ind4=: [: 4&$.$.

   ts 'ind2 tmp'
0.256588267503 134218688
   ts 'ind4 tmp'
0.114605347886 2048

Wow!

> -----Original Message-----
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED] On Behalf Of Don Guinn
> Sent: Thursday, 12 June 2008 23:42
> To: Programming forum
> Subject: Re: [Jprogramming] find row and column indices
>
> How about?
>    4$.$.tst
> 0 3
> 2 0
> 3 3
> 5 0
>
> On Wed, Jun 11, 2008 at 6:34 PM, Sherlock, Ric
> <[EMAIL PROTECTED]>
> wrote:
>
> > Thanks Roger & Henry,
> > They are much simpler than the other way I just realised I
> had already
> > created in the other thread.
> >
> > ind0=: (1 , {:@$) *"1 [: (<. ,. 1&|) {:@$ %~ [: I. ,  NB. RS
> > ind1=: [:;(i.@:# ,.&.> <@I.)  NB. RS
> > ind2=: $ #: I.@,   NB. RH & HR
> > ind3=: , # (#: i.@(*/))@$  NB. HR
> >
> > Interestingly ind0 is actually very competitive with ind2,
> but would need
> > more work to sort out tolerance (and is specific to matrices).
> >   tmp=: 0.0000001>1e6 [EMAIL PROTECTED]
> >   +/+/tmp
> > 9
> >   ts=: 6!:2 , 7!:[EMAIL PROTECTED]
> >
> >   ts 'ind0 tmp'
> > 0.264977043172 134218688
> >   ts 'ind1 tmp'
> > 3.26141171573 221066560
> >   ts 'ind2 tmp'
> > 0.2667722434 134218688
> >   ts 'ind3 tmp'
> > |out of memory: ind3
> > |       ind3 tmp
> >
> > ---Roger Hui wrote:
> > > ($tst) #: I. , tst
> > >
> > > Works for any rank array, not just matrices.
> >
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> >
> >
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