ind4a=: 4 $. $.


----- Original Message -----
From: "Sherlock, Ric" <[EMAIL PROTECTED]>
Date: Thursday, June 12, 2008 6:07
Subject: RE: [Jprogramming] find row and column indices
To: Programming forum <[email protected]>

>   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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