_0.17-20

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