[Jprogramming] minmax differences

[R.E. Boss]

   5 mmd 10
+---------+---------+
|0 2 4 6 8|0 2 4 6 9|
|1 3 5 7 9|0 2 4 7 9|
|         |0 2 5 7 9|
|         |0 3 5 7 9|
+---------+---------+

   k 5 comb 10	NB. match
0 2 4 6 9
0 2 4 7 9
0 2 5 7 9
0 3 5 7 9

   5 mmd 12
+----------+----------+----------+----------+
|0 2 4 6  8|0 2 4 6  9|0 2 4 6 10|0 2 4 6 11|
|1 3 5 7  9|0 2 4 7  9|0 2 4 8 10|0 2 4 9 11|
|2 4 6 8 10|0 2 5 7  9|0 2 6 8 10|0 2 7 9 11|
|3 5 7 9 11|0 3 5 7  9|0 4 6 8 10|0 5 7 9 11|
|          |0 2 4 7 10|0 2 4 7 11|          |
|          |0 2 5 7 10|0 2 5 7 11|          |
|          |0 3 5 7 10|0 3 5 7 11|          |
|          |1 3 5 7 10|1 3 5 7 11|          |
|          |0 2 5 8 10|0 2 4 8 11|          |
|          |0 3 5 8 10|0 2 6 8 11|          |
|          |1 3 5 8 10|0 4 6 8 11|          |
|          |0 3 6 8 10|0 2 5 9 11|          |
|          |1 3 6 8 10|0 3 5 9 11|          |
|          |1 4 6 8 10|1 3 5 9 11|          |
|          |0 2 5 8 11|0 2 6 9 11|          |
|          |0 3 5 8 11|0 4 6 9 11|          |
|          |1 3 5 8 11|0 3 7 9 11|          |
|          |0 3 6 8 11|1 3 7 9 11|          |
|          |1 3 6 8 11|0 4 7 9 11|          |
|          |1 4 6 8 11|1 5 7 9 11|          |
|          |2 4 6 8 11|          |          |
|          |0 3 6 9 11|          |          |
|          |1 3 6 9 11|          |          |
|          |1 4 6 9 11|          |          |
|          |2 4 6 9 11|          |          |
|          |1 4 7 9 11|          |          |
|          |2 4 7 9 11|          |          |
|          |2 5 7 9 11|          |          |
+----------+----------+----------+----------+

   k 5 comb 12	NB. no match; second box
0 2 5 8 11
0 3 5 8 11
0 3 6 8 11
0 3 6 9 11


For mmd, see
http://jsoftware.com/pipermail/programming/2009-August/015925.html


R.E. Boss


> -----Oorspronkelijk bericht-----
> Van: programming-bounces at jsoftware.com [mailto:programming-
> bounces at jsoftware.com] Namens John Randall
> Verzonden: maandag 17 augustus 2009 21:23
> Aan: Programming forum
> Onderwerp: Re: [Jprogramming] minmax differences
> 
> Raul Miller wrote:
> > require 'stats'
> >
> > Given a result from comb pick the entries which
> > maximize the minimum difference between
> > any two adjacent entries.
> >
> 
> Raul, could you give some more examples of expected results?
> 
> My solution
> 
> sdiff=:(/:~"1 )@:( 2 -~/\"1 ])
> k=:((] -:"1 {.@:\:~)@: sdiff) # ]
> 
> gives the correct result
> 
>    k 3 comb 8
> 0 3 7
> 0 4 7
> 
> on the example data.
> 
> My approach is to sort the differences for each combination, pick the
> lexicographically greatest, and use this to select combinations.  Will
> this do the trick, or am I misunderstanding the problem?
> 
> Best wishes,
> 
> John
> 
> 
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