True. Of course, in this application, there appear to be a maximum of 24 possible entries...

Being curious, I did a quick benchmark. However, its results defy logic (my (sort grep keys)[-1] is always faster than a O(1) "max()" algorithm!)

Since I am obviously missing something, would you be willing to post some benchmarking code showing the efficiency differences between "sort" and "max()" in this context?

Russ

P.S. Just for the sake of helping me find my silliness, here is what I was running. Changing the map to larger numbers (to make the source hash bigger) made no difference to the benchmark times. 

#!/usr/bin/perl -w
use strict;
use Benchmark;
my $now = 8; # we'll pretend it's between 8 and 9 PM
my %url = (
  monday => {
    @{[map(($_,1), (1..1000))]}
  }
);
timethese(100000, {
  a => q{
    $now = (sort grep {$_ <= $now} keys %{$url{'monday'}})[-1];
  },
  b => q{
    $now = ($now < $_ && $_ < 8 ? $_ : $now) for keys %{$url{'monday'}
+};
  }
});

[download]
The results were the same even without doing the assignment each time in b (only assign when we should, rather than each time through the loop). I left it this way for no apparent reason...

In reply to RE:(3) Hash of hashes question by Russ
in thread Hash of hashes question by Ovid

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.