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From: jaxon@sp27.csrd.uiuc.edu (Greg P. Jaxon)
Newsgroups: comp.lang.apl
Subject: Re: WANTED: a way to sort array so each column i
Message-ID: <1991Apr26.190032.11576@csrd.uiuc.edu>
Date: 26 Apr 91 19:00:32 GMT
References: <1991Apr17.151913.4891@csrd.uiuc.edu> <WEG.91Apr17130250@convx1.convx1.ccit.arizona.edu> <1991Apr19.145007.2201@csrd.uiuc.edu> <567@kepler1.kepler.com>
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rjfrey@kepler.com (Robert J Frey) writes:
>Without a rank operator or a very general axis "operator" I don't see how most
>APL's could avoid breaking the array into separate columns
   It's horridly inefficient, but you could:
 $   Z is COLUMN_SORT A;#IO;#CT;T
[1]  #IO is #CT is 0
[2]  T is reverse rho A
[3]  Z is grdn  A is ,A
[4]  Z is A[transpose T rho Z[grup T[0]|Z]]
 $

in any ISO standard APL.

>SORTED_ARRAY assign mix[0.1] sort foreach split[1] ARRAY
   This keeps coming up  ^^^ does some APL actually define mix
   using fractional axis numbers?  mix[#IO] sort" split[#IO].

   This is a good pattern to know just generally, because it 
   covers most uses of the J (APL Dictionary) rank operator.