[R] Convex hull line coordinates..

Barry Rowlingson B.Rowlingson at lancaster.ac.uk
Mon Mar 21 18:56:56 CET 2005

Romain Francois wrote:
> Hello,
> I'm not sure i got your question right, but i think the whole point is 
> to find the equation of a line which passes by two points
> See ?lm

  Or see a basic geometry book, where you will find a formula such as:

  (x-x1)/(y-y1) = (x2-x1)/(y2-y1)

for the equation of a line passing through (x1,y1) and (x2,y2).

Just watch out for y2==y1 and the inevitable division by zero. Might be 
better to ask what you want the line for in order to find a 
representation that better suits your need - a single point and slope, 


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