> I had a crack at it in Lisp. My version doesn't work - but of greater
> concern to me is that it doesn't appear nearly as compact as the C
> version. Anyway, here's my Lisp code (no prizes for guessing that I'm a
> noob to Lisp):
Lot's of things you can write more compact.
But compact is not always the best way to
write source. For me the most important
criteria is that I can return to some source
after, say, a year absence and everything
is clear and readable again.
>
> (defconstant delta 2654435769 ) ; delta= 0x9E3779B9
(defconstant +delta+ #x9E3779B9)
> (defun floorn (n) (nth-value 0 (floor n)))
is above used?
> (defun >> (val num-bytes)
> "Right-shift positive integer val by num-bytes"
> (let* (t1 t2)
> (setf t1 (expt 2 num-bytes))
> (setf t2 (/ val t1))
> (floor t2)))
(defun >> (val num-bytes)
"Right-shift positive integer val by num-bytes"
(floor (/ val (expt 2 num-bytes))))
> (defun transform (v1 v2 v3 v4)
> (let (t1 t2 t3)
> (setf t1 (<<4 v1))
> (setf t2 (expt v2 v1))
> (setf t3 (expt v3 (>> v2 5)))
> (+ t1 t2 t3 v4)))
>
(defun transform (v1 v2 v3 v4)
(+ (<<4 v1)
(expt v2 v1)
(expt v3 (>> v2 5))
v4))
and so on...
--
http://mail.python.org/mailman/listinfo/python-list
