[Jprogramming] Recurring holiday amusement

[Raul Miller]

recur=: ^:
fib=: , +/@{.~&_2
arith=: ] , +&{:
e=: ] , [ (^t.@] * ^) #@]

-- 
Raul

On Sun, Dec 23, 2012 at 10:00 PM, km <km at math.uh.edu> wrote:
> Write a conjunction recur and verbs fib, arith, and e that do the following
>
>     fib recur 5 [ 1 1  NB. five additional terms of Fibonacci sequence
>  1 1 2 3 5 8 13
>     0.5&arith recur 5 [ 3
>  3 3.5 4 4.5 5 5.5
>     1&e recur 5 [ ''
>  1 1 0.5 0.166667 0.0416667
>     +/ 1&e recur 10 [ ''
>  2.71828
>     +/ _1&e recur 10 [ ''
>  0.367879
>     ^ 1 _1
>  2.71828 0.367879
>
> Conjunction recur helps create "recursive" lists.
>
> Kip Murray
>
> Sent from my iPad
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