Re: [wish] sort : what about randomization ?

[Jim Meyering]

Paul Eggert <address@hidden> wrote:
> It'd be an amusing option to build, albeit not as easy as one might
> think at first glance.  Here's a proposed addition to the coreutils
> TODO list.

This functionality has been requested often enough that I suspect the
alternatives (scripts galore and programs like bogosort) aren't widely
available.  I've added it.

> Or perhaps we should have a different program (unsort? assort?) instead.

If it's not too invasive, I like the idea of adding it to sort,
since, as Stepan suggested, it could then be used to operate on
individual fields along with other sorting options.

> --- ../coreutils/TODO Mon Jul 14 11:39:37 2003
> +++ TODO      Thu Jul 17 15:42:57 2003
> @@ -86,3 +86,13 @@ sort: Compress temporary files when doin
>    This improves performance when you can compress/uncompress faster than
>    you can read/write, which is common in these days of fast CPUs.
>    suggestion from Charles Randall on 2001-08-10
> +
> +sort: Add an ordering option -R that causes 'sort' to sort according
> +  to a random permutation of the correct sort order.  Also, add an
> +  option --random-seed=SEED that causes 'sort' to use an arbitrary
> +  string SEED to select which permutations to use, in a deterministic
> +  manner: that is, if you sort a permutation of the same input file
> +  with the same --random-seed=SEED option twice, you'll get the same
> +  output.  The default SEED is chosen at random, and contains enough
> +  information to ensure that the output permutation is random.
> +  suggestion from Feth AREZKI, Stephan Kasal, and Paul Eggert on 2003-07-17