[GRASS-user] r.in.gdal global raster incorrect extents

[Nikos Alexandris]

On Mon, 2008-10-13 at 12:41 -0700, Jamie Adams wrote:
> Hello all,
> 
> When I import a global elevation dataset with extents 180w 90n 180e
> 90s using r.in.gdal, the GRASS raster shows up with w-e extents both
> showing 180E.  While this doesn't seem to be affecting raster
> calculations, afaik, it's causing issues with QGIS.  It displays it
> with it's origin at 180E and extends to 540E.  Has anyone run into
> this problem?
> 
> gdalinfo:
> 
> Driver: GTiff/GeoTIFF
> Files: 2_00-res/out-2_00-nozero-res.tif
> Size is 43200, 21600
> Coordinate System is:
> GEOGCS["WGS 84",
>     DATUM["WGS_1984",
>         SPHEROID["WGS 84",6378137,298.2572235630016,
>             AUTHORITY["EPSG","7030"]],
>         AUTHORITY["EPSG","6326"]],
>     PRIMEM["Greenwich",0],
>     UNIT["degree",0.0174532925199433],
>     AUTHORITY["EPSG","4326"]]
> Origin = (-180.000000000124970,90.000000000000000)
> Pixel Size = (0.008333333333333,-0.008333333333333)
> Metadata:
>   AREA_OR_POINT=Area
> Image Structure Metadata:
>   INTERLEAVE=BAND
> Corner Coordinates:
> Upper Left  (-180.0000000,  90.0000000) (180d 0'0.00"W, 90d 0'0.00"N)
> Lower Left  (-180.0000000, -90.0000000) (180d 0'0.00"W, 90d 0'0.00"S)
> Upper Right ( 180.0000000,  90.0000000) (180d 0'0.00"E, 90d 0'0.00"N)
> Lower Right ( 180.0000000, -90.0000000) (180d 0'0.00"E, 90d 0'0.00"S)
> Center      (  -0.0000000,   0.0000000) (  0d 0'0.00"W,  0d 0'0.00"N)
> Band 1 Block=43200x1 Type=Float32, ColorInterp=Gray
>   NoData Value=10
> 
> r.info:
> 
> +----------------------------------------------------------------------------+
> | Layer:    2_00_res                       Date: Fri Oct 10 17:45:37
> 2008    
> | Mapset:   PERMANENT                      Login of Creator: jamie
>         
> | Location: Bathy
>        
> | DataBase: /work/grass
>        
> | Title:     ( 2_00_res )
>        
> | Timestamp: none
>        
> |----------------------------------------------------------------------------
> |
>        
> |   Type of Map:  raster               Number of Categories: 255
>         
> |   Data Type:    FCELL
>        
> |   Rows:         21600
>        
> |   Columns:      43200
>        
> |   Total Cells:  933120000
>        
> |        Projection: Latitude-Longitude
>        
> |            N:        90N    S:        90S   Res: 0:00:30
>         
> |            E:       180E    W:       180E   Res: 0:00:30
>         
> |   Range of data:    min = -10814.000000  max = -0.010000
>         
> |
>        
> |   Data Description:
>        
> |    generated by r.in.gdal
>        
> |
>        
> |   Comments:
>        
> |    r.in.gdal input="out-2_00-nozero-res.tif" output="2_00_res"
>         
> |
>        
> +----------------------------------------------------------------------------+
> 

1. I am not 100% sure but I think the line "Center      (  -0.0000000,
0.0000000) (  0d 0'0.00"W,  0d 0'0.00"N)" in the geo-metadata should
read enter      (  0.0000000,   -0.0000000) (  0d 0'0.00"W,  0d
0'0.00"N)

(Could it be that the file is not ok?)

2. What doeas g.region -p say? If you get the same value for east and
west it's wrong I guess. west should be, well... west: 180W and east:
180E.

3. Try to set "g.region e=180 s=-90 w=-180 n=90 -p". Re-import again and
check for errors.

Regards, Nikos