>I am trying to smooth some intersecting lines, and for that I think I need the formula of a circle that is tangent to this two intersecting lines; now, I realize that there will be infinite circles matching this, but I can or would like to <g> specify the tangent points (the points where the circle touches each line), but I am googling for this formula without much success, and all the links that look promising get blocked by the internet filter, so, does anyone know how can I solve this problem?
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>TIA
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>Hugo

Let as assume you know tangent lines and coordinates of tangent points on them:
y=ax+b, (e,f)
y=cx+d, (g,h)

Then you draw the perpendicular lines
y = -x/a + f + e/a
y = -x/c + h + g/c

Center of the circle is on the intersection of those two perpendicular lines. Its coordinates are:
Cx = (h + g/c - f - e/a)* c* c/(a-c)
Cy = -(Cx)/a + f + e/a

Radius is:

R= sqrt((Cx-e)^2 + (Cy - f)^2)

And formula for circle is:

(y-Cy)^2 + (x - Cx)^2 = R^2

Good Luck