[R-sig-Geo] raster CRS changes on tis own

[Roger Bivand]

Please provide a completely reproducible example, otherwise nobody can say 
that this isn't simply a feature of your data. I can't see why helpers 
should be expected to create an example for you, which may not correctly 
represent your problem.

Roger


On Tue, 13 Nov 2012, Agustin Lobo wrote:

> Sorry I forgot my session info:
>> sessionInfo()
> R version 2.15.2 (2012-10-26)
> Platform: x86_64-pc-linux-gnu (64-bit)
>
> locale:
> [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C
> LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8
> LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8
> [7] LC_PAPER=C                 LC_NAME=C
> LC_ADDRESS=C               LC_TELEPHONE=C
> LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C
>
> attached base packages:
> [1] stats     graphics  grDevices utils     datasets  methods   base
>
> other attached packages:
> [1] rgdal_0.7-5   raster_2.0-12 sp_0.9-99
>
> loaded via a namespace (and not attached):
> [1] grid_2.15.2     lattice_0.19-30 tools_2.15.2
>
> Agus
>
> On Tue, Nov 13, 2012 at 10:41 AM, Agustin Lobo <alobolistas at gmail.com> wrote:
>> Hi!
>> I modify the CRS of a raster object:
>>> vinedomosaicMCA03 <- brick(paste(mosdir,"mosaico_envi.dat",sep="/"))
>>> proj <- CRS("+init=epsg:3042")
>>> proj
>> CRS arguments:
>>  +init=epsg:3042 +proj=utm +zone=30 +ellps=GRS80
>> +towgs84=0,0,0,0,0,0,0 +units=m +no_defs
>>> projection(vinedomosaicMCA03) <- proj
>>> vinedomosaicMCA03
>> class       : RasterBrick
>> dimensions  : 1486, 1162, 1726732, 6  (nrow, ncol, ncell, nlayers)
>> resolution  : 0.170881, 0.170881  (x, y)
>> extent      : 578587.4, 578785.9, 4722025, 4722279  (xmin, xmax, ymin, ymax)
>> coord. ref. : +init=epsg:3042 +proj=utm +zone=30 +ellps=GRS80
>> +towgs84=0,0,0,0,0,0,0 +units=m +no_defs
>> data source : /media/Iomega_HDD/UAVetal/vinedo/Clara_final/mosaico_envi.dat
>> names       : mosaico_envi.1, mosaico_envi.2, mosaico_envi.3,
>> mosaico_envi.4, mosaico_envi.5, mosaico_envi.6
>>
>> But then, after a reordering, the CRS changes again on its own:
>>> vinedomosaicMCA03v2 <- subset(vinedomosaicMCA03,c(3,1,2,4,5,6))
>>> vinedomosaicMCA03v2
>> class       : RasterStack
>> dimensions  : 1486, 1162, 1726732, 6  (nrow, ncol, ncell, nlayers)
>> resolution  : 0.170881, 0.170881  (x, y)
>> extent      : 578587.4, 578785.9, 4722025, 4722279  (xmin, xmax, ymin, ymax)
>> coord. ref. : +proj=utm +zone=30 +ellps=WGS84 +towgs84=0,0,0,0,0,0,0
>> +units=m +no_defs
>> names       : mosaico_envi.3, mosaico_envi.1, mosaico_envi.2,
>> mosaico_envi.4, mosaico_envi.5, mosaico_envi.6
>> min values  : NA, NA, NA, NA, NA, NA
>> max values  : NA, NA, NA, NA, NA, NA
>>
>> The correct CRS is conserved if I write to GTiff:
>>> projection(vinedomosaicMCA03v2) <- proj
>>> vinedomosaicMCA03v2
>> class       : RasterStack
>> dimensions  : 1486, 1162, 1726732, 6  (nrow, ncol, ncell, nlayers)
>> resolution  : 0.170881, 0.170881  (x, y)
>> extent      : 578587.4, 578785.9, 4722025, 4722279  (xmin, xmax, ymin, ymax)
>> coord. ref. : +init=epsg:3042 +proj=utm +zone=30 +ellps=GRS80
>> +towgs84=0,0,0,0,0,0,0 +units=m +no_defs
>> names       : mosaico_envi.3, mosaico_envi.1, mosaico_envi.2,
>> mosaico_envi.4, mosaico_envi.5, mosaico_envi.6
>> min values  : NA, NA, NA, NA, NA, NA
>> max values  : NA, NA, NA, NA, NA, NA
>>
>>> writeRaster(vinedomosaicMCA03v2,file="mosaico_enviv2",overwrite=T,format="GTiff")
>> class       : RasterBrick
>> dimensions  : 1486, 1162, 1726732, 6  (nrow, ncol, ncell, nlayers)
>> resolution  : 0.170881, 0.170881  (x, y)
>> extent      : 578587.4, 578785.9, 4722025, 4722279  (xmin, xmax, ymin, ymax)
>> coord. ref. : +proj=utm +zone=30 +ellps=GRS80 +units=m +no_defs
>> data source : /media/Iomega_HDD/UAVetal/vinedo/RNavarra/mosaico_enviv2.tif
>> names       : mosaico_enviv2.1, mosaico_enviv2.2, mosaico_enviv2.3,
>> mosaico_enviv2.4, mosaico_enviv2.5, mosaico_enviv2.6
>> min values  : 0, 0, 0, 0, 0, 0
>> max values  : 175, 224, 179, 199, 196, 204
>>
>> But it is modified if I write to ENVI format:
>>
>>> writeRaster(vinedomosaicMCA03v2,file="mosaico_enviv2",overwrite=T,format="ENVI")
>> class       : RasterBrick
>> dimensions  : 1486, 1162, 1726732, 6  (nrow, ncol, ncell, nlayers)
>> resolution  : 0.170881, 0.170881  (x, y)
>> extent      : 578587.4, 578785.9, 4722025, 4722279  (xmin, xmax, ymin, ymax)
>> coord. ref. : +proj=utm +zone=30 +datum=NAD27 +units=m +no_defs
>> +ellps=clrk66 +nadgrids=@conus, at alaska, at ntv2_0.gsb, at ntv1_can.dat
>> data source : /media/Iomega_HDD/UAVetal/vinedo/RNavarra/mosaico_enviv2.envi
>> names       : mosaico_enviv2.1, mosaico_enviv2.2, mosaico_enviv2.3,
>> mosaico_enviv2.4, mosaico_enviv2.5, mosaico_enviv2.6
>> min values  : 0, 0, 0, 0, 0, 0
>> max values  : 175, 224, 179, 199, 196, 204
>>
>>
>> Is this a bug in raster or rgdal, or am I doing something wrong?
>>
>> Agus
>
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-- 
Roger Bivand
Department of Economics, NHH Norwegian School of Economics,
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