r.in.ascii

[Stephan Haverkamp]

On Fri, 16 Jan 1998, Houxiang Wang GEO Grad 96 wrote:

> Hi dear GRASS users:
> 
> I am having troubles importing files from idrisi, and hereby securing helps from 
> you.
> 
> I have exported idrisi files using ascii raster format. And then I edited the 
> file (deleting the first two lines of projection and zone, so there are six 
> lines as the header). After ftp them to GRASS, I ran r.in.ascii. Everything 
> looked okay. However, when I tried to display it, it was blank--three or four 
> non-sense colorful lines at the top, and elsewhere was just white. I checked the 
> file under cellhd directory. It reads:
> 	 proj:       1
> 	 zone:       16
> 	 north:      4386270
> 	 south:      4351770
> 	 east:       730110
> 	 west:       686490
> 	 cols:       1454
> 	 rows:       1150
> 	 e-w resol:  30
> 	 n-s resol:  30
> 	 format:     0
> 	 compressed: 1
> 	 
> Actually it is in UTM 16, and it is within the current region. I am not sure of 
> the last sentence. Does it mean that the file is compressed so that GRASS could 
> not process it correctly?
> 
> I also tried to export from idrisi using binary format, which produces two 
> directories--cell and cellhd, each containing one file of the same name. In 
> grass I then ran r.support to get a color table for it. However, this time it 
> was even worse--I couldn't get the file done.
> 
> I am stuck. Could someone give me some hints? Thanks a lot in advance.
> 
> Houxiang
> 

Dear Houxiang,
I had also some problems when exchanging maps from Idrisi to Grass but now
it works. I used Idrisi for Windows 1.0 and Grass 4.1. 
It is correct to delete the first two line of the Idrisi output-data-file 
and to use ASCII-data-format.
I did not use UTM but Transverse Mercator and Geographic projection (proj 
3 and 99). I solved my problem by changing the format of east/west and
north/south data. (Idrisi format does not fit Grass format, so errors
occured). So I would suggest check the digits of your input by g.region.

Good luck,
Stephan 
---------------------------------------------------------------
Stephan Haverkamp
Institut für Landeskultur          
Senckenbergstr. 3                    priv.: Grabenstr. 14
D-35390 Giessen                             35396 Giessen
Tel.: 0641/99 37384                         Tel.: 0641/54470
Fax.: 0641/99 37389
e-mail: Stephan.Haverkamp at agrar.uni-giessen.de
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