Hello

hello
I want to sort GPS waypoints based on both Latitude and longitude and can not figure out how to make this work. Any help would be greatly appreciated.

Image 4 lakes arranged like this geographically (below). Lakes 1 and 2 occupy the same Lats N to S, Lakes 3 and 4 occupy the same Lats N to S, lakes 1 and 3 occupy the same Longs E to W, and lakes 2 and 4 occupy the same Longs E to W.Also, imagine that each lake had 3 waypoints in the exact center E to W and 1 at the Norther most point, 1 in the middle N to S,and 1 at the Southern most point of the lake.