Thanks for all the excellent, concise advice! For code and idiomatic improvements, from these messages I have the following
- For order 1 access use vector - Use subvectors for efficient partitioning - Case/compare is concise, powerful and readable - Use seq idiom to proceed or return nil - Two spaces for indentation - Indentation: parameters at same level, flow control at next level - Line up trailing parens - Dash, not underscore - =, unless data is integer and we have performance measurements that demand == - inc more idiomatic than (+ number 1) Awesome advice, getting into this has been totally great. Brody On Thu, Oct 21, 2010 at 11:50 AM, Jürgen Hötzel <juer...@hoetzel.info>wrote: > 2010/10/21 Brody Berg <brodyb...@gmail.com>: > > (defn binary-search > > "Search sorted list for target using binary search technique" > > Binary search is only useful on indexed data types like Clojure Vectors. > > > ([m_list target] > > (if (empty? m_list) > > false > > (binary-search m_list 0 (- (count m_list) 1) target)) > > ) > > ([m_list m_left m_right target] > > Because Vectors are persistent you can create Sub-Vectors instead of > keeping tracking offsets. > > > (let [gap (- m_right m_left)] > > (if (>= 0 gap) > > (if (== (nth m_list m_left) target) > > (nth m_list m_left) > > false > > No need for explicit false. > > Using case/compare you can also replace multiple tests by a single > comparison and constant time lookup: > > (defn binary-search [v x] > (if (seq v) > (let [half (quot (count v) 2) > middle (v half)] > (case (compare middle x) > -1 (recur (subvec v (inc half)) x) > 1 (recur (subvec v 0 half) x) > true)))) > > Jürgen > > -- > 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
