[STATSGRASS] import DTM with readRAST6()

Markus Neteler neteler at itc.it
Thu Jul 12 08:18:11 EDT 2007


On Thu, Jul 12, 2007 at 12:50:57PM +0200, Matteo Dall'Amico wrote:
> Hi Markus,
> I own a MacBookPro with Intel processor and I am running Mac OSX version 
> 10.4.10.
> I have installed GRASS 6.2.1 and R 2.5.1.
> I have tried all yesterday to read the raster DTM without success.
> This is what I get:
>
> >trent.int<-readRAST6("DTM_integer")
> Creating BIL support files ...
> Header File = 
> /Users/Matteo/Documents/DataGrass/GBovest/Permafrost/.tmp/nilo.ing.unitn.it/DTM_integer.hdr
> World File = 
> /Users/Matteo/Documents/DataGrass/GBovest/Permafrost/.tmp/nilo.ing.unitn.it/DTM_integer.wld
> Exporting Raster as integer values (bytes=2)
> Using the Current Region settings ...
> north=5158000.000000
> south=5058500.000000
> east=1729700.000000
> west=1611600.000000
> r=995
> c=1181
>
> Percent complete:  100%
> r.out.bin complete.
>
> > summary(trent.int)
> Object of class SpatialGridDataFrame
> Coordinates:
>               min     max
> coords.x1 1611600 1729700
> coords.x2 5058500 5158000
> Is projected: TRUE
> proj4string :
> [+proj=tmerc +lat_0=0.0000000000 +lon_0=9.0000000000 +k_0=0.9996000000
> +x_0=1500000.0000000000 +y_0=0.0000000000 +a=6378388 +rf=297 +no_defs
> +towgs84=-225.000,-65.000,9.000]
> Number of points: 2
> Grid attributes:
>   cellcentre.offset cellsize cells.dim
> 1           1611650      100      1181
> 2           5058550      100       995
> Data attributes:
>   DTM_integer
> Min.   :-32768
> 1st Qu.: -3624
> Median : -3624
> Mean   : -1991
> 3rd Qu.:  1028
> Max.   : 32525
>
> > print(trent.int at data[100000:100150,])
>   [1]  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624
> [11]  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624
> [21]  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624
> [31]  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624
> [41]  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624
> [51]  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624
> [61]  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624
> [71]  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624
> [81]  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624
> [91]  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624  -3624
> [101]  -3624  -3624  -3624  -3624 -19703  12298  22794   2058  -8951 -17911
> [111] -27895  29961  27401 -32759 -25079 -13815  15370  25354  30986 -30710
> [121] -15094   6923   -758  -7670 -17654 -22518 -20214 -30710  21258  10506
> [131]  17930 -28150 -26102  28938  23818   -247  26889 -31991 -15607  10761
> [141]  -4856 -18936  28936  14088  -4857 -21241   9223 -11002 -17658  -9722
> [151]   5639
>
> As you can see, it doesn't distinguish the NODATA: instead of -9999 it uses 
> -3624.
> Also in summary there is no notice of the NODATA.
>
> I downloaded all the packages and then, from the terminal, I installed them 
> using:
>
> R CMD INSTALL name_of_package

I would update like this:

http://grass.itc.it/statsgrass/grass6_r_install.html

# you need to be connected to the Internet to use these commands:
install.packages(c("sp","spgrass6","rgdal","maptools"), dependencies=TRUE)

> I really think there are problems with my spgrass6 package and MacOS 
> system.
> Any idea?

Could you try a more recent GRASS?
http://www.kyngchaos.com/software/unixport/grass/

Markus

> Thanks,
> Matteo
>
> On 12 Jul 2007, at 11:08, Markus Neteler wrote:
>
>>
>> hi Matteo,
>>
>> I have just made a test on a fresh installed machine with latest R
>> and sp* packages using a synthetic DEM (still don't have a real
>> DEM on this computer):
>>
>> GRASS 6.3.cvs (bellunoOvest):~ > r.surf.fractal dem
>> Steps=1
>> Preliminary surface calculations.
>> Calculating surface 1 (of 1)
>> GRASS 6.3.cvs (bellunoOvest):~ > R
>>
>> R version 2.5.1 (2007-06-27)
>> ...
>>> trentino.grid<-readRAST6("dem")
>> Error: could not find function "readRAST6"
>>> library(spgrass6)
>> Loading required package: sp
>> Loading required package: maptools
>> Loading required package: foreign
>> Loading required package: rgdal
>> Geospatial Data Abstraction Library extensions to R successfully loaded
>>
>>> trentino.grid<-readRAST6("dem")
>> Creating BIL support files ...
>> Header File =
>> /home/neteler/grassdata/bellunoOvest/PERMANENT/.tmp/localhost/dem.hdr
>> World File =
>> /home/neteler/grassdata/bellunoOvest/PERMANENT/.tmp/localhost/dem.wld
>> Exporting Raster as double values(bytes=8)
>> Using the Current Region settings ...
>> north=5175700.000000
>> south=5084600.000000
>> east=1787600.000000
>> west=1706300.000000
>> r=911
>> c=813
>>  100%
>>
>>> summary(trentino.grid)
>> Object of class SpatialGridDataFrame
>> Coordinates:
>>               min     max
>> coords.x1 1706300 1787600
>> coords.x2 5084600 5175700
>> Is projected: TRUE
>> proj4string :
>> [+proj=tmerc +lat_0=0 +lon_0=9 +k=0.999600 +x_0=1500000 +y_0=0 +no_defs
>> +a=6378388 +rf=297 +towgs84=-225.000,-65.000,9.000 +to_meter=1]
>> Number of points: 2
>> Grid attributes:
>>   cellcentre.offset cellsize cells.dim
>> 1           1706350      100       813
>> 2           5084650      100       911
>> Data attributes:
>>       dem
>>  Min.   :-604.82
>>  1st Qu.:-289.55
>>  Median :  49.31
>>  Mean   :  23.07
>>  3rd Qu.: 334.70
>>  Max.   : 669.46
>>
>>> system("r.info -r dem")
>> min=-604.821087
>> max=669.457656
>>
>>> system("r.info -t dem")
>> datatype=DCELL
>>
>> Looks all functional. I am using 6.3, though. Do you use a 64bit machine
>> (like me)? Probably there were 64bit fixes after GRASS 6.2.1, I don't
>> remember in this moment.
>>
>> Did you run
>> update.packages()
>> for your R installation?
>>
>> ciao
>> Markus
>>
>> -- 
>> View this message in context: 
>> http://www.nabble.com/import-DTM-with-readRAST6%28%29-tf4049321.html#a11556201
>> Sent from the Grass - Stats mailing list archive at Nabble.com.
>>
>> _______________________________________________
>> statsgrass mailing list
>> statsgrass at grass.itc.it
>> http://grass.itc.it/mailman/listinfo/statsgrass
>>
>

-- 
Markus Neteler  <neteler itc it>  http://mpa.itc.it/markus/
FBK-irst -  Centro per la Ricerca Scientifica e Tecnologica
MPBA - Predictive Models for Biol. & Environ. Data Analysis
Via Sommarive, 18        -       38050 Povo (Trento), Italy




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