;; | ---------------------------------------------------------------------------
;; | LI_Collapse
;; | ---------------------------------------------------------------------------
;; | Function : Collapses 'n' number of items from a list and returns a sub-list
;; |            of collapsed list.
;; | Argument : 'Lst'    - The list to collapse
;; |            'num'    - Number of items to form a sub-list
;; | Returns  : The newly created list
;; | Updated  : October 22, 2001
;; | e-mail   : rakesh.rao@4d-technologies.com 
;; | Web      : www.4d-technologies.com
;; | ---------------------------------------------------------------------------


(defun LI_Collapse( Lst num / len CLst Lst1 Idx )

(setq
	CLst '()
	len (length Lst)
)
(if (and
		(> num 0)
		(zerop (rem len num))
	)
(progn
	(setq
		Idx 0
		CLst '()
	)
	(repeat (/ len num)
		(setq Lst1 '())
		(repeat num
			(setq
				Lst1 (cons (nth Idx Lst) Lst1)
				Idx (1+ Idx)
			)
		)
		(setq
			Lst1 (reverse Lst1)
			CLst (cons Lst1 CLst)
		)
	)
	(setq CLst (reverse CLst))
))
CLst
)