[GRASSLIST:6885] Re: beginner's question

[Rahul Chopra]

Thanks for your reply Ian. I actually figured out the script for multiple 
imports of raster files. It goes a little like this

for file in *.tif
do
r.in.gdal in=$file out=$file
done

As for the UTM lat-long conversion, since the data is in UTM coordinates, 
I'd like to create my grass location in it too and thus the struggle for 
converting lat long to UTM. What gdal command do you use?

Rahul

----- Original Message ----- 
From: "Ian W. Macmillan" <ian_macmillan at umail.ucsb.edu>
To: "Rahul Chopra" <rchopra at uchicago.edu>
Cc: "GRASS Users list" <grasslist at baylor.edu>
Sent: Wednesday, May 25, 2005 2:13 PM
Subject: Re: [GRASSLIST:6882] beginner's question


> Rahul,
> Short answers follow, but hopefully they might point you in the right 
> direction.
>
>
> Quoting Rahul Chopra <rchopra at uchicago.edu>:
>> Hello all,
>>
>> Am new to the mailing list and have a couple of novice like questions.
>>
>> 1. I have downloaded several Landsat ETM+ files which I wish to import 
>> into
>> my GRASS location using r.in.gdal. Could someone provide some help with 
>> what
>> the script might have to look like in order to import multiple tif files
>> into this location?
> SORRY NO HELP FOR YOU HERE.  I JUST USUALLY RUN R.IN.GDAL MULTIPLE TIMES
>
>
>> 2. In order to apply radiometric corrections I ran grep BIAS dataset.met 
>> and
>> get the message CORRECTION_METHOD_BIAS = "IC.  Does that mean that the
>> radiometric corrections have already been applied? In the metadata file 
>> from
>> GLCF's website it does say END_GROUP = CORRECTIONS_APPLIED
> MOST GLCF FILES ARE ALREADY CORRECTED AND DON'T REALLY REQUIRE ANY POST
> PROCESSING
>
>
>> 3. When I  patch, say band 4 of  2 scenes I find a distinct difference in
>> the intensity/brightness of the 2 scenes.  The sun elevation and sun 
>> azimuth
>> are different in these 2 scenes? Is that the reason for difference in
>> brightness? If so, how does one change the sun elevation and azimuth for 
>> one
>> scene?
> YOU CAN'T CHANGE THE SUN ELEVATION AND AZIMUTH OF THE SHOT, IT IS FIXED 
> WHEN THE
> IMAGE WAS TAKEN.  YOU CAN TRY TO FIND DIFFERENT LANDSAT IMAGES FROM 
> DIFFERENT
> TIMES THAT MIGHT MATCH, BUT IT RARELY WORKS OUT THAT YOU CAN FIND THAT.
>
>
>> 4. One final question-- is there a program which accurately converts
>> latitude longitude into UTM coordinates?
>
> GRASS DOES THIS QUITE WELL (V.PROJ, R.PROJ) OR YOU CAN USE GDAL.
>
> G'luck
> -Ian
>