I was initially surprised by the big differences in performance between different formulations of the sum of the quotients
tstdata=: _2 */\ 1+2*i.1000000 50 timespacex '+/ 8 % tstdata' 0.00206915 4.19581e6 50 timespacex '8 +/@:% tstdata' 0.0686648 1792 The first is up to 113 times faster (depending on platform and J version), the 2nd is over 2000 times leaner. I see similar differences back to J602. I think this surprised me because I am usually comparing the sum of products. In that case I guess the special code for +/@:* hides the "usual" difference 50 timespacex '+/ 8 * tstdata' 0.00193723 4.19581e6 50 timespacex '8 +/@:* tstdata' 0.00042151 1664 It does make we wonder if we can't do better for quotient? I imagine the answer is yes but whether it is worth it depends on how often it is used. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
