[GRASS-user] exporting raster asc to qgis, axis flipped E to W?

[Nikos Alexandris]

* Tyler Smith <tyler at plantarum.ca> [2015-05-08 14:34:41 -0400]:

> On Fri, May 8, 2015, at 02:23 PM, Nikos Alexandris wrote:
> > 
> > What does `g.region -p` say about?
> 
> g.region -p rast=tri_median at PERMANENT
> projection: 3 (Latitude-Longitude)
> zone:       0
> datum:      wgs84
> ellipsoid:  wgs84
> north:      46:53:04.633938N
> south:      34:44:13.536462N
> west:       94:51:40.938811W
> east:       68:50:28.1616W
> nsres:      0:00:29.993894
> ewres:      0:00:30.004093
> rows:       1458
> cols:       3122
> cells:      4551876
> 
> > 
> > Shouldn't it be:
> > 
> > east: 94:51:40.938811W
> > west: 68:50:28.1616W
> > 
> > ( east > west )
> > 
> 
> Not in this case - note that the east boundary is 68 degrees WEST, which
> is further east than the west boundary at 94 degrees WEST.

I see. Then it is correct :-). I am trying to do some test with your
region settings (with res=30). The exported file (just some random cells set to 100)
begins with:

north: 46:53:30N
south: 34:44N
east: 68:50W
west: 94:52W
rows: 1459
cols: 3124

which is correct and gdalinfo reports:

Driver: GRASSASCIIGrid/GRASS ASCII Grid
Files: test_random_points
Size is 3124, 1459
Coordinate System is `'
Origin = (94.000000000000000,46.000000000000000)
Pixel Size = (-0.008322663252241,-0.008224811514736)
Corner Coordinates:
Upper Left  (  94.0000000,  46.0000000)
Lower Left  (  94.0000000,  34.0000000)
Upper Right (  68.0000000,  46.0000000)
Lower Right (  68.0000000,  34.0000000)
Center      (  81.0000000,  40.0000000)
Band 1 Block=3124x1 Type=Int32, ColorInterp=Undefined

So the same.  Maybe ask in gdal-dev?

Nikos


> Also, my crude fix of replacing 94:51:40.93W with -94:51:40.93 in the
> asc header didn't really fix the problem - the projection still doesn't
> quite match up with the destination in QGis.
> 
> Thanks,
> 
> Tyler