Wait just a second...
dd=.1e5?2e9
6!:2 '(10&#.^:_1 )&.>dd'
3.31308
6!:2 '(''0123456789'' i. ":)&.>dd'
0.119448
6!:2 ' "."0@":&.>dd'
0.0710835
6!:2 '(10&#.^:_1) dd'
0.0532393
6!:2 ' "."0@":"0 dd'
0.0829183
The fastest non-padded execution is actually ("."0@":), just as promised.
(10&#.^:_1) is only faster for arrays because it doesn't have to be run with
rank 0.
Somebody resolve this quick--I accidentally typed ". instead of {. while
looking at this!
Marshall
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Roger Hui
Sent: Wednesday, September 01, 2010 8:28 PM
To: Programming forum
Subject: Re: [Jprogramming] Splitting an integer into its digits
The second expression can be simplified to
('0123456789' i. ":)&.>dd
which would make much it easier to understand and 50% faster.
10&#. b. _1
($&10@>:@(10&(<....@^.))@(1&>.)@(>./)@:|@, #: ]) :.(10&#.)
reveals why 10&#.^:_1 is so much slower and points to substantial room for
improvement if we decide to do something about it.
----- Original Message -----
From: Devon McCormick <[email protected]>
Date: Wednesday, September 1, 2010 17:03
Subject: Re: [Jprogramming] Splitting an integer into its digits
To: Programming forum <[email protected]>
> dd=. 1e5?2e9
> 6!:2 '(10&#.^:_1 )&.>dd'
> 3.7797712
> 6!:2 '((<''0123456789'')i.&>":&.>)&.>dd'
> 0.15169945
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