I'm a newbie in grass GIS so I'm sorry, if this question is very simple. Has
anyone any idea how to create a raster map including only the information of
the latitude and longitude of each cell? I want to write a script to compute
the solar elevation angle for a large area and time range and it would be
easier with this map. Can anyone help me? Thank you very much
Do your cells contain some other information (i.e. the variable you want
to create raster for) apart from lat and long?
What format is your lat/long file? text or some sort of a vector?
Do you want to directly convert the values to cells with raster values or
having some interpolation and TINs?
Could you send a small sample of your date?
Cheers
Sab
Dear all,
I'm a newbie in grass GIS so I'm sorry, if this question is very simple.
Has
anyone any idea how to create a raster map including only the information
of
the latitude and longitude of each cell? I want to write a script to
compute
the solar elevation angle for a large area and time range and it would be
easier with this map. Can anyone help me? Thank you very much
No I don't have any other information, lat and long are variables in my
formulas and I want to create a map to make it easier to integrate them in
my script. I want to have cells that contain only lat long as information.
At the moment I don't have any data with the coordinates because I wanted to
know the way to create the map first to decide what sort of data I choose.
But I will look for some data I can get and then write again, thanks for
your reply.
I'm a newbie in grass GIS so I'm sorry, if this question is very simple.
Has anyone any idea how to create a raster map including only the
information of the latitude and longitude of each cell? I want to write a
script to compute the solar elevation angle for a large area and time
range and it would be easier with this map. Can anyone help me? Thank you
very much
Hey,
You can assess the internal variables which r.mapcalc work with by some
specific commands. x() and y() retrieve the coordinate information.
So, after definining your region of calculation with g.region, you can then
do:
r.mapcalc "long=x()"
r.mapcalc "lat=y()"
In this way, you will have two rasters, each of which contains one dimension
of your coordinates. Then you can do calculations with them as you like.