Trilateration using 3 latitude and longitude points, and 3 distances
- by nohat
There exists an unknown target location (latitude and longitude co-ordinates). I have 3 latitude and longitude co-ordinate pairs and for each pair a distance in kilometers to the target location. How can I calculate the co-ordinates of the target location?
For example, say I have the following data points
37.418436,-121.963477 0.265710701754km
37.417243,-121.961889 0.234592423446km
37.418692,-121.960194 0.0548954278262km
What I'd like is what would the guts of the function that takes that as input and returns 37.417959,-121.961954 as output look like?
I understand how to calculate the distance between two points, from http://www.movable-type.co.uk/scripts/latlong.html I understand the general principle that with three circles you get exactly one point of overlap. What I'm hazy on is the math needed to calculate that point with this input.
