The centroid divides the segment joining the circumcentre and the orthocentre in the ratio 2:1. The centroid is the average of the triangle's vertices, and if there is a similar neat formula for the circumcentre, then the orthocentre would be calculable from that.
> I need to calculate the orthocentre of a triangle. The only info > available to me are the coordinates of the endpoints of the triangle. > I would like to use matlab to calculate the orthocentre. > Any ideas???