I have a question, I am trying to calculate a radius between two latitude and longitude points on the Google map.
I understand the coding part, but I do not understand the mathematical side to it. I would appericate if you guys can give me some guidance to this.
Here is the code, maybe you can get some understanding on what I am trying to achive
( 3959 * acos( cos( radians(in_end_lat) ) * cos( radians( lat ) ) * cos( radians( lng ) - radians(in_end_lng) ) + sin( radians(in_end_lat) ) * sin( radians( lat ) ) ) )
Cheers!