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Subject: RE: WANTED:  a way to sort array so each column i
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Date: 14 Apr 91 18:40:04 GMT
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Eythan Weg  >
A Analla    >***

>*** Could some please suggest a generic function to reorder each column
>*** of an array in descending order where the array is two dimensional.
>  [paraphrased slightly] in J, use      \:"1&.|:~ array    

>Incidentally, how does one write this function in APL2?

In APL2, you could write a function to do sorting:

_
V R <- F Y
_ R <- Y[gradedown Y]
V

then do:
         transpose mix  F each  split[quadIO] array

You might be able to do something with mix and brackets to avoid the
transpose, but I don't know what exactly, off the top of my head.

Raul Rockwell