There's no reason to recur at all: (defn factorial [n] (reduce * (range 1 (inc n))))
On Thu, Jul 15, 2010 at 9:49 AM, Frederick Polgardy <f...@polgardy.com>wrote: > You don't need to recur to another function, just recur to a loop: > > (defn factorial [n] > (loop [x n acc 1] > (if (zero? x) acc (recur (dec x) (* acc x))))) > > (println (factorial 5)) > > -- > Science answers questions; philosophy questions answers. > > On Jul 15, 2010, at 6:38 AM, Brisance wrote: > > > Here's a factorial function as found in the WikiBook "Learning > > Clojure" <http://en.wikibooks.org/wiki/Learning_Clojure>: > > > > (defn factorial [n] > > (defn fac [n acc] > > (if (zero? n) > > acc > > (recur (- n 1) (* acc n)))) ; recursive call to fac, but reuses > > the stack; n will be (- n 1), and acc will be (* acc n) > > (fac n 1)) > > > > Question: how would I go about writing idiomatic Clojure to return > > factorials of n, for large values of n. e.g. 1e6 or more? Preferably > > without having to create another function. > > > > Thanks in advance for any insight. > > > > -- > > You received this message because you are subscribed to the Google > > Groups "Clojure" group. > > To post to this group, send email to clojure@googlegroups.com > > Note that posts from new members are moderated - please be patient with > your first post. > > To unsubscribe from this group, send email to > > clojure+unsubscr...@googlegroups.com<clojure%2bunsubscr...@googlegroups.com> > > For more options, visit this group at > > http://groups.google.com/group/clojure?hl=en > > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with > your first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com<clojure%2bunsubscr...@googlegroups.com> > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
