[GRASS-user] Lambert Conformal Conic location

[Roberto Antolin]

Hola Miriam,

Miriam ha scritto:
> I'm triying to define a new location for a volume with this data:
> 
> Lambert Conformal projection:
> 	Standard Latitude 1: 60.000000
> 	Standard Latitude 2: 30.000000
> 	North/South Pole Row: -61.842026
> 	North/South Pole Column: 19.503059
> 	Central Longitude: 85.000000
> 	Column Increment: 90.000008 km
> 
> In 6.3-cvs.
> 
> It's a grid over Florida of 34 rows and 40 cols.
> 
> I'm selecting this option on the shell-script menu:
> 
> D
> 'Florida location'
> projection: lcc
> datum: nad27
> parameters: 1
> Central Parallel:36N
> Standart Parallel 1: 60N
> Standart Parallel 2: 30N
> Central meridian: 85W
> False easting: -61.84
> False northing: 19.50
> 
> 
> After I make the input above  that i don't know if it's correct, i try a
> region from 40N 0S 0W 34E, 1 res n-s, 1 res w-e (because I know previously
> that the grid is 34x40), 

Maybe I'm wrong, since I've never worked before with this kind of 
projections within GRASS, but the bounding box that you have just set 
begins at O°West and ends at 34°East. However, the central meridian for 
your data is 85°West. So I suppose your data is around this meridian, 
not between 0°-30°.

> I can't calculate the
> grid dimensions for the region which adjusts my map... i can't see it.

Try:
# g.region rast=your_map -g

and you will set the region to fix your map and also you will see what's 
really your data's bounding box. After that, you should be able to 
visualize your map:
# d.mon x0
# d.rast "your_map"

> Anyone can suggest a solution? Maybe I don't understand the region
> concept... what are the units which I define the region: meters, pixels,
> degrees...? 

The region units can be seen in the "YOUR_LOCATION/PERMANENT/PROJ_UNIT" file

I hope it will help.
Salu2,
Roberto.

Ps: También puedes enviarlo al lista en español, así generamos algo de 
tráfico en la lista ;)

-- 
Roberto Antolín Sánchez
Politecnico di Milano – Polo Regionale di Como
(Laboratorio di Geomatica V2.8)
Via Valleggio, 11 – 22100 Como, Italy
tel: +39 031 332 7533 || fax: +39 031 332 7519
email: roberto.antolin at polimi.it