[STATSGRASS] speed of GRASS/R interface

[jarekj at amu.edu.pl]

Roger!

I also notice that of Carlos wrote.

That hangs not occured when spgrass6 was based on r.out.ascii instead of
binary input-output and in fact it was realably faster. Maybe back to
previouis solution be good temporal solution. I also exchange data
between grass and R very often so that hang make me sometimes inpatient

greetengs and regards
Jarek


6/10/2007, "Roger Bivand" <Roger.Bivand at nhh.no> napisał/a:

>On Tue, 2 Oct 2007, Carlos "Guâno" Grohmann wrote:
>
>> I've been thinking about the time it takes to import a raster from GRASS to
>> R. I have some rasters with about 2000 rows and 2500 columns. importing
>> starts fine, creates the header, then goes to 100%, and it hangs there for
>> about 10 minutes, before get ready for the next command.
>> Any way of decrease this waiting time?
>
>I'm looking into this, as far as I can see as of now it is somewhere in 
>the new("SpatialGridDataFrame", ...) call in
>res <- SpatialGridDataFrame(...) in readBinGrid(). Confusingly, the 
>Rprof() output points at unlist() taking 90% of the total run time. I'll 
>let you know where I get.
>
>Roger
>
>>
>> cheers
>>
>> Carlos
>>
>>
>
>-- 
>Roger Bivand
>Economic Geography Section, Department of Economics, Norwegian School of
>Economics and Business Administration, Helleveien 30, N-5045 Bergen,
>Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
>e-mail: Roger.Bivand at nhh.no