NAME¶
SVG::TT::Graph::XY - Create presentation quality SVG line graphs of XY data
points easily
SYNOPSIS¶
use SVG::TT::Graph::XY;
my @data_cpu = (0.3, 23, 0.5, 54, 1.0, 67, 1.8, 12);
my @data_disk = (0.45, 12, 0.51, 26, 0.53, 23);
my $graph = SVG::TT::Graph::XY->new({
'height' => '500',
'width' => '300',
});
$graph->add_data({
'data' => \@data_cpu,
'title' => 'CPU',
});
$graph->add_data({
'data' => \@data_disk,
'title' => 'Disk',
});
print "Content-type: image/svg+xml\n\n";
print $graph->burn();
DESCRIPTION¶
This object aims to allow you to easily create high quality SVG line graphs of
XY data. You can either use the default style sheet or supply your own. Either
way there are many options which can be configured to give you control over
how the graph is generated - with or without a key, data elements at each
point, title, subtitle etc.
METHODS¶
new()¶
use SVG::TT::Graph::XY;
my $graph = SVG::TT::Graph::XY->new({
# Optional - defaults shown
'height' => 500,
'width' => 300,
'show_y_labels' => 1,
'yscale_divisions' => '',
'min_yscale_value' => 0,
'max_yscale_value' => '',
'show_x_labels' => 1,
'xscale_divisions' => '',
'min_xscale_value' => '',
'max_xscale_value' => '',
'stagger_x_labels' => 0,
'rotate_x_labels' => 0,
'y_label_formatter' => sub { return @_ },
'x_label_formatter' => sub { return @_ },
'show_data_points' => 1,
'show_data_values' => 1,
'rollover_values' => 0,
'area_fill' => 0,
'show_x_title' => 0,
'x_title' => 'X Field names',
'show_y_title' => 0,
'y_title' => 'Y Scale',
'show_graph_title' => 0,
'graph_title' => 'Graph Title',
'show_graph_subtitle' => 0,
'graph_subtitle' => 'Graph Sub Title',
'key' => 0,
'key_position' => 'right',
# Stylesheet defaults
'style_sheet' => '/includes/graph.css', # internal stylesheet
'random_colors' => 0,
});
The constructor takes a hash reference with values defaulted to those shown
above - with the exception of style_sheet which defaults to using the internal
style sheet.
add_data()¶
my @data_cpu = (0.3, 23, 0.5, 54, 1.0, 67, 1.8, 12);
or
my @data_cpu = ([0.3,23], [0.5,54], [1.0,67], [1.8,12]);
or
my @data_cpu = ([0.3,23,'23%'], [0.5,54,'54%'], [1.0,67,'67%'], [1.8,12,'12%']);
$graph->add_data({
'data' => \@data_cpu,
'title' => 'CPU',
});
This method allows you to add data to the graph object. The data are expected to
be either a list of scalars (in which case pairs of elements are taken to be
X,Y pairs) or a list of array references. In the latter case, the first two
elements in each referenced array are taken to be X and Y, and the optional
third element (if present) is used as the text to display for that point for
show_data_values and rollover_values; otherwise the Y value itself is
displayed. It can be called several times to add more data sets in.
clear_data()¶
my $graph->clear_data();
This method removes all data from the object so that you can reuse it to create
a new graph but with the same config options.
burn()¶
print $graph->burn();
This method processes the template with the data and config which has been set
and returns the resulting SVG.
This method will croak unless at least one data set has been added to the graph
object.
config methods¶
my $value = $graph->method();
my $confirmed_new_value = $graph->method($value);
The following is a list of the methods which are available to change the config
of the graph object after it has been created.
- height()
- Set the height of the graph box, this is the total height of the SVG box
created - not the graph it self which auto scales to fix the space.
- width()
- Set the width of the graph box, this is the total width of the SVG box
created - not the graph it self which auto scales to fix the space.
- compress()
- Whether or not to compress the content of the SVG file (Compress::Zlib
required).
- tidy()
- Whether or not to tidy the content of the SVG file (XML::Tidy
required).
- style_sheet()
- Set the path to an external stylesheet, set to '' if you want to revert
back to using the default internal version.
