DATA=: ".;._2]0 :0 0 0 1 1 1 1 2 2 2 2 2 4 4 4 5 5 5 0 7 8 9 2 2 5 5
5 3 8 0 0 5 6)
(</./ #inv~ (e.~ i.@(1 + >./))@{. ) DATA
+---+-------+---------++-----+---+
|5 0|7 8 9 2|2 5 5 5 3||8 0 0|5 6|
+---+-------+---------++-----+---+
However, this is quirky -- it assumes that you do not want any empty
boxes on the right hand side of the result. If you want those empty
boxes you will need a way of specifying their presence:
6 (</./@] #inv~ i.@[ e. {.@] ) DATA
+---+-------+---------++-----+---+
|5 0|7 8 9 2|2 5 5 5 3||8 0 0|5 6|
+---+-------+---------++-----+---+
Here, the left argument tells us the length of the argument.
Then again, you could achieve the same thing with my first expression:
6 {. (</./ #inv~ (e.~ i.@(1 + >./))@{. ) DATA
+---+-------+---------++-----+---+
|5 0|7 8 9 2|2 5 5 5 3||8 0 0|5 6|
+---+-------+---------++-----+---+
I could not choose between these options without better understanding
your application.
FYI,
--
Raul
On Tue, Jan 10, 2012 at 9:40 AM, Ben Gorte - LR <b.g.h.go...@tudelft.nl> wrote:
> Dear Forum,
>
> Perhaps it is a beginners question, but somehow I cannot come up with a
> decent answer.
>
> I have a matrix like of position-value pairs like:
>
> 0 0 1 1 1 1 2 2 2 2 2 4 4 4 5 5
> 5 0 7 8 9 2 2 5 5 5 3 8 0 0 5 6
>
> (it could also be transposed), and I would like to have a list of boxes:
>
> +---+-------+---------++-----+---+
> |5 0|7 8 9 2|2 5 5 5 3||8 0 0|5 6|
> +---+-------+---------++-----+---+
>
> So the values are placed in boxes according to the positions.
>
> My matrix above is sorted (from left to right), but probably this is not
> essential for most solutions. Furthermore, the order of the elements within
> the boxes of the result is not important for the remainder of my algorithm.
>
> I have a solution that loops through the matrix from left to right, but it is
> way too slow (and it does not look like J). Isn't there a better way?
>
> Thanks,
> Ben
>
>
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