[Jprogramming] Choosing k items out of n

[R.E. Boss]

A minor improvement:

 

chs=: 4 : ';(,/@:(([,. ]+ <:)"0 _) )&.>/ |. 0((,.&.>@{)`[`])} <@i."0
(>:y-x)+i.x'

 

to force a 2-cell for x=1 :

 

   1 chs 3

0

1

2

   2 chs 3

0 1

0 2

1 0

1 2

2 0

2 1

 

 

R.E. Boss

 

 

> -----Oorspronkelijk bericht-----

> Van: programming-bounces at jsoftware.com [mailto:programming-

> bounces at jsoftware.com] Namens Raul Miller

> Verzonden: zaterdag 2 augustus 2008 17:06

> Aan: Programming forum

> Onderwerp: Re: [Jprogramming] Choosing k items out of n

> 

> On Sat, Aug 2, 2008 at 1:49 AM, R.E. Boss <r.e.boss at planet.nl> wrote:

> > chs=: 4 : ';(,/@:(([,. ]+ <:)"0 _) )&.>/ |.<@i."0 (>:y-x)+i.x'

> 

> That's beautiful.

> 

> I hope you do not mind if I re-express this slightly:

>    cs=: ;@(,/@:(([ ,. <:+])"0 _)&.>/)@(i.&.>@{. 1+i. at -)

> 

> --

> Raul

> ----------------------------------------------------------------------

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