Re: search through hash for date in a range

If the timestamp formats are always the same and governed by the category, you can use a simpler module to handle the conversions and specify the formats explicitly:

use Time::Piece;

my @vkeys;
my %ranges_dt;

# ==================================================
sub check_date_in_range
{
    my ($value, %h) = @_;
    my $cvalue = Time::Piece->strptime($value, '%m/%d/%Y-%H:%M:%S')->e
+poch;
    if (!@vkeys) {
        @vkeys = sort keys %h;
    }
    foreach my $k (@vkeys) {
        if (($cvalue >= $h{$k}{start}) && ($cvalue <= $h{$k}{end})) {
            return $k;
        }
    }
    return;
}

while (<DATA>) {
    chomp;
    if (s/^(\w+)://) {
        my $cat = $1;
        if ($cat eq "R") {
            my ($i, $s, $e) = split ',';
            $ranges_dt{$i}{start} = Time::Piece->strptime($s, '%Y-%m-%
+d %H:%M:%S')->epoch;
            $ranges_dt{$i}{end} = Time::Piece->strptime($e, '%Y-%m-%d 
+%H:%M:%S')->epoch;
        } else {
            my $rangeid = check_date_in_range($_, %ranges_dt);
            if (!defined $rangeid) {
                print "No range found for $_\n";
            } else {
                print "Found range: $rangeid\n";
            }
        }
    }
}
[download]

Another option would be not to store the timestamps in a hash and sort them every time a new one arrives, but use a data structure that can add a new element and quickly search for the closest members (binary search tree, for example).

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
[download]

Comment on Re: search through hash for date in a range Select or Download Code

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Re^2: search through hash for date in a range by bfdi533 (Friar) on Mar 06, 2018 at 18:46 UTC
Boy, there is a huge difference in performance between Date::Manip::Date and Time::Piece ... `[user@host newload]$ ./t-benchdates.pl 500 Benchmark: timing 500 iterations of Date::Manip::Date, Time::Piece... Date::Manip::Date: 124 wallclock secs (119.35 usr + 1.30 sys = 120.65 + CPU) @ 4.14/s (n=500) Time::Piece: 5 wallclock secs ( 3.88 usr + 0.03 sys = 3.91 CPU) @ 1 +27.88/s (n=500)` [download] Certainly a code change I will be making but that leaves the foreach loop through all available ranges as a massive performance hit still ...	[reply] [d/l]
Re^2: search through hash for date in a range by bfdi533 (Friar) on Mar 06, 2018 at 18:21 UTC
I assume your recommendation for Time::Piece is due to better performance? Otherwise, not sure why I would change libraries from something I know works. As to sorting the keys each time, I already reduced that workload to a cached array with the code: `if (!@vkeys) { @vkeys = sort keys %h; }` [download] Only one sort is being done the first time the sub is run ...	[reply] [d/l]