Special code for
10 ts 'xx=: xx ii}~ ii reverse xx'
0.0136772 4.19616e6
might be worth doing ( name=: name foo}~ bar )
----- Original Message -----
From: R&S HUI <[EMAIL PROTECTED]>
Date: Wednesday, July 12, 2006 2:27 pm
Subject: Re: [Jprogramming] special coding for stack operations
> It makes a significant difference if you "put the data back",
> i.e. do the operation in place:
>
> 10 ts 'ii reverse`[`]}xx'
> 0.0131137 4.1968e6
> 10 ts '(ii reverse xx) ii}xx'
> 0.0127947 4.19597e6
> 10 ts 'xx=: (ii reverse xx) ii}xx'
> 1.00851e_5 1792
>
> The last benchmark would be the goal for the prospective special
> code for the following:
>
> 10 ts 'xx=: ii reverse`[`]}xx'
> 0.0136649 4.19686e6
>
> But perhaps the special code is not needed? There isn't
> much difference between the two:
>
> xx=: (ii reverse xx) ii}xx
> xx=: ii reverse`[`]}xx
>
> Not enough to justify a lot of work and more specialness.
>
>
>
> ----- Original Message -----
> From: greg heil <[EMAIL PROTECTED]>
> Date: Wednesday, July 12, 2006 2:09 pm
> Subject: Re: [Jprogramming] special coding for stack operations
>
> > On 7/12/06, R&S HUI <[EMAIL PROTECTED]> wrote:
> > > The prospects for more efficient computation improves if you say
> > name=: x u@:{`[`]} name NB. (0)
> > name=: x u`[`]} name NB. (1)
> > instead of
> > name=: x reverse amend name NB. (2)
> > name=: x |.@:{ amend name NB. (3)
> > It is easier and more productive for the prospective special
> code to
> > handle (0) and (1) than (2) or (3).
> >
> > i do gather that special code does not like "cover functions". But
> > currently the flexibility/generality offered by the namings does not
> > seem to make a significant difference:
> >
> > ii=:(1 2; 2 0)
> > xx=:i. 999 999
> > 10 Ts 'ii reverse`[`]} xx'
> > 0.0163818 4.1968e6
> > 10 Ts 'ii ([:|.{)`[`]} xx'
> > 0.0192198 4.19686e6
> > 10 Ts 'ii reverse amend xx'
> > 0.0194623 4.19674e6
> > 10 Ts 'ii swapG xx'
> > 0.0159129 4.19578e6
> >
> > i had been hoping there might be a more efficient way of doing
> > what i
> > was doing...
> >
> > Is there some prospect for special coding for this more generic swap
> > functionality? i would certainly forgo the perspicuity and
> generality> if there were such a prospect - though i dislike such
> hard coding
> > which is hard to maintain and read. It is a significant time
> sink in
> > my app.
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