replaceZeroes 0 0
_1 _1 1 _1 _1 _1 1 1 _1 1 1 _1 _1 1 1 1
>;<@,@:{"1 (<1 _1)(0([EMAIL PROTECTED] <@#: I.@,@:=) M)}<"0 M=:0 0
1 1
1 _1
_1 1
_1 _1
Apparently replaceZeroes generates too much.
R.E. Boss
> -----Oorspronkelijk bericht-----
> Van: [EMAIL PROTECTED] [mailto:programming-
> [EMAIL PROTECTED] Namens R.E. Boss
> Verzonden: zondag 9 maart 2008 23:11
> Aan: 'Programming forum'
> Onderwerp: RE: [Jprogramming] Turning 0 into _1 1 in a list
>
> Oops, last one should be
>
> >;<@,@:{"1 (<1 _1)(0([EMAIL PROTECTED] <@#: I.@,@:=) M)}<"0 M
> 1 _1 1 1
> 1 _1 _1 1
> 1 1 _1 1
> 1 1 1 _1
> 1 1 _1 _1
> _1 1 1 _1
> _1 1 _1 _1
>
>
> R.E. Boss
>
>
> > -----Oorspronkelijk bericht-----
> > Van: [EMAIL PROTECTED] [mailto:programming-
> > [EMAIL PROTECTED] Namens R.E. Boss
> > Verzonden: zondag 9 maart 2008 22:57
> > Aan: 'Programming forum'
> > Onderwerp: RE: [Jprogramming] Turning 0 into _1 1 in a list
> >
> > [M=:1 _1 0 1,1 1 _1 1,:0 1 0 _1
> > 1 _1 0 1
> > 1 1 _1 1
> > 0 1 0 _1
> >
> > 0([EMAIL PROTECTED] <@#: I.@,@:=) M
> > +---+---+---+
> > |0 2|2 0|2 2|
> > +---+---+---+
> > NB. coordinates of zeroes
> >
> > (<1 _1)(0([EMAIL PROTECTED] <@#: I.@,@:=) M)}<"0 M
> > +----+--+----+--+
> > |1 |_1|1 _1|1 |
> > +----+--+----+--+
> > |1 |1 |_1 |1 |
> > +----+--+----+--+
> > |1 _1|1 |1 _1|_1|
> > +----+--+----+--+
> > NB. replace boxed zeroes by 1 _1
> >
> > <@{"1 (<1 _1)(0([EMAIL PROTECTED] <@#: I.@,@:=) M)}<"0 M
> > +--------------------+----------+----------------------+
> > |+--------+---------+|+--------+|+---------+----------+|
> > ||1 _1 1 1|1 _1 _1 1|||1 1 _1 1|||1 1 1 _1 |1 1 _1 _1 ||
> > |+--------+---------+|+--------+|+---------+----------+|
> > | | ||_1 1 1 _1|_1 1 _1 _1||
> > | | |+---------+----------+|
> > +--------------------+----------+----------------------+
> > NB. use catalogue to make all combinations
> >
> > >,;<@{"1 (<1 _1)(0([EMAIL PROTECTED] <@#: I.@,@:=) M)}<"0 M
> > 1 _1 1 1
> > 1 _1 _1 1
> > 1 1 _1 1
> > 1 1 _1 1
> > 1 1 1 _1
> > 1 1 _1 _1
> > _1 1 1 _1
> > _1 1 _1 _1
> >
> >
> > replaceZeroes M
> > 1 _1 _1 1 1 _1 1 1 1 1 _1 1 _1 1 _1 _1 _1 1 1 _1 1 1 _1 _1 1 1 1 _1
> >
> >
> > R.E. Boss
> >
> >
> > > -----Oorspronkelijk bericht-----
> > > Van: [EMAIL PROTECTED] [mailto:programming-
> > > [EMAIL PROTECTED] Namens Geoff Canyon
> > > Verzonden: zondag 9 maart 2008 21:59
> > > Aan: Programming forum
> > > Onderwerp: Re: [Jprogramming] Turning 0 into _1 1 in a list
> > >
> > > I think the eventual solution I came up with was somewhat similar to
> > > this. Here's my solution:
> > >
> > > replaceZeroes =: (;@:;@:(_4([:<(((_1 1 (] i.&0)}"0 1 ])`])@.(# =
> > > i.&0)))\]))^:_
> > >
> > > I spent some time trying to figure out how to apply the replacement
> > > repeatedly before boxing and then unbox at the end, to minimize
> boxing/
> > > unboxing, but I couldn't get that to work. So in the above, the
> boxing/
> > > unboxing happens for each replacement. This isn't so bad in my
> > > particular case since no list has more than three zeroes in it. If the
> > > lists had many zeroes, the whole thing would come apart, since I'm
> > > starting with 512 lists of 27 elements, so a bunch of zeroes would
> > > quickly result in millions of lists. As it is, I end up with less than
> > > a thousand.
> > >
> > > Still I wonder that there seems to be no way to avoid boxing/unboxing?
> > > If I have a list and I want to transform that list, with the subsets I
> > > take potentially changing in length, I can't do that without boxes?
> > >
> > > Say I have a list like this: 1 2 3 4 5 6 7 8
> > >
> > > And I want the result to be a list that a duplicate for each prime in
> > > the list:
> > >
> > > 1 2 2 3 3 4 5 5 6 7 7 8
> > >
> > > Are boxes the only/best way?
> > >
> > > regards,
> > >
> > > Geoff
> > >
> > > On Mar 4, 2008, at 5:17 AM, Raul Miller wrote:
> > >
> > > > I have some comments in addition to R.E.Boss's comments
> > > > (and using his M)
> > > > M=:1 _1 0 1,1 1 _1 1,:0 1 0 _1
> > > >
> > > > A simple approach to supressing fill uses box (<) followed
> > > > by raze (;). In other words:
> > > >
> > > > <@(_1 1 (] i.&0)}"0 1 ])`<@.(# = i.&0)"1 M
> > > ----------------------------------------------------------------------
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> >
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>
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