2006/11/16, Mike Day <[EMAIL PROTECTED]>:
So does this satisfy your requirements?
1 ((>./\@([ {. <[EMAIL PROTECTED] # [EMAIL PROTECTED])~ #) </. ]) i.10
+-------------------+
|0 1 2 3 4 5 6 7 8 9|
+-------------------+
2 ((>./\@([ {. <[EMAIL PROTECTED] # [EMAIL PROTECTED])~ #) </. ]) i.10
+---------+---------+
|0 1 2 3 4|5 6 7 8 9|
+---------+---------+
3 ((>./\@([ {. <[EMAIL PROTECTED] # [EMAIL PROTECTED])~ #) </. ]) i.10
+-----+-----+-------+
|0 1 2|3 4 5|6 7 8 9|
+-----+-----+-------+
7 ((>./\@([ {. <[EMAIL PROTECTED] # [EMAIL PROTECTED])~ #) </. ]) i.10
+-+-+-+-+-+-+-------+
|0|1|2|3|4|5|6 7 8 9|
+-+-+-+-+-+-+-------+
It doesn't check the ordering of the input list. What should be
the result for 10?10 ?
Compare
3 ((((-@ <[EMAIL PROTECTED] )~)#)<\]) q=: 0 1 8 2 6 7 9 4 5 3
+-----+-----+-------+
|0 1 8|2 6 7|9 4 5 3|
+-----+-----+-------+
3 f q NB. June Kim's "f"
+-------+---------+-+
|0 1 8 2|6 7 9 4 5|3|
+-------+---------+-+
Yes, you are right and my second f was wrong. I mistakingly considered
the input as i. N. However, my first version of f in the original post
works correct.
Thanks.
Mike
June Kim wrote:
> Well, it doesn't work in the case of K=4 and N=10.
>
> (-<.10%4) ((*@|@|#) (]`(_2:(}.,[:,&.>/{.)])@.[) <\) i.10
> +---+---+---+---+---+
> |0 1|2 3|4 5|6 7|8 9|
> +---+---+---+---+---+
>
> They are five segments, instead of four(K). What actually it should
> return is:
> 4 f i.10
> +---+---+---+-------+
> |0 1|2 3|4 5|6 7 8 9|
> +---+---+---+-------+
>
>
> 2006/11/16, June Kim <[EMAIL PROTECTED]>:
>> 2006/11/15, R.E. Boss <[EMAIL PROTECTED]>:
>> > A first shot: use (-K) <\ i.N and append the content of the last
>> two boxes
>>
>> It shouldn't be (-K) <\ i.N
>>
>> K in the problem is the number of segments of the whole ordered list.
>> Therefore, it should've been <.N%K instead.
>>
>> > if the last one is a shard.
>> >
>> > _3 ((*@|@|#) (]`(_2&}.,[:,&.>/_2&{.)@.[) <\) i.10
>> > +-----+-----+-------+
>> > |0 1 2|3 4 5|6 7 8 9|
>> > +-----+-----+-------+
>> >
>> > R.E. Boss
>> >
>>
>> Thank you for your solution.
>>
>>
>> >
>> > -----Oorspronkelijk bericht-----
>> > Van: [EMAIL PROTECTED]
>> > [mailto:[EMAIL PROTECTED] Namens June Kim
>> > Verzonden: woensdag 15 november 2006 6:17
>> > Aan: Programming forum
>> > Onderwerp: [Jprogramming] Re: Coding Problem
>> >
>> > One more solution:
>> >
>> > cs=: [: <. [ %~ [: # ]
>> > b1=: 0 = cs | ]
>> > b2=: ] < [ * cs
>> > f=: (b1*.b2) < ;. 1 ]
>> >
>> >
>> > 2006/11/15, June Kim <[EMAIL PROTECTED]>:
>> > > 2006/11/15, June Kim <[EMAIL PROTECTED]>:
>> > > > from http://c2.com/cgi/wiki?CodingProblem
>> > > >
>> > > > Given K, answer an ordered collection of K ordered collections
>> of size
>> > > > approximately N / K, such that the first contains the first N / K
>> > > > objects, the second the second N / K, etc.
>> > > >
>> > > > There is a J solution on that page but it doesn't work in all
>> cases.
>> > > >
>> > > > Following is my solution (with one issue though):
>> > > > c=: [: <. [ %~ [: # ]
>> > > > hd=: ([: <: [) * c
>> > > >
>> > > > b1=: hd {.]
>> > > > b2=: hd }.]
>> > > > f=: <@b2 ,~ [EMAIL PROTECTED] <\ b1
>> > > >
>> > > > assert (0 1 2;3 4 5;6 7 8)-:3 f i.9
>> > > > assert ((,:0);1 2)-:2 f i.3
>> > > > assert (0 1 2;3 4 5;6 7 8 9)-:3 f i.10
>> > > >
>> > > > assert ((0$<''),<0 1)-: 1 f i.2 NB. $ > 1 f i.2 is 1 2,
>> not 2
>> > > > as I expected
>> > > >
>> > > > I don't like the last line -- that problem occurs once in a
>> while. How
>> > > > could I make it to pass "assert (<0 1)-:1 f i.2" with a simple
>> > > > modification?
>> > >
>> > > In other words, assert (,:<0 1)-: 1 f i.2
>> > >
>> > > Hm... Maybe I was wrong.
>> > >
>> > > My solution's result is more consistent than how I wanted the
>> result to
>> > be.
>> > >
>> > > The return value of f is, an array of rank 1. Each item of the array
>> > > is of rank 1. Then my previous solution is more consistent.
>> > >
>> > > I am sometimes confused(and make mistakes) with the fact that in
>> J we
>> > > have scalars of which rank is empty, which is different from a
>> rank-1
>> > > array of a single item. Even a boxed value can a scalar or a rank-1
>> > > array(say <1 and ,:<1).
>> > >
>> > > >
>> > > > I am interested in seeing other J solutions.
>> > > >
>> > >
>> > > Still.
>> > >
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