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jonnylane
Apr23-03, 06:25 AM
Hi there,

I have a bit of a problem for you. I have recently had to write a program to compute the centroid (centre of area) of a 2d shape. I used a many-point weighted triangle method. The shapes themselves are ROI's of anatomical features on SPECT and MRI scans.

Im writing up my dissertation and im trying to come up with a scientific definition of a centroid. Ive tried "point of rotation at which ACW moment = CW moment = 0,and a few others, but this doesnt sound right in the purely mathematical context.

any ideas?
thanks

dg
Apr25-03, 12:39 AM
The centroid is simply more known to physicist as "center of mass"...

Anyway this will help: http://mathworld.wolfram.com/GeometricCentroid.html

If not ask again... ;) Dario