Hi there, I've just started using Chart::Gnuplot and I'm having a problem where it's stacking all my time series data points at midnight versus spreading that data out across the day. It's seems like it doesn't recognize the H:M:S portion of the date I'm feeding it? I'm reading date/price values out of a MySQL table (from TIMESTAMP and INTEGER columns) and then plotting them out. The code looks like this... 
$query = "SELECT distinct date, priceInCents FROM META_VAL WHERE date 
+>= DATE_SUB(NOW(), INTERVAL 7 DAY) ORDER BY date ASC";
$sth = $dbh->prepare($query);
$sth->execute or die "SQL Error: $DBI::errstr\n";

while (my @result = $sth->fetchrow_array) {
    push @dates,  $result[0];
    push @prices, ($result[1]/100);
}

my $mygraph = Chart::Gnuplot->new(
    output       => "chart.png",
    timeaxis     => 'x',
    xlabel       => 'Date',
    ylabel       => 'Price',
}
my $data = Chart::Gnuplot::DataSet->new(
    xdata   => \@dates,
    ydata   => \@prices,
    style   => 'linespoints',
    timefmt => '%Y-%m-%d $H:%M:%S',      # input time format
);
$mygraph->plot2d($data);

[download]
...and some sample data looks like this... 
2015-03-02 10:09:00         4615 
2015-03-02 20:22:00         4645 
2015-03-03 10:30:00         4610 
2015-03-03 20:36:00         4625 
2015-03-04 10:43:00         4603 
2015-03-04 20:49:00         4790 
2015-03-05 10:54:00         4724 
2015-03-05 20:54:00         4834

[download]
...but like I said, the graph that is created has "islands" of points at midnight with no data points in between (like a normal stock price chart). I feel like I'm missing something obvious but my Google searches and Perl Monks searches haven't yielded anything. Cheers and thanks!

In reply to Chart::Gnuplot stacking data at midnight? by gadbermd

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