I'm interested in J solutions of an application of Haskell's monadic mapping:
mapM (\x -> [x-1, x+1]) [10,20,30] [[9,19,29],[9,19,31],[9,21,29],[9,21,31], [11,19,29],[11,19,31],[11,21,29],[11,21,31] Here's my first shot: ((-"1) _1^#:@i.@(2^#)) 10 20 30 Or in case of 3 functions: ([`(>:@[)`(<:@[)@.]"0"(1) 3 #.^:_1 i.@(3^#)) 10 20 30 The number of elements of the result is equal to the <number of functions>^<list length> =@@i ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
