Peña wrote:
> Ingo Weiss:
>
> # //JavaScript:
> # dlng = p2_lng - p1_lng
> # dlat = p2_lat - p1_lat
> # a = (sin(dlat/2))^2 + cos(p1_lat) * cos(p2_lat) * (sin(dlon/2))^2
> # c = 2 * atan2( sqrt(a), sqrt(1-a) )
> # distance = R * c (where R is the radius of the Earth)
> # 
> # 
> # #Ruby:
> # dlng = p2_lng - p1_lng
> # dlat = p2_lat - p1_lat
> # a = (Math.sin(dlat/2))**2 + Math.cos(p1_lat) * Math.cos(p2_lat) * 
>   
is dlng a typo, the first formula uses dlon?
> # (Math.sin(dlng/2))**2
> # c = 2 * Math.atan2( Math.sqrt(a), Math.sqrt(1-a) )
> # distance = 6373 * c #(radius of the Earth: 6373km
> # 
> # 
> # Any idea why the Ruby one returns incorrect numbers?
>
> 1) can you post sample running codes on both? (eg what are the values of p2_lang, etc)
>
> 2) do you have test cases? (so we know what to expect)
>
> kind regards -botp
>  
>