Re: Sorting Outline Numbers

So long as the section numbers never go above 255, this should work fine:

my @sorted =
  map join(".", map ord, split //),
  sort
  map join("", map chr, split /\./),
  @data;
[download]

It turns "4.2.1" into a three-byte string made of characters \x04, \x02, and \x01. It compares the outline numbers as strings of this form, and then expands them back to their numeral form.

Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

Comment on Re: Sorting Outline Numbers Download Code

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Re^2: Sorting Outline Numbers by hv (Prior) on Aug 11, 2005 at 01:52 UTC
Using sprintf to recreate the numbers would be rather more efficient: `my @sorted = map sprintf('%vd', $_), sort map join('', map chr, split /\./), @data;` [download] Hugo	[reply] [d/l]
Re^3: Sorting Outline Numbers by japhy (Canon) on Aug 11, 2005 at 12:25 UTC
Wow, I forgot entirely about that. I eschew the whole version-format idiom for numbers. Jeff `japhy` Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and `perl` hacker How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart	[reply]
Re^2: Sorting Outline Numbers by salva (Canon) on Aug 11, 2005 at 12:42 UTC
using Sort::Key it becomes even simpler (and faster?): `use Sort::Key qw(keysort); @sorted = keysort { join('', map chr, split /\./) } @data;` [download]	[reply] [d/l]
Re^3: Sorting Outline Numbers by japhy (Canon) on Aug 11, 2005 at 14:19 UTC
I'm assuming that's producing a Schwartzian Transform. The benefit of the Guttman-Rosler Transform (which I've employed) is that it uses 'sort' instead of 'sort { ... }'. However, speed really isn't an issue here (nor should it be). Jeff `japhy` Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and `perl` hacker How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart	[reply]
Re^4: Sorting Outline Numbers by salva (Canon) on Aug 11, 2005 at 14:31 UTC
I'm assuming that's producing a Schwartzian Transform. No, Sort::Key is implemented in C so it doesn't have to use nasty tricks to avoid calling perl code inside the sorting algorithm. And it is faster than the GRT most of the times.	[reply]