Is there existing function for great-circle least-square fit?

Is there existing function to fit a great circle to points on a sphere?

[John D'Errico]

Did you bother to look on the file exchange? Why not? Why would our doing a search be any better than your search?

[Ray Lee]

I had searched in the File Exchange. There are lots of functions for LS fit, but none is designed for fitting a great circle on a sphere. I also googled. The closest topic is a post on the matplotlib forum but no solution.