New Lisp Routine help

[Anonymous]

How do I create a lisp routine that draws a circle, then inscribes an equilateral triangle and circumscribes a square while only prompting the user to chose a center point and radius for the circle?  I am having trouble figuring out the lisp routine. 

[Shneuph]

Maybe post what you have got so far and we can recommend changes?

[Anonymous]

this is all I have 

[Ranjit_Singh · Accepted solution]

It's pretty simple using native Autocad commands, if I understand you correct

(defun c:somefunc  (/ cen rad)
 (command "._circle" (setq cen (getpoint "\nSpecify center point: ")) pause)
 (command "._polygon" 3 "_non" cen "_i" "_non" (setq rad (cdr (assoc 40 (entget (entlast))))) "._polygon" 4 "_non" cen "_c" "_non" rad))

[Anonymous]

This is great! That's exactly what I was looking for. Thank you, your help is very much appreciated. 

[Kent1Cooper]

If you do this often, I would suggest a little drawing of that with a 1-unit radius in the Circle.  Then you can just Insert it, with the scale factors being the desired radius -- a one-command rather than three-command process.