Hi Nikos:<div>Thanks for your detailed reply!</div><div>And I know the reason of the problem now.</div><div>However as what you said,I should create a new location and mapset if necessary,it does not work.</div><div>I create two folders nLocation/nmapset and create a wind file in the nmapset dir,however when I run the grass gui,I also can not seclect the new location to enter. It throw the error message:the selection location [nlocation ]is not valide. Is the procedure I create the new location is wrong? I followed the maual</div>
<div><br></div><div>maven</div><div><br></div><div><div class="gmail_quote">2009/6/11 Nikos Alexandris <span dir="ltr"><<a href="mailto:nikos.alexandris@felis.uni-freiburg.de">nikos.alexandris@felis.uni-freiburg.de</a>></span><br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><br>
maven apache:<br>
<div class="im">> When import some raster data to grass,I use the following cmd:<br>
> 1) g.region -d<br>
<br>
</div>This sets to the "default" region which one previously needs to define,<br>
i.e. needs to create with "g.region -s". Please check the manual of<br>
g.region.<br>
<div class="im"><br>
<br>
> 2) r.in.gdal input=D:/test.TIF output=testTT --overwrite<br>
<br>
> I got the error message as following:<br>
> ---------------<br>
> Projection of dataset does not appear to match current location.<br>
>Location PROJ_INFO is:<br>
>name: UTM<br>
>datum: nad27<br>
</div>[...]<br>
<div class="im">> Import dataset PROJ_INFO is:<br>
> cellhd.proj = 0 (unreferenced/unknown)<br>
> ------------------------<br>
<br>
</div>That's seems normal. Your test.TIF either isn't georeferenced or it lost<br>
its geotags at some point (after editing with non-GIS tool perhaps?).<br>
<div class="im"><br>
> 3) change the cmd to " r.in.gdal -o input=D:/test.TIF output=testTT<br>
> --overwrite " I know this override the projection,however I am not<br>
> sure the potential effect to the data.<br>
<br>
</div>You should use that only if you _know_ that your test.TIF data are<br>
projected in the system that your grass-location is defined (e.g.<br>
"datum: nad27" as one can see in the error message above). If your data<br>
(test.TIF) are projected in another proj. system expect errors.<br>
<div class="im"><br>
<br>
> Now the tiff is imported,and I got testTT.bule testTT.red<br>
> testTT.green, then I open them can only see blank. So I wonder it is<br>
> caused by the projection or location,I use the spanish data as the<br>
> default location , and I tried to create new location and mapset but<br>
> never success...<br>
<br>
<br>
</div>So, given that test.TIF is in "UTM, datum: nad27" then you need to:<br>
1. import with r.in.gdal -o (as you already did).<br>
2. g.region rast=testTT.blue<br>
3. view your data<br>
<br>
If the test.TIF data are projected in another system you need to:<br>
1. find out which is that projection system<br>
2. use some gdal tools to assign the proj. information in the test.TIF<br>
file<br>
3. define a "new" grass-location based on the projection information of<br>
the test.TIF data<br>
4. import with r.in.gdal (without the use of "-o" flag)<br>
5. g.region rast=OneOfTheImportedBands<br>
6. view, process, etc.<br>
<br>
<br>
Greetings, Nikos<br>
<br>
<br>
<br>
</blockquote></div><br></div>