Another alternative.  Actually an alternative for i.~ for this data
whose speed relative to i.~ depends on the kind of data.

f2=: [EMAIL PROTECTED] - i.~
f3=: [EMAIL PROTECTED] - (# +/[EMAIL PROTECTED]:@(0&,))@(#;.1)@(1,2~:/\])

   c=: 1e5 [EMAIL PROTECTED] 10
   x=: c#i.#c
   y=: 0.5 * x

   (f2 -: f3) x
1
   (f2 -: f3) y
1

   ts=: 6!:2 , 7!:[EMAIL PROTECTED]

   ts 'f2 x'
0.0192337 6.29222e6
   ts 'f3 x'
0.0444705 7.86509e6

   ts 'f2 y'
0.150214 6.29222e6
   ts 'f3 y'
0.0593807 7.86509e6

#;.1@(1,2~:/\]) is an alternative to #/.~ which may be
faster or slower depending on the kind of data.
(Slower on "easy" data; faster on "hard" data.)

   (#/.~ -: #;.1@(1,2~:/\])) x
1
   (#/.~ -: #;.1@(1,2~:/\])) y
1
   ts '#/.~ x'
0.00797168 1.04941e6
   ts '#;.1@(1,2~:/\]) x'
0.0135623 1.05043e6
   ts '#/.~ y'
0.144353 6.29229e6
   ts '#;.1@(1,2~:/\]) y'
0.0258773 1.05043e6



----- Original Message -----
From: Henry Rich <[EMAIL PROTECTED]>
Date: Tuesday, July 31, 2007 6:24
Subject: RE: [Jprogramming] simple verb
To: 'Programming forum' <[email protected]>

> Another solution is
> 
>    ([EMAIL PROTECTED] - i.~) 4 4 4 2 2 1 3 3 3 3
> 0 1 2 0 1 0 0 1 2 3 
> 
> JfC shows Roger's solution for scrambled inputs.
> 
> Henry Rich
> 
> > -----Original Message-----
> > From: [EMAIL PROTECTED] 
> > [mailto:[EMAIL PROTECTED] On Behalf Of R.E. Boss
> > Sent: Tuesday, July 31, 2007 8:59 AM
> > To: 'Programming forum'
> > Subject: RE: [Jprogramming] simple verb
> > 
> > Alternative:
> > 
> >    (0:`+ @.[)/\.&.|. 0,2=/\4 4 4 2 2 1 3 3 3 3
> > 0 1 2 0 1 0 0 1 2 3
> > 
> > Works alsof or scrambled:
> > 
> >    (0:`+ @.[)/\.&.|. 0,2=/\3 1 4 3 3 4 3 2 4 2
> > 0 0 0 0 1 0 0 0 0 0
> > 
> > 
> > R.E. Boss
> > 
> > 
> > 
> > > -----Oorspronkelijk bericht-----
> > > Van: [EMAIL PROTECTED] [mailto:programming-
> > > [EMAIL PROTECTED] Namens Mike Day
> > > Verzonden: dinsdag 31 juli 2007 12:27
> > > Aan: Programming forum
> > > CC: [EMAIL PROTECTED]
> > > Onderwerp: Re: [Jprogramming] simple verb
> > > 
> > > Damien
> > > 
> > > This works, but only if the data is in the form
> > >    [x =: 3 2 1 4 # 4 2 1 3
> > > 4 4 4 2 2 1 3 3 3 3
> > >    NB. and not scrambled, eg
> > >    y =: 3 1 4 3 3 4 3 2 4 2
> > > 
> > >    ;@((<@[EMAIL PROTECTED])/.~)x  NB. developed 
> from your solution
> > > 0 1 2 0 1 0 0 1 2 3
> > > 
> > > Is that what you need or do you also need a
> > > result for scrambled x?
> > > 
> > > Mike
> > > 
> > > Damien wrote:
> > > > Hi,
> > > >
> > > > I have a problem to create a verb. I think it is quite 
> easy, but
> > > > unfortunately I can not.
> > > >
> > > > My Input (example) :     4 4 4 2 2 1 3 
> 3 3 3
> > > > As output, I would :       0 
> 1 2 0 1 0 0 1 2 3
> > > >
> > > > I would like a verb which counts the iteration number for 
> > same element.
> > > > It is equivalent to : (i. 3) , ( i. 2) , ( i. 1) , ( i. 4)
> > > > I can do the line above because of the parenthesis.
> > > > I can only get the vector : 3 2 1 4 easily with #/.~, but 
> > that is all.

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