Re: sorting by comparing two nodes

> Yes, that's the point. 

but aside from the fact that the syntax doesn't allow it, if the
comparison function for two points is not transitive, the answer isn't
well specified (what does it mean to sort in that case?)

> But computing angles is based on slow inaccurate trigonometric functions.

You only need to do one division don't you? That gives the tangent
which is enough once you know which quadrant you are in. You don't need
arctan if you only need to order.

David

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