readRAST6: too many open files

On Tue, 5 May 2009, Roger Bivand wrote:

On Tue, 5 May 2009, Agustin Lobo wrote:

Roger,

After upgrading, the test works with plugin=F,
while plugin=T produces the same result.

I find this too on Fedora 10, plugin=TRUE fails after a hundred or so 
calls, and then crashes R on a further command. With plugin=FALSE, 
there is no problem at all. The problem then lies in the plugin 
driver, which isn't anything that spgrass6 can do anything about. It 
looks as though the plugin is opening file handles to GRASS files but 
not closing them. I'll try to ask on the GDAL and grass-dev lists. 
For the time being, it seems best to use plugin=FALSE in readRAST6().

A follow-up. The previous results were using a GDAL 1.5.3 RPM, linking 
against GRASS 6.3 libraries. Having built a fresh GDAL 1.6.0 from 
source, linked against a fresh GRASS 6.4.0 RC4, the plugin now works 
and does not crash R. Browsing the GDAL GRASS raster plugin, there 
seem to have been important commits between GDAL 1.5.3 and 1.6.0 
(possibly also 1.5.4, untested). GRASS has also changed between 6.3 
and 6.4.0 release candidates. So a possible solution is to upgrade 
both GDAL and GRASS, or at least GDAL.

Roger

Also, ignore.stderr=T yields:

ERROR 6: SetColorTable() only supported for Byte or UInt16 bands in 
TIFF format.

This is a GRASS version issue, more recent GRASS support a flag to 
avoid r.out.gdal trying to write non-existent colour tables. Could 
you repeat your GRASS version:

execGRASS("g.version")

should do it.

WARNING: Input raster map constains cells with NULL-value (no-data). 
The
value 999 was used to represent no-data values in the input
map.You can specify nodata value by nodata parameter.

Maybe set a NODATA= value in the readRAST6() call to avoid heuristics 
trying to find a possible value?

Roger

/media/Transcend/Montseny/GrassData//carlos/A_TOTAL/.tmp/caminoccg/nomdum 
has GDAL driver GTiff
and has 94 rows and 116 columns

which is not including any more the first lines that we had with the 
previous version:

raster map/current region mismatch detected in components:
cols rows origin.northing origin.easting
TRUE TRUE FALSE TRUE
set plugin=TRUE to override; continuing with plugin=FALSE

Now we have:

sessionInfo()

R version 2.9.0 (2009-04-17)
i486-pc-linux-gnu

locale:
LC_CTYPE=es_ES.UTF-8;LC_NUMERIC=C;LC_TIME=es_ES.UTF-8;LC_COLLATE=es_ES.UTF-8;LC_MONETARY=C;LC_MESSAGES=es_ES.UTF-8;LC_PAPER=es_ES.UTF-8;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=es_ES.UTF-8;LC_IDENTIFICATION=C 


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

other attached packages:
[1] spgrass6_0.6-4 XML_1.95-3 rgdal_0.6-7 sp_0.9-36

loaded via a namespace (and not attached):
[1] grid_2.9.0 lattice_0.17-22

We are trying now with our process, that takes much longer than the 
test, we'll let you know.

Thanks!

Agus