[GRASS-dev] [bug #4438] (grass) export of AAIGrid and arc incorrect

[Request Tracker]

this bug's URL: http://intevation.de/rt/webrt?serial_num=4438
-------------------------------------------------------------------------

Subject: export of AAIGrid and arc incorrect

Platform: GNU/Linux/x86
grass binary for platform: Compiled from Sources
GRASS Version: cvs 08.05.2006

Hello, 

concerning the export of AAIGrid (r.out.gdal) and ArcInfo Ascii Grid 
(r.out.arc) an incorrect output occurs if the nsres/ewres in GRASS is not 
equal - AAIGrid/arc stores only one value for res. 

The difference between the resolutions is (in my case) small (3-> decimal 
place) hence the incorrect export is only visible if high numbers of row/col 
exist (high resolution imagery/covering continental scales). 

The remedy is to resample the image to an equal nsres ewres. The problem is 
located in the data format and not GRASS so I would suggest to either

1. prompt a warning if nsres != ewres

or

2. do an automatic resampling with equal nsres/ewres with an info prompt

otherwise the exported files have a wrong geolocation.

regards, Martin





-------------------------------------------- Managed by Request Tracker