NAME

GD::Graph::candlesticks - GD::Graph type that shows open, high, low and close as "candlesticks"

SYNOPSIS

Create an chart, displaying the open, high, low, and close -- normally for stock data -- as candlesticks. The data points for candlestick charts are completely different from all the other graph types, they must be four tuples, [$o,$h,$l,$c], instead of single scalar values. See the "DATA" section for an explanation.

DATA

The data points for candlesticks and candlesticks-mixed graphs must be four tuples -- instead of the single scalar number the other GD::Graphs take. This would feed nicely into an candlesticks-mixed graph:

@data = (
    ['1st', '2nd', '3rd'],
    [ 1, 2, 3 ],
    [ [1,2,3,4], [1,2,3,4], [1,2,3,4] ],
);

NEW OPTION

This module adds a new option: candlestick_width (default: 7). It is the overall width of the candlestick. Candlesticks shouldn't touch the way bar-graphs would, so this seemed to require a new option.

EXAMPLE

This example turns out like this: https://voltar.org/PerlModules/candlesticks_example.png.

NOTE: You do can to use GD::Graph::mixed here. See GD::Graph::ohlc for an example that uses mixed.

use strict;
use warnings;
use List::Util qw(min max);
use GD::Graph::candlesticks;

my @msft = (     #  open       high       low        close
    ["2007/12/18", "34.6400", "35.0000", "34.2100", "34.7400"],
    ["2007/12/19", "34.6900", "35.1400", "34.3800", "34.7900"],
    ["2007/12/20", "35.2900", "35.7900", "35.0800", "35.5200"],
    ["2007/12/21", "35.9000", "36.0600", "35.7500", "36.0600"],
    ["2007/12/24", "36.1300", "36.7200", "36.0500", "36.5800"],
    ["2007/12/26", "36.4100", "36.6400", "36.2600", "36.6100"],
    ["2007/12/27", "36.3500", "36.5500", "35.9400", "35.9700"],
    ["2007/12/28", "36.1000", "36.2300", "35.6700", "36.1200"],
    ["2007/12/31", "35.9000", "35.9900", "35.5200", "35.6000"],
    ["2008/01/02", "35.7900", "35.9600", "35.0000", "35.2200"],
    ["2008/01/03", "35.2200", "35.6500", "34.8600", "35.3700"],
    ["2008/01/04", "35.1900", "35.2000", "34.0900", "34.3800"],
    ["2008/01/07", "34.5500", "34.8000", "34.2500", "34.6100"],
    ["2008/01/08", "34.7100", "34.7100", "33.4000", "33.4500"],
    ["2008/01/09", "33.3600", "34.5400", "33.3500", "34.4400"],
    ["2008/01/10", "34.3500", "34.5000", "33.7800", "34.3300"],
    ["2008/01/11", "34.1400", "34.2400", "33.7200", "33.9100"],
    ["2008/01/14", "34.4600", "34.5700", "34.0800", "34.3900"],
    ["2008/01/15", "34.0300", "34.3800", "34.0000", "34.0000"],
    ["2008/01/16", "33.4200", "33.6500", "32.5100", "33.2300"],
    ["2008/01/17", "33.5400", "33.8000", "32.9700", "33.1100"],
    ["2008/01/18", "33.1600", "34.0000", "32.9700", "33.0100"],
    ["2008/01/22", "31.5400", "32.5300", "31.5000", "31.9600"],
    ["2008/01/23", "31.4800", "32.0500", "31.0400", "31.9300"],
    ["2008/01/24", "32.3500", "33.3600", "32.1200", "33.2500"],
    ["2008/01/25", "34.9000", "35.0000", "32.8700", "32.9400"],
    ["2008/01/28", "33.0200", "33.1000", "32.4200", "32.7200"],
    ["2008/01/29", "32.8500", "32.8900", "32.3500", "32.6000"],
    ["2008/01/30", "32.5600", "32.8000", "32.0500", "32.2000"],
    ["2008/01/31", "31.9100", "32.7400", "31.7200", "32.6000"],
);

my @all_points = map {@$_[1 .. 4]} @msft;
my $min_point  = min(@all_points);
my $max_point  = max(@all_points);

my $graph = GD::Graph::candlesticks->new(800, 400);
   $graph->set( 
        x_labels_vertical => 1,
        x_label           => 'Trade Date',
        y_label           => 'NASDAQ:MSFT',
        title             => "Example OHLC",
        transparent       => 0,
        candlestick_width => 7,
        dclrs             => [qw(blue)],
        y_min_value       => $min_point-0.2,
        y_max_value       => $max_point+0.2,
        y_number_format   => '%0.2f',

    ) or warn $graph->error;

my $data_candlesticks = [
    [ map {$_->[0]} @msft ],       # date
    [ map {[@$_[1 .. 4]]} @msft ], # candlesticks
];

my $gd = $graph->plot($data_candlesticks) or die $graph->error;
open my $dump, ">candlesticks_example.png" or die $!;
print $dump $gd->png;
close $dump;

AUTHOR

Paul Miller <jettero@cpan.org>

I am using this software in my own projects... If you find bugs, please please please let me know. Actually, let me know if you find it handy at all. Half the fun of releasing this stuff is knowing that people use it.

If you see anything wrong with the callbacks, the docs, or anything: Definitely let me know! rt.cpan, irc, email, whatever. Just let me know.

THANKS

Nilson Santos Figueiredo Junior <nilsonsfj@cpan.org>

Noticed the candlesticks were upside down -- how did I miss that?

COPYRIGHT

Copyright (c) 2009 Paul Miller

SEE ALSO

perl(1), GD::Graph, GD::Graph::ohlc, http://en.wikipedia.org/wiki/Candlestick_chart, http://en.wikipedia.org/wiki/Error_bars