[GRASS5] v.to.db 2 new features compactness and perimeter

[Wolf Bergenheim]

Radim Blazek wrote:
> On 11/10/05, Wolf Bergenheim <wolf at bergenheim.net> wrote:
> 
>>Heh. defenately not... I use Vect_line_length() to calculate the length.
>>perhaps the the fix should go in here? perhaps an additional parameter
>>or a new fun Vect_line_length_meters(). I guess that the area is ok? or
>>does it have a unit of square degrees? (;
> 
> 
> There is Vect_line_geodesic_length but it should only be used with -g flag.
> 

How about calculating the distance normally (the circumference, and then 
converting the angular distance to metric, by using:
distance in meters = angle * pi * radius (which is what? 6365 km? Is 
there any way of getting the radius of the projection?)

How can I deterimin if the projection is LL?

--W

-- 

<:3 )---- Wolf Bergenheim ----( 8:>