RE: Draw a line through 2 points

[Ted Harding]

On 15-May-04 Sue Stones wrote:
> How do I draw a line through 2 points.  Not just between the points
> but going off the graph on either side?
> 
> sue

You can do it by specifying two other points to define a line which
includes the two given points.

e.g. (adjust t1, t2 to your taste; the values below extend the line
between p1 and p2 to either side by 10 times the distance between
p1 and p2):

  p1=[x1;y1]; p2=[x2;y2];
  t1=(-10); t2=(+10);
  P1=p1 + t1*(p2-p1) ; P2=p2 + t2*(p2-p1);

Now draw a line from P1 to P2 (when t1=0 and t2=0 you get the original
points p1 and p2).

Hope this helps,
Ted.


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E-Mail: (Ted Harding) <address@hidden>
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Date: 15-May-04                                       Time: 15:57:30
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