this code working but when select one text only
(defun c:rt (/ sset n inc ss dxfdata old-dxf new-dxf dxfdata)
(while T
(if (setq sset (ssget "_:L" '((0 . "TEXT,MTEXT"))))
(progn
(repeat (setq n (sslength sset))
(setq inc 0)
(setq ss (ssname sset inc))
(setq dxfdata (entget ss))
(setq old-dxf (assoc 1 dxfdata))
(setq new-dxf (cons 1 (itoa (round (distof (cdr old-dxf)) 5))))
(setq dxfdata (subst new-dxf old-dxf dxfdata))
(entmod dxfdata)
(setq inc (1+ inc))
))
)
(princ "\n Type rt to Invoke")
(princ)
)
)