Oleg asked:
> Why so complicated?
Because it does more, and is more general. To add value to the thread, as
simple solutions had been previously supplied.
Concretely, if you intend this:
OK> [EMAIL PROTECTED] #: i.&,
to replace this:
DB> E.&>/@:((>. - ,)&:(#@:$) ,:@:]^:[&.> ,&:<)
You will be unhappily suprised:
0 1 2 dbp i. 2 2 3
0 0 0
0 1 2 okp~ i. 2 2 3
0 0 0
0 0 1
0 0 2
4 5 dbp i. 2 2 3
0 1 1
4 5 okp~ i. 2 2 3
0 1 1
0 1 2
Otherwise if you intended to replace idx0 =. $ #: I.@:, then note that (A)
you cannot claim the advantage of "decreased complexity", (B) idx0@:= will
return ALL the indices where x = y whereas okp will only return the FIRST
index, and (C) the verb idx0@:f will return the indices where the predicate
f holds, for any predicate at all. Therefore okp is less general.
-Dan
PS: Plus ,:^:(difference in rank) is cool! The sentence x -: #@:$ ,:^:(x
-~ #@:$y) y is a tautology, no matter whether x -~ #@:$ y is positive,
negative, or zero!
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