The analysis of whether x I. y can give unreasonable results when x is not sorted is not trivial. For the small cost of sorting x I wonder why you don't just go ahead and sort it.
----- Original Message ----- From: Cliff Reiter <[EMAIL PROTECTED]> Date: Thursday, April 3, 2008 6:25 Subject: Interval Index: was Re: [Jgeneral] Transitive Closure and Line Wrap To: General forum <[email protected]> > I have been fairly routinely using Interval Index x I. y with > "almost ordered" lists x. These are lists of a few thousand > scalars where 98% of the steps are increasing and the > deceases are tiny. I only need an index near the value y > and have no need of a particular choice of index. I > get visual feedback on all the results and have never > felt the need to chose anything other than x I. y. > > Am I a foolish old man? > > Roger Hui wrote: > > Interval Index is just finding the index of an item in > > a sorted list. Not really all that novel (binary search, > > etc.) In 1987 I did not have it as a primitive and > > solved the problem with one application of the monad /: . > > > ... ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
