This LISP routine is great for when you place a dimension and forgot to dimension some element in your drawing.

Here’s how:

• SPLITDIMs <enter> to start
• Select the dimension that you need to split.
• Select the object where you’d like to split the dimension from.

(defun c:LegLengthMod ( / ss dimobjs)
;; codehimbelonga KerryBrown@theSwamp 2010.05.28
(vl-load-com)
(if (and (setq ss (ssget '((0 . "DIMENSION"))))
(setq dimobjs (mapcar 'vlax-ename->vla-object
(vl-remove-if 'listp (mapcar 'cadr (ssnamex ss)))
)
)
)
(foreach dim dimobjs
(vla-put-extlinefixedlensuppress dim :vlax-true)
(vla-put-extlinefixedlen dim (* 2 (vla-get-textheight dim)))
)
)
(princ)
)
(defun c:SplitDims (/ sel newpt ent edata elist)
;; codehimbelonga KerryBrown@theSwamp 2010.05.28
(if (and (setq sel (entsel "\nSelect Dimension to Split."))
(setq newpt (getpoint "\Select new Dim Point"))
)
(progn (setq ent (car sel)
edata (entget ent)
elist (vl-remove-if
'(lambda (pair)
(member (car pair)
(list -1 2 5 102 310 300 330 331 340 350 360 410)
)
)
edata
)
)
(entmod (subst (cons 14 newpt) (assoc 14 elist) edata))
(entmakex (subst (cons 13 newpt) (assoc 13 elist) elist))
)
)
(princ)
)