Hi everybody,

First thing I want to apologize if something that I wrote sounds strange. Im spanish and my english is not as good as it should be=P.
Im learling little by little autolisp things, mostly strugling through examples, codes, etc... many of them from this forum so I thank you a lot ^_^.

At this moment I'm developing a routine that breaks/trims walls in order to insert doors or windows, and, after looking for it a few days, I would like to know if there's a way to use a number that users input on the command line (in a getpoint) without getting an error.,... wich is that happends everytime =/.

Code:
;; HOLE-O-MaTIC 2000
;;  by Arturo Blanco UreƱa. 2013
;; Breaks "walls" in order to insert windows or doors
;; Based initialy on code from Pavel Chour http://klobouk.fsv.cvut.cz/~chour/Lisp/Chapter%206.htm

(defun error1 (errmsg)
   (command "_undo" "_end")
   (setvar "CMDECHO" 1)
   (setvar "OSMODE" osmodevar)
   (setq *error* temperr)
   (prompt "\nAchtung!!! Verboten!!! Error!!!\n")
  (princ)
  )

(defun c:holes(/ );P1a P2a P1 P2 P3 P4 A1 A2)
  (setq osmodevar 	(getvar 'OSMODE)
	temperr   	*error*
	*error*   	error1
  	)
  (if (not ancho) (setq ancho 1.50))
  (setq Tancho (rtos ancho)
	P1 "Width"
	)
  (setvar "CMDECHO" 0)
  (command "_undo" "_begin")
  (setvar "osmode" 512)
  
  ;I'm using this structure in order to go back to the menu so I can change my mind several times.
  ;Don't know if there's a better way =P. 
  ;---
  (while (= P1 "Width")
   (initget 128)
   (setq P1 (getpoint (strcat "\nSelect Point or [Center/Width]<" Tancho ">:")))
   (cond ((numberp P1)	(setq ancho P1)			;trying to recognice P1 as a number but always goes on error =/
	  		(setq Tancho (rtos ancho))
	  );cond1
     	 ((= P1 "Width")(setvar "osmode" 35)		
	  		(setq ancho (getdist "\nWidth of the Door/window?:"))
 			(setq Tancho (rtos ancho))
	  );cond2
    );end cond
   );end while
  ;---
  
  (cond ((= P1 "Center") (setvar "OSMODE" 518) 		;If the user want to break from the center of the window.
	 		(setq P1a (getpoint (strcat "\nSelect center <" Tancho ">:")))
	 		(setvar "OSMODE" 128)
			(setq P2a (getpoint P1a "\nSelect the other side of the wall:")
			      A1 (angle P1a P2a)
			      A2 (+ (* pi 1.5) A1)
			      P1 (polar P1a A2 (* ancho 0.5))
			      P3 (polar P1a A2 (* ancho -0.5))
			      P2 (polar P2a A2 (* ancho 0.5))
			      P4 (polar P2a A2 (* ancho -0.5))
			      )
	 );end cond1
	  (T	 (setvar "osmode" 128) 			;if he/she wants to start from one side
		 (setq P2 (getpoint P1 "\nSelect the other side of the wall:"))
		 (setvar "osmode" 512)
	  	 (setq	A1 (angle P1 P2)
			A2 (+ (* pi 1.5) A1)
			P3 (polar P1 A2 ancho)
			P4 (polar P2 A2 ancho)
			P1a (polar P1 A2 (* ancho 0.5))
			P2a (polar P2 A2 (* ancho 0.5))
	  		)
	   );end else
	);end cond
  
  (setvar "osmode" 512)
  (command	"_break" P1 P3
            	"_break" P2 P4 
    		"_line" P1 P2 "")
  (setq L1 (entlast))
  (command	"_line" P3 P4 "")
  (setq L2 (entlast))
  
  ;I add this in order to trim extra lines in the middle of the wall.
  (command "_trim" L1 L2 "" "B" P1a P2a "" "")
  
  (command "_undo" "_end")
  (setvar "CMDECHO" 1)
  (setvar "OSMODE" osmodevar)
  (setq *error* temperr)
  (princ)
);end
As you see You can enter the "Width" to give it, but I would like to simply write down a number when asking for a point, recognize that is a number and use it as the value of the variant. If a point is entered, then continue normally.

Im a bit shy and its the first time i post a code. I have used several pieces of code from others to arrange the error handling/undo and its originally based on one tutorial from Pavel Chour, so I dont know if its right that I give permission or not to use it, or even its worth it (the trim still fails and i dont really get why ) but If anyone want to use it feel free.

Any tips critics and opinions are welcome also