Dan Bron wrote: > Henry wrote: >> If you pick one possible result, that's pretty arbitrary and >> not interesting to me. > > Do you object to %: then? How about | ? And ^. ? ....
The issue is that a function f has an inverse only if it is 1-1. If it is not 1-1 and you still want an inverse, you have to restrict the domain. For example, if f=:*: , we restrict to [0,infinity). If f=:sin , we restrict to [-pi/2,pi/2]. The problem is that for a general polynomial, there is no obviously useful systematic restriction. Best wishes, John ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
