[Closed] Spline Math Problem

Hi, I was wondering how I’d go about doing something like this…

I got a Line (B-Spline I think – the smooth one without handles) with three points – Start End and Middle.

Now I want to know at what percent of the line the middle point is from start to finish. Is there somthing inbuilt in max where I can find the length of a line segment? (much like curveLength() for the whole line) Or am I going to need to use the spline math behind the curve in order to do this?

Thanks in advance for your help.