Ah! The partial lists for C. confused me. mtf_under does not
reorganize the rest of the list.
9!:7'+++++++++|-'
mtf_under=: C.&.|.
mtf_aai=: (C.~ 1&, ; 0&,)~
]a=: 2 (mtf_under ,: mtf_aai) i.7
4 0 1 2 3 5 6
2 0 1 3 4 5 6
C. a
+---------+-+-+-+-+
|4 3 2 1 0|5|6| | |
+---------+-+-+-+-+
|2 1 0 |3|4|5|6|
+---------+-+-+-+-+
Thank you again. The experiments I tried before asking were...flawed.
> Date: Tue, 31 Jan 2012 10:44:53 -0500
> From: David Ward Lambert <b49p23t...@stny.rr.com>
> Subject: [Jprogramming] Understanding C. , A.
> Message-ID: <1328024693.27264.19.camel@lambertdw>
> Are there simple versions of swap and of move_to_front that use C. ,
> A.
> or (other)? My definitions use amend. Thank you, Dave.
>
> 1 5 swap 'abcdefgh'
> afcdebgh
>
> 3 move_to_front 'abc*ef'
> *abcef
>
>
> swap=: ({~ |.)~`[`]}
> move_to_front=: ((({~ _1&|.)~`[`]})~ i.@:>:)~
>
>
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