I am observing some behaviors and I'd like to know if this is what one should
expect, if I am doing anything wrong, or if things need some fixing:
1- I am using QGIS 0.8 (preview 1) (because with preview 2, I am not able to
use the GRASS shell under the GRASS tools menu). My platform is Windows 2000.
2- I have a DEM in binary grid format in the QGIS project. The grid is in State
Plane Coord system (Lambert comformal conic), MAssachusetts Mainland NAD 83 in
meters, but when I bring it into QGIS, I need to redefine its projection,
because aparently QGIS doesn't read it and assign it automatically. Is this
always going to be the case?
3-I define the projection of the grid, and I define the projection of the QGIS
project. I create a new GRASS mapset with the same coordinate information.
Then, I proceed to "IMPORT" the grid into a GRASS raster, using the "IMPORT
GDAL RASTER LAYER" in the GRASS tools. While it is importing, I get this
"Warning 4: Unable to find state plane zone in stateplane.csv,
likely because the GDAL data files cannot be found. Using
incomplete definition of state plane zone.
Over-riding projection check.
Proceeding with import... "
But when I look into the stateplane.csv file,
line 44 has that info: 2001, MASSACHUSETTS, MAINLAND, 2, NAD83, 2001, 26986
4- Because the projection of the grid and the mapset are the same, in this case
this is not a big problem, but if they were different, the GDAL import feature
by default OVER-RIDES the projection to match it to the map set, so then, we
would get a GRASS raster with wrongly defined projection, right?
5-After the import, I hit "view output". A raster gets added to the view, but
it is all black. If I right click in properties, I don't see max/min value, but
if I look at the raster properties in the "GRASS tools browser", I see that all
the parameters of the raster seem to be correct, so I recover hopes and I go to
GRASS tools and set a "raster color map". Then, it does not change
automatically, and I have to fo to view> refresh. May be I am expecting too
much, but what would be nice is that when I try to "view the output" in the
first place, a random color map gets assigned to the newly imported raster, so
the user doesn't panic seeing it all black. But if a raster map needs to be
created, could it be automatically refreshed? That by itself would be a nice
Sorry for this long message, I dont want to be a pain. These may be details but
make the experience of beginners and students harder, and I submit them here in
case they are easy to fix or implement. I dont know if those behaviors are
normal or bugs.
6-ALSO: if anybody has some write up of how to use the "RASTER MAP CALCULATOR"
in the GRASS tools, I will very much appreciate it. I haven't got it to work.
It does not see the rasters I have open, for example...
Thanks!, Maria F.
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