Conal has asked for the wisdom of the Perl Monks concerning the following question:

This script runs twice every hour at both 00mins15secs and 30mins15secs. I am trying to select the nearest time before the 30min or 00min but NOT AFTER from an input file that can look like this. 
//SNAGIT.TXT eg top of the hour

1.29133 ,01:59:34 
1.29132 ,01:59:59 
1.29132 ,01:59:59
.....

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desired pair - 1.29132 ,01:59:59 
//SNAGIT.TXT e.g bottom of the hour

1.29020 ,01:29:52 
1.29036 ,01:30:02 
1.29035 ,01:30:12 
....

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desired pair - 1.29020 ,01:29:52

the code i have come up to achieve this is below, (i need the pattern matching regex to filter out dirty data.) 
use Time::ParseDate;
use Time::Local;
...

my ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdist) = localtime 
+time;
my $month = (qw(Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec)) [(lo
+caltime)[4]];
my $day = (Sun,Mon,Tue,Wed,Thu,Fri,Sat)[(localtime)[6]];
$year = $year+1900;

my $input = "SNAGIT.txt"; 
my $actualquote1=0;

## Open the SNAGIT.TXT, plus some sensible error checking

open(DATAFILE, "$input") || die("Can't open $input:!\n");

## Loop through the file one line at a time
while (<DATAFILE>) 
{
    chomp;
    if ( m{^ (\d\.\d{5}) \s*,\s* (\d\d:\d\d:\d\d) \s* (.*) $ }x ) 
    ## 1.XXXXX
    {
       
    my ( $quote, $linetime, $comment ) = ( $1, $2, $3 ); # captures
    my ( $snaghour, $snagminute, $snagsecond ) = split /:/, $linetime;
+              
    chop($quote);
                                                            
    if (parsedate($snaghour.":".$snagminute.":".$snagsecond) <= parsed
+ate($hour.":".$min.":00"))
        { $actualquote1 = $quote; }
                 
    }
                                
}

close(DATAFILE);

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Now my problem is; The code works great when the script runs on the 30minute, $actualquote gets assigned as it should.

The issue is the 00 script run, $actualquote never gets assigned the value i would expect, it remains assigned to 0.

can anyone suggest what the issue is?

i have mulled over this problem for a while and came up with a really ugly hacked solution previously.

I am rewriting my code now and i am sure this type of approach is cleaner.

thanks for reading and i hope i make some sense.
conal.

Replies are listed 'Best First'.
Re: Time::ParseDate issues
by eye (Chaplain) on Nov 27, 2008 at 07:06 UTC
    When the script runs at the top of the hour ("00"), the value for $min is 0. Have you verified that parsedate() isn't bothered by a time that looks like "2:0:00"?

    In any case, this: 

    parsedate($hour.":".$min.":00")

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    could be replaced with $now after adding the following lines before the while: 
    my $now = time;
$now -= ($now % 60);

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[d/l]
[select]
      The parsedate function will return undef value, if the time format is not correct.
      The time format is hh:mm:ss.
      You can add the digit zero in front of hour and minute.
      You can use the following code: 
      $min = "0".$min if(length($min) == 1);
$hour= "0".$hour if(length($hour) == 1);

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[d/l]
      hi eye, thanks for replying with this. i have tried a number of solutions here and yours seems the most likely. fixing up $hour and $min so it is in a format that doesnt make Parsedate return undef still produces an issue at 00:00:00. i have a problem tho, what is this code doing exactly and why does it work? 
      my $now = time;
$now -= ($now % 60);

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      and also would it work if i wanted to run my code every 5minutes with similar data, as opposed to 30minutes? thanks for your input and sorry to be a pain.
      conal.
[reply]
[d/l]
        parsedate($hour.":".$min.":00"))

        should give the same number of seconds,(since Jan 1, 1970), as:

        my $now = time;
$now -= ($now % 60);

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        I say should because I don't know if the function parsedate gives seconds since the epoch when only supplied the time numbers (and not the date numbers).

        What his code is doing is removing any seconds (> 00)

        Chris

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[d/l]
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Re: Time::ParseDate issues
by Anonymous Monk on Nov 27, 2008 at 03:31 UTC
    The issue is the 00 script run, $actualquote never gets assigned the value i would expect, it remains assigned to 0.
    can anyone suggest what the issue is?
    Add this to your code 
    ...
chomp;
warn "
\$_ ($_)
";

...

warn "

\$quote ($quote)
\$linetime ($linetime)
\$comment ($comment) 

";

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[reply]
[d/l]

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