The default stylesheet handles up to 12 data sets. All data series over the
12th will have no style and be in black. If you have over 12 data sets you
can assign them all random colors (see the random_color() method)
or create your own stylesheet and add the additional settings for the
extra data sets.
To create an external stylesheet create a graph using the default internal
version and copy the stylesheet section to an external file and edit from
there.
- random_colors()
- Use random colors in the internal stylesheet.
- show_data_values()
- Show the value of each element of data on the graph (or optionally a
user-defined label; see add_data).
- show_data_points()
- Show a small circle on the graph where the line goes from one point to the
next.
- rollover_values()
- Shows data values and data points when the mouse is over the point. Used
in combination with show_data_values and/or show_data_points.
- data_value_format()
- Format specifier to for data values (as per printf).
- max_x_span()
- Maximum span for a line between data points on the X-axis. If this span is
exceeded, the points are not connected. This is useful for skipping
missing data sections. If you set this value to something smaller than 0
(e.g. -1), you will get an XY scatter plot with no line joining the data
points.
- stacked()
- Accumulates each data set. (i.e. Each point increased by sum of all
previous series at same point). Default is 0, set to '1' to show.
- min_yscale_value()
- The point at which the Y axis starts, defaults to '0', if set to '' it
will default to the minimum data value.
- max_yscale_value()
- The point at which the Y axis ends, if set to '' it will default to the
maximum data value.
- yscale_divisions()
- This defines the gap between markers on the Y axis, default is a 10th of
the range, e.g. you will have 10 markers on the Y axis. NOTE: do not set
this too low - you are limited to 999 markers, after that the graph won't
generate.
- show_x_labels()
- Whether to show labels on the X axis or not, defaults to 1, set to '0' if
you want to turn them off.
- show_y_labels()
- Whether to show labels on the Y axis or not, defaults to 1, set to '0' if
you want to turn them off.
- y_label_format()
- Format string for presenting the Y axis labels (as per printf).
- xscale_divisions()
- This defines the gap between markers on the X axis. Default is the entire
range (only start and end axis labels).
- stagger_x_labels()
- This puts the labels at alternative levels so if they are long field names
they will not overlap so easily. Default it '0', to turn on set to
'1'.
- rotate_x_labels()
- This turns the X axis labels by 90 degrees. Default it '0', to turn on set
to '1'.
- min_xscale_value()
- This sets the minimum X value. Any data points before this value will not
be shown.
- max_xscale_value()
- This sets the maximum X value. Any data points after this value will not
be shown.
- show_x_title()
- Whether to show the title under the X axis labels, default is 0, set to
'1' to show.
- x_title()
- What the title under X axis should be, e.g. 'Parameter X'.
- show_y_title()
- Whether to show the title under the Y axis labels, default is 0, set to
'1' to show.
- y_title()
- What the title under Y axis should be, e.g. 'Sales in thousands'.
- show_graph_title()
- Whether to show a title on the graph, default is 0, set to '1' to
show.
- graph_title()
- What the title on the graph should be.
- show_graph_subtitle()
- Whether to show a subtitle on the graph, default is 0, set to '1' to
show.
- graph_subtitle()
- What the subtitle on the graph should be.
- key()
- Whether to show a key, defaults to 0, set to '1' if you want to show
it.
- key_position()
- Where the key should be positioned, defaults to 'right', set to 'bottom'
if you want to move it.
- x_label_formatter ()
- A callback subroutine which will format a label on the x axis. For
example:
$graph->x_label_formatter( sub { return '$' . $_[0] } );
- y_label_formatter()
- A callback subroutine which will format a label on the y axis. For
example:
$graph->y_label_formatter( sub { return '$' . $_[0] } );
EXAMPLES¶
For examples look at the project home page
http://leo.cuckoo.org/projects/SVG-TT-Graph/
EXPORT¶
None by default.
SEE ALSO¶
SVG::TT::Graph, SVG::TT::Graph::Line, SVG::TT::Graph::Bar,
SVG::TT::Graph::BarHorizontal, SVG::TT::Graph::BarLine, SVG::TT::Graph::Pie,
Compress::Zlib, XML::Tidy