in reply to Re^5: How can I do a numeric sort on a substring? (context matters)
in thread How can I do a numeric sort on a substring?

++ Many thanks for tracking down the problem. Much appreciated.

The results are now more in line with what I would have expected. I see that Perl's string handling function, substr, outstrips the regex solutions: I have been recommending, for a very long time, that string functions be chosen over regexes (where they provide equivalent functionality).

I should probably add some ST routines (e.g. STss, STmcs) to see how they fare; for instance, would GRTpe be faster than STss. I'm currently at $work, so I can't do that now; I'll look into it this evening (i.e. ~8-10hrs hence).

— Ken

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Re^7: How can I do a numeric sort on a substring? [Benchmark: reworked and extended]
by kcott (Archbishop) on Jun 28, 2021 at 08:21 UTC

    I wrapped all of the routines in @{[...]} to provide the list context; that was what I'd used in the preamble tests.

    I added an STss as I had indicated this morning. I decided that STmcs was going to be pretty much the same as STss, so I skipped that one. I did add an mcse which was mcs with map BLOCK replaced by map EXPR. 

    sub st_sort_substr {
    @{[
        map $_->[0],
        sort {
            $a->[1] <=> $b->[1]
        }
        map [$_, substr $_, 2], @unordered
    ]};
}

sub map_cat_substr_expr {
    @{[
        map "a-$_",
        sort {
            $a <=> $b
        }
        map substr($_, 2), @unordered
    ]};
}

    [download]

    I saw ++swl's post. There wasn't any code there, so I guessed. 

    use Sort::Key 'ikeysort';
use Sort::Key::Natural 'natsort';
...
sub sort_key_integer {
    @{[
        ikeysort { substr $_, 2 } @unordered
    ]};
}

sub sort_key_natural {
    @{[
        natsort @unordered
    ]};
}

    [download]

    I ran the benchmark several times; there were no major differences between runs. Here's a sample output, in the spoiler; it's getting very wide (18 subroutines now) and this post is "Re^7", so probably best viewed via the "download" link.

    <Reveal this spoiler or all spoilers in this node or all in this thread>

    And here's the code:

    <Reveal this spoiler>

    — Ken

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      Not providing the code is a fairly egregious oversight on my part. Apologies for that.

      Your usage is the same as mine, but my code is in the spoiler for completeness.

      <Reveal this spoiler or all in this thread>
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