More faithful to the specs (actually doing interchanges).
Also using components.

   ix=: C.~ <@~.@(0, (i. <./)) 
   ss1=: ({. , $:@}.)@ix^:(*...@#)

   data
6 15 19 12 14 19 0 17 0 14
   ix data
0 15 19 12 14 19 6 17 0 14
   ss1 data
0 0 6 12 14 14 15 17 19 19



----- Original Message -----
From: Roger Hui <[email protected]>
Date: Monday, August 31, 2009 13:03
Subject: Re: [Jprogramming] Selection Sort
To: Programming forum <[email protected]>

> A problem not worth solving is not worth solving well?
> For whatever it's worth:
> 
>    ss=: (i.<./) ({ , $:@((~:i...@#) # ]))^:(*...@#@]) ]
> 
>    ] data=: 10 ?...@$ 20
> 6 15 19 12 14 19 0 17 0 14
>    ss data
> 0 0 6 12 14 14 15 17 19 19
> 
> 
> 
> ----- Original Message -----
> From: Alex Rufon <[email protected]>
> Date: Monday, August 31, 2009 12:49
> Subject: [Jprogramming] Selection Sort
> To: Programming forum <[email protected]>
> 
> > I can't sleep so I tried working on Selection Sort which states:
> > 
> > First find the smallest element in the array and exchange it 
> > with the element in the first position, then find the second 
> > smallest element and exchange it with the element in the 
> second 
> > position, and continue in this way until the entire array is 
> > sorted. Its asymptotic complexity is 
> > O<http://rosettacode.org/wiki/O>(n2) making it inefficient 
> on 
> > large arrays.
> > http://rosettacode.org/wiki/Selection_sort
> > 
> > The best I can do is:
> > selectionSort=: verb define
> > data=. y
> > for_xyz. y do.
> >   temp=. xyz_index }. data
> >   nvidx=. xyz_index + temp i. <./ temp
> >   data=. ((xyz_index, nvidx) { data) (nvidx, xyz_index) } data
> > end.
> > data
> > )
> > 
> > 
> > NB. We generate 10 random numbers between 0 and 99 and assign 
> to 
> > a variable
> > 
> >    [data=. 10 ? 100
> > 
> > 51 18 81 46 11 54 74 63 56 76
> > 
> >    selectionSort data
> > 
> > 11 18 46 51 54 56 63 74 76 81
> > 
> > I tried figuring out how to do this without looping but I 
> can't. 
> > Can it be done without loops?
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