Incrementing pick points alphabetically

[smaher12]

I know how to increment pick points numerically (see below). How is it done alphabetically?

(defun C:test (/ pt# pt)
   (setq pt# (getint "\nEnter number: "))
     (while
       (setq pt (getpoint "\nSpecify point: " ))
         (if (/= pt nil)
           (progn
             (command "TEXT" "M" pt "" "" pt#)
             (setq pt# (1+ pt#))
           )
         )
      )
 (princ)
)

[Kent1Cooper]

---

@smaher12 wrote:

I know how to increment pick points numerically (see below). How is it done alphabetically?

.... 

---

You need to use the (ascii) and (chr) functions to give integer equivalents to letters so that you can increment them upward, for example:
 

(defun C:test (/ ltr asc pt)
  (setq
    ltr (getstring "\nEnter starting letter: ")
    asc (ascii ltr)
  )
  (while
    (setq pt (getpoint "\nSpecify point: " ))
    (progn
      (command "TEXT" "M" pt "" "" (chr asc))
      (setq asc (1+ asc))
    )
  )
  (princ)
)

Consider whether you need to make it more sophisticated, for instance, if the User picks enough points to go past Z [or z], it will move into punctuation characters, but you could have it go into double letters instead.  I think there are threads on this Forum that include ways to do that.  You could also have it check whether the User entered a single letter, or let them start with a double letter, and some other things.

[smaher12]

Thank you Kent. I am looking at the following post (message 4) to consider what to do after Z or z.

http://forums.autodesk.com/t5/Visual-LISP-AutoLISP-and-General/Auto-Increment-Letter/td-p/2325302

[Lee_Mac]

You may also be interested in my Increment Alpha & Alpha++ functions as part of my set of Column Reference Functions - that page also provides examples of how to call the functions with the required arguments.

I hope this helps!