Hello list members,
this is the first time that I write to this list. I'm a system
administrator at a hungarian company, and I'm struggling to change the
workstation's operating system to Linux. One of the biggest chalenge is
to find a replacement for Golden Software's Surfer software. I found
Grass, and I think it could be a good alternative, but it seems a little
bit harder to use.
Another problem is that our engineers don't want to use Linux at all, so
it is up to me to find alternatives for their softwares.
As far as I know, our engineers use Surfer mainly to make isolined maps
from xyz coordinates.
So my first question is that if I have a simple text file that contains
x,y,z coordinates, and I would like to make an iso surface from it, how
should I do it?
I know that it is impossible to learn to use Grass via mailing-list, but
I would like to get started to use it to be able to demonstrate it's
possibilities to our engineers.
Thank you for your help in advance,
Istvan
Hi,
1. import ASCII data in to vector file (v.in.ascii);
2. create surface from imported data with v.surf.rst;
3. draw contours usin r.contour.
Most hardest part - how to find best RST tuning parameters.
Bonus - You can visualize surface from 2. step with nviz 
Read on manual and
http://www.ing.unitn.it/~grass/conferences/GRASS2002/proceedings/proceedings/pdfs/Cebecauer_Tomas.pdf
wbr,
Maris.
On 5/24/05, Stefan Istvan <stefi@geohidroterv.hu> wrote:
Hello list members,
this is the first time that I write to this list. I'm a system
administrator at a hungarian company, and I'm struggling to change the
workstation's operating system to Linux. One of the biggest chalenge is
to find a replacement for Golden Software's Surfer software. I found
Grass, and I think it could be a good alternative, but it seems a little
bit harder to use.
Another problem is that our engineers don't want to use Linux at all, so
it is up to me to find alternatives for their softwares.
As far as I know, our engineers use Surfer mainly to make isolined maps
from xyz coordinates.
So my first question is that if I have a simple text file that contains
x,y,z coordinates, and I would like to make an iso surface from it, how
should I do it?
I know that it is impossible to learn to use Grass via mailing-list, but
I would like to get started to use it to be able to demonstrate it's
possibilities to our engineers.
Thank you for your help in advance,
Istvan
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?
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
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?
4. One final question-- is there a program which accurately converts latitude longitude into UTM coordinates?
I would appreciate it if anyone could take the time to answer these queries.
Thanks
Rahul
Rahul,
Short answers follow, but hopefully they might point you in the right direction.
Quoting Rahul Chopra <rchopra@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
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@umail.ucsb.edu>
To: "Rahul Chopra" <rchopra@uchicago.edu>
Cc: "GRASS Users list" <grasslist@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@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
On Wed, May 25, 2005 21:29, Rahul Chopra said:
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?
Why do you need to convert from lat-long ?
You have two choices:
1) if you know your datum settings (projection and ellipsoid) than you create
a new location with these settings and directly import your data there
2) if you don't know your datum settings, than in any existing location
(whatever its datum), run r.in.gdal with the location= option for one raster
to have it create a new location with the appropriate settings. Then you can
run your above script with the '-e' flag for gdal to extend the location as
needed for the different raster files.
Moritz
Rahul
----- Original Message -----
From: "Ian W. Macmillan" <ian_macmillan@umail.ucsb.edu>
To: "Rahul Chopra" <rchopra@uchicago.edu>
Cc: "GRASS Users list" <grasslist@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@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
Thanks Moritz. It now appears embarassingly obvious.
----- Original Message ----- From: "Moritz Lennert" <mlennert@club.worldonline.be>
To: "Rahul Chopra" <rchopra@uchicago.edu>
Cc: "Ian W. Macmillan" <ian_macmillan@umail.ucsb.edu>; "GRASS Users list" <grasslist@baylor.edu>
Sent: Wednesday, May 25, 2005 3:21 PM
Subject: Re: [GRASSLIST:6885] Re: beginner's question
On Wed, May 25, 2005 21:29, Rahul Chopra said:
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?
Why do you need to convert from lat-long ?
You have two choices:
1) if you know your datum settings (projection and ellipsoid) than you create
a new location with these settings and directly import your data there
2) if you don't know your datum settings, than in any existing location
(whatever its datum), run r.in.gdal with the location= option for one raster
to have it create a new location with the appropriate settings. Then you can
run your above script with the '-e' flag for gdal to extend the location as
needed for the different raster files.
Moritz
Rahul
----- Original Message -----
From: "Ian W. Macmillan" <ian_macmillan@umail.ucsb.edu>
To: "Rahul Chopra" <rchopra@uchicago.edu>
Cc: "GRASS Users list" <grasslist@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@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