Hi Carsten,
 
may it helps...., projectRaster() is multiCore/cluster enabled. If you
have a multicore machine place this in front of your things:
 
# if you haven't, first install 
# install.packages("snow")
 
beginCluster(type="SOCK") # "type" is not always needed....but you
avoid possible problems  
 
 
r <- raster(grid100) # to convert the SpatialGrid into a raster
test <- raster("glc2000_v1_1") #reads the GLC data
ex <- projectExtent(test, CRS(proj4string(grid100))) # reprojects the
extent
setOptions(chunksize = 1e+04, maxmemory = 1e+06)
# based on comment in: 
https://r-forge.r-project.org/forum/message.php?msg_id=4025&group_id=294
test2 <- projectRaster(test, ex) # to project the actual GLC-data


cheers, Matteo




>>> Carsten Dormann <carsten.dormann@ufz.de> 21.06.2011 10:47 >>>
Dear all,

I want to compute equal-area grid values for global land cover (GLC2000

data). The equal-area grid is in Mollweide projection.

I use raster to read the GLC-data. Now I want to project these 
WGS84-projected GLC-data into Mollweide.

Even after 24 hours of computing, R was still milling away. I regard 
this as a problem, rather than a consequence of the large data set (54

MB). Correctly so?

Any hints on how to do this correctly appreciated!

[Only in case you were wondering WHY I do this: The next steps will be

to simplify down to only one category (using data == "1") and then use

"aggregate" to actually sum the number of positive pixels in each cell.

I did the whole thing with a 1-degree grid without any problems (taking

roughly 30min for each class).]


Cheers,

Carsten


R-code:

r <- raster(grid100) # to convert the SpatialGrid into a raster
test <- raster("glc2000_v1_1") #reads the GLC data
ex <- projectExtent(test, CRS(proj4string(grid100))) # reprojects the
extent
setOptions(chunksize = 1e+04, maxmemory = 1e+06)
# based on comment in: 
https://r-forge.r-project.org/forum/message.php?msg_id=4025&group_id=294
test2 <- projectRaster(test, ex) # to project the actual GLC-data


sessionInfo()

R version 2.13.0 RC (2011-04-05 r55311)
Platform: i386-apple-darwin9.8.0/i386 (32-bit)

locale:
[1] de_DE.UTF-8/de_DE.UTF-8/C/C/de_DE.UTF-8/de_DE.UTF-8

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

other attached packages:
[1] maptools_0.8-6  lattice_0.19-26 foreign_0.8-44  rgdal_0.6-33 
raster_1.8-12   sp_0.9-80

loaded via a namespace (and not attached):
[1] grid_2.13.0  tools_2.13.0





-- 
Dr. Carsten F. Dormann
Department of Computational Landscape Ecology
Helmholtz Centre for Environmental Research-UFZ
(Department Landschaftsökologie)
(Helmholtz Zentrum für Umweltforschung - UFZ)
Permoserstr. 15
04318 Leipzig
Germany

Tel: ++49(0)341 2351946
Fax: ++49(0)341 2351939
Email: carsten.dormann@ufz.de
internet: http://www.ufz.de/index.php?de=4205

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Commercial Register Number/Registergericht: Amtsgericht Leipzig, 
Handelsregister Nr. B 4703
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Wilfried Kraus
Scientific Managing Director/Wissenschaftlicher Geschäftsführer: Prof.

Dr. Georg Teutsch
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Andreas Schmidt

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