CGAL users discussion list

[Wolfgang Aigner <>]

On Sunday 28 October 2007 12:15, 

 wrote:
> Hi,
> How can I tangent a line on a circle?
>
> thanks,

Now this is a question, which requires further information:

first of all: do you have any fix point, this tangent shall contain?
If yes, is this point on the circles boundary?
If yes, is this point a rational / MP_Float, or is it a Root_of_2 type?

If a point outside the circle is given, which shall be on the line, there
may arise some problems, as well if a Root_of_2 point on the
circle is given as point of tangency. It is not possible (yet?) to define
an exact line by the use of algebraic Root_of_2 points.

So what do you really need?