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Re: Rosetta Code: Top rank per group

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On Mon, 8 Dec 2014 16:43:22 -0800 (PST)
hughaguilar96@gmail.com wrote:

> On Wednesday, February 12, 2014 6:37:15 PM UTC-7, Julian Fondren
> wrote:
> > 1. brute-force the answer with high-level data structures: walk the
> > table, adding departments as keys to a hash table, the values of
> > which are lists of salaries.  Once you've exhausted the table, sort
> > the keys of the hash (for nice output) and then print them and
> > their top N of the sorted lists of salaries.
> > 
> > (If you've never used a Perl oneliner that you wrote in a minute to
> > chew on multiple repquota streams and spit out the top
> > diskspace-using users, then that I call this a 'good solution' may
> > puzzle you.)
> 
> A program like this is trivial using my ASSOCIATION.4TH in the novice
> package: http://www.forth.org/novice.html
> It uses an LLRB tree internally, and it allows associations (or
> subsets of associations) to be traversed in order. I would just build
> one association sorted by department, then for each department I
> would build an association sorted by salary, then just dump out the
> leftmost N nodes. For a real program that has a lot of data and has
> to be robust, it would make more sense to build an association sorted
> by name, and then build associations sorted by department, salary,
> etc. in which the record is a pointer to a node in the main
> association --- like a relational-database, this saves memory by not
> replicating data.

Hm, sounds complicated. SQL/Database is best for such tasks...
You just have to send SQL command and that's all. Not worth a fuss...

> 
> I don't think Rosetta Stone allows the use of libraries however ---
> so it favors languages such as Perl that have data-structures built
> in --- if the programmer has to implement all of these
> data-structures from scratch as Elizabeth Rather demands her cult
> members to do, the program is going to be huge and complicated. It
> will also likely use an inefficient data-structure such as a basic
> binary-tree rather than an LLRB tree, because implementing an LLRB
> tree for a single program is way too much work.

What's so good about LLRB tree? I think that classical RB tree
performs better. Only advantage of LLRB is like AA tree ease
of implementation, I guess...

> 
> Actually, implementing a basic binary tree with insert and delete is
> a lot of work too,

Nope, not much of a code. It requires some thinking but nothing 
one cannot finish in couple of days.

 if it has to be done from scratch for every
> program.

One can write it once and use it in every other program.
It is not necessary to write everytime one starts new
program. Problem is that like C (which also doesn;t have
standard container library) Forth is low level language
and people can't agree on interface. 

 This is why ANS-Forth is never used in commercial
> programming --- implementing everything from scratch is just too much
> work --- the boss expects a trivial program like this to be done in
> an hour or two, and he will fire a programmer who spends a week on it
> and then says: "Well, um, I'm bogged down in figuring out how LLRB
> trees work, as they are quite complicated!"

There is internet, but then again, there are programmers that make
memory leaks in Java :p

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Re: Rosetta Code: Top rank per group hughaguilar96@gmail.com - 2014-12-08 16:43 -0800
  Re: Rosetta Code: Top rank per group Melzzzzz <mel@zzzzz.com> - 2014-12-09 05:08 +0100
    Re: Rosetta Code: Top rank per group hughaguilar96@gmail.com - 2014-12-09 21:43 -0800
      Re: Rosetta Code: Top rank per group hughaguilar96@gmail.com - 2014-12-09 21:55 -0800
        Re: Rosetta Code: Top rank per group november.nihal@gmail.com - 2014-12-10 03:40 -0800
          Re: Rosetta Code: Top rank per group hughaguilar96@gmail.com - 2014-12-11 19:15 -0800
            Re: Rosetta Code: Top rank per group hughaguilar96@gmail.com - 2014-12-13 09:11 -0800
              Re: Rosetta Code: Top rank per group "WJ" <w_a_x_man@yahoo.com> - 2014-12-15 06:08 +0000
              Re: Rosetta Code: Top rank per group "WJ" <w_a_x_man@yahoo.com> - 2014-12-17 02:50 +0000
                Re: Rosetta Code: Top rank per group hughaguilar96@gmail.com - 2014-12-18 22:06 -0800
                Re: Rosetta Code: Top rank per group hughaguilar96@gmail.com - 2014-12-21 17:14 -0800
                Re: Rosetta Code: Top rank per group Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2014-12-22 10:27 +0000
                Re: Rosetta Code: Top rank per group hughaguilar96@gmail.com - 2014-12-22 22:03 -0800
                Re: Rosetta Code: Top rank per group hughaguilar96@gmail.com - 2015-01-08 17:17 -0800
                Re: Rosetta Code: Top rank per group Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2015-01-09 09:56 +0000
                Re: Rosetta Code: Top rank per group hughaguilar96@gmail.com - 2015-03-16 19:11 -0700
                Re: Rosetta Code: Top rank per group "WJ" <w_a_x_man@yahoo.com> - 2014-12-24 05:25 +0000
  Re: Rosetta Code: Top rank per group mix <mix@test.net> - 2014-12-14 11:55 +0000
    Re: Rosetta Code: Top rank per group empty-buffers <empty.buffersYOU-DONT-WANT-THIS@gmail.NEITHER-THIS.com> - 2014-12-14 13:52 +0000
  Re: Rosetta Code: Top rank per group mix <mix@test.net> - 2014-12-14 11:58 +0000

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