Question Regarding Geometric Operators/Function . . .

On Thu, Aug 29, 2002 at 15:51:13 -0400,
"Peter E. Chen" <pchen3@jhmi.edu> wrote:

Hey Everyone,

Does anyone know if there is a geometric operator/function that will allow
me to determine if a line segment and a point overlap? By overlap I mean
that the point lies on the line segment. I can't seem to do this with the
available geometric operators.

There probably isn't an operator to do this because those types are based
on floating point data and you won't be able to reliably determine this.

Also, can someone explain to me the difference between how postgres defines
overlap and intersect for its geometric operators/functions.

I am not an expert here, but typically an overlap is something that this
testable (and would be true or false), while an intersection is a set
(and would be some geometric object).