Hi all,
I have a set of 23 Modis NDVI images and I want to sample all images
at specific points (50 points). What I was looking for was something
like v.sample but, instead of generating a new vector with the raster
value, output the values to a text file. I though about using
i.spectral but it does not work on Windows. Another option would be
v.what.rast but I'd have to create a lot of columns in the vector file
first. Is there a quick way to do what I want, or should I make a loop
and use v.what.rast?
Daniel
On Mon, Oct 13, 2008 at 6:38 PM, Daniel Victoria
<daniel.victoria@gmail.com> wrote:
Hi all,
I have a set of 23 Modis NDVI images and I want to sample all images
at specific points (50 points). What I was looking for was something
like v.sample but, instead of generating a new vector with the raster
value, output the values to a text file. I though about using
i.spectral but it does not work on Windows. Another option would be
v.what.rast but I'd have to create a lot of columns in the vector file
first. Is there a quick way to do what I want, or should I make a loop
and use v.what.rast?
I have written such a script for MODIS LST.
- All LST maps have a timestamp (r.timestamp)
- I generate the list of timestamps I want to loop over
with a small script
- then I call r.what
In your case, just encapsulate all with another loop for
the coordinate pairs (for loop over cood pairs saved in
a text file).
I can send you offlist the scripts for LST which require
a bit of adaptation for NDVI.
Perhaps, in Python all might be way easier than in Shell.
Markus
It loops over the given
On Mon, 2008-10-13 at 14:38 -0200, Daniel Victoria wrote:
Hi all,
I have a set of 23 Modis NDVI images and I want to sample all images
at specific points (50 points). What I was looking for was something
like v.sample but, instead of generating a new vector with the raster
value, output the values to a text file. I though about using
i.spectral but it does not work on Windows. Another option would be
v.what.rast but I'd have to create a lot of columns in the vector file
first. Is there a quick way to do what I want, or should I make a loop
and use v.what.rast?
Daniel
Daniel,
this reminds me either starspan or a combination of a MASK in a loop
with r.stats (which I have used for something similar). Or maybe I do
not understand what you need.
Cheers,
Nikos
Silly me! I forgot that I could pipe v.out.ascii to r.what do do
exactly what I wanted!
That's what I get for working with Windows all the time! Man, how I
miss my linux box! Company rules suck (we have to use win)
Daniel
PS - Sorry for the rant
On Mon, Oct 13, 2008 at 3:14 PM, Nikos Alexandris
<nikos.alexandris@felis.uni-freiburg.de> wrote:
On Mon, 2008-10-13 at 14:38 -0200, Daniel Victoria wrote:
Hi all,
I have a set of 23 Modis NDVI images and I want to sample all images
at specific points (50 points). What I was looking for was something
like v.sample but, instead of generating a new vector with the raster
value, output the values to a text file. I though about using
i.spectral but it does not work on Windows. Another option would be
v.what.rast but I'd have to create a lot of columns in the vector file
first. Is there a quick way to do what I want, or should I make a loop
and use v.what.rast?
Daniel
Daniel,
this reminds me either starspan or a combination of a MASK in a loop
with r.stats (which I have used for something similar). Or maybe I do
not understand what you need.
Cheers,
Nikos