Hello,
I’m a GIS student and in my project I need to generate vegetation indexes. I’ve generated it succesfully yesterday using both python2.7 and grass gui .I’m using WinGRASS-6.5.svn-r54428-453 on Win7. Today -I don’t know why- grass started to generate 1 pixel NDVI map. The formula is as simple as it could be: float(b4-b3)/(b4+b3) as most of you already know. My data is not corrupted, I’d saved original maps somewhere else and it was my first check that whether there is a corruption. Also using QGis 1.8.1 I can generate correct NDVI map with same data. You can check it here:
r.info map=ndvi4@PERMANENT
±---------------------------------------------------------------------------+
| Layer: ndvi4@PERMANENT Date: Tue Jan 01 04:06:35 2013 |
| Mapset: PERMANENT Login of Creator: murat |
| Location: newLocation |
| DataBase: D:\gis\grassWS |
| Title: ( ndvi4 ) |
| Timestamp: none |
|---|
| Type of Map: raster Number of Categories: 255 |
| Data Type: FCELL |
| Rows: 1 |
| Columns: 1 |
| Total Cells: 1 |
| Projection: UTM (zone 36) |
| N: 1 S: 0 Res: 1 |
| E: 1 W: 0 Res: 1 |
| Range of data: min = nan max = nan |
| Data Description: |
| generated by r.mapcalc |
| Comments: |
| float(L71175034_03420050627_B40@PERMANENT - |
| L71175034_03420050627_B30@PERMANENT) / |
| (L71175034_03420050627_B40@PERMANENT + |
| L71175034_03420050627_B30@PERMANENT) |
| ±---------------------------------------------------------------------------+ |
| (Tue Jan 01 04:06:51 2013) Command finished (0 sec) |
I uninstalled WinGRASS-6.5.svn-r54428-453 and installed WinGRASS-7.0.svn-r54453-453, I’ve deleted mapset and location and the recrated them also. I couldn’t think anything else please give me some information.