# phpman > perldoc > Spreadsheet::WriteExcel::Chart

## NAME
    Chart - A writer class for Excel Charts.

## SYNOPSIS
    To create a simple Excel file with a chart using [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown):

        #!/usr/bin/perl -w

        use strict;
        use [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown);

        my $workbook  = [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown)->new( 'chart.xls' );
        my $worksheet = $workbook->add_worksheet();

        my $chart     = $workbook->add_chart( type => 'column' );

        # Configure the chart.
        $chart->add_series(
            categories => '=Sheet1!$A$2:$A$7',
            values     => '=Sheet1!$B$2:$B$7',
        );

        # Add the worksheet data the chart refers to.
        my $data = [
            [ 'Category', 2, 3, 4, 5, 6, 7 ],
            [ 'Value',    1, 4, 5, 2, 1, 5 ],
        ];

        $worksheet->write( 'A1', $data );

        __END__

## DESCRIPTION
    The "Chart" module is an abstract base class for modules that implement charts in
    [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown). The information below is applicable to all of the available subclasses.

    The "Chart" module isn't used directly, a chart object is created via the Workbook "add_chart()"
    method where the chart type is specified:

        my $chart = $workbook->add_chart( type => 'column' );

    Currently the supported chart types are:

    *   "area": Creates an Area (filled line) style chart. See [Spreadsheet::WriteExcel::Chart::Area](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel%3A%3AChart%3A%3AArea/markdown).

    *   "bar": Creates a Bar style (transposed histogram) chart. See
        [Spreadsheet::WriteExcel::Chart::Bar](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel%3A%3AChart%3A%3ABar/markdown).

    *   "column": Creates a column style (histogram) chart. See
        [Spreadsheet::WriteExcel::Chart::Column](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel%3A%3AChart%3A%3AColumn/markdown).

    *   "line": Creates a Line style chart. See [Spreadsheet::WriteExcel::Chart::Line](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel%3A%3AChart%3A%3ALine/markdown).

    *   "pie": Creates an Pie style chart. See [Spreadsheet::WriteExcel::Chart::Pie](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel%3A%3AChart%3A%3APie/markdown).

    *   "scatter": Creates an Scatter style chart. See [Spreadsheet::WriteExcel::Chart::Scatter](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel%3A%3AChart%3A%3AScatter/markdown).

    *   "stock": Creates an Stock style chart. See [Spreadsheet::WriteExcel::Chart::Stock](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel%3A%3AChart%3A%3AStock/markdown).

    More charts and sub-types will be supported in time. See the "TODO" section.

    Methods that are common to all chart types are documented below.

## CHART METHODS
  add_series()
    In an Excel chart a "series" is a collection of information such as values, x-axis labels and
    the name that define which data is plotted. These settings are displayed when you select the
    "Chart -> Source Data..." menu option.

    With a [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown) chart object the "add_series()" method is used to set the
    properties for a series:

        $chart->add_series(
            categories    => '=Sheet1!$A$2:$A$10',
            values        => '=Sheet1!$B$2:$B$10',
            name          => 'Series name',
            name_formula  => '=Sheet1!$B$1',
        );

    The properties that can be set are:

    *   "values"

        This is the most important property of a series and must be set for every chart object. It
        links the chart with the worksheet data that it displays. Note the format that should be
        used for the formula. See "Working with Cell Ranges".

    *   "categories"

        This sets the chart category labels. The category is more or less the same as the X-axis. In
        most chart types the "categories" property is optional and the chart will just assume a
        sequential series from "1 .. n".

    *   "name"

        Set the name for the series. The name is displayed in the chart legend and in the formula
        bar. The name property is optional and if it isn't supplied will default to "Series 1 .. n".

    *   "name_formula"

        Optional, can be used to link the name to a worksheet cell. See "Chart names and links".

    You can add more than one series to a chart, in fact some chart types such as "stock" require
    it. The series numbering and order in the final chart is the same as the order in which that are
    added.

        # Add the first series.
        $chart->add_series(
            categories => '=Sheet1!$A$2:$A$7',
            values     => '=Sheet1!$B$2:$B$7',
            name       => 'Test data series 1',
        );

        # Add another series. Category is the same but values are different.
        $chart->add_series(
            categories => '=Sheet1!$A$2:$A$7',
            values     => '=Sheet1!$C$2:$C$7',
            name       => 'Test data series 2',
        );

  set_x_axis()
    The "set_x_axis()" method is used to set properties of the X axis.

        $chart->set_x_axis( name => 'Sample length (m)' );

    The properties that can be set are:

    *   "name"

        Set the name (title or caption) for the axis. The name is displayed below the X axis. This
        property is optional. The default is to have no axis name.

    *   "name_formula"

        Optional, can be used to link the name to a worksheet cell. See "Chart names and links".

    Additional axis properties such as range, divisions and ticks will be made available in later
    releases. See the "TODO" section.

  set_y_axis()
    The "set_y_axis()" method is used to set properties of the Y axis.

        $chart->set_y_axis( name => 'Sample weight (kg)' );

    The properties that can be set are:

    *   "name"

        Set the name (title or caption) for the axis. The name is displayed to the left of the Y
        axis. This property is optional. The default is to have no axis name.

    *   "name_formula"

        Optional, can be used to link the name to a worksheet cell. See "Chart names and links".

    Additional axis properties such as range, divisions and ticks will be made available in later
    releases. See the "TODO" section.

  set_title()
    The "set_title()" method is used to set properties of the chart title.

        $chart->set_title( name => 'Year End Results' );

    The properties that can be set are:

    *   "name"

        Set the name (title) for the chart. The name is displayed above the chart. This property is
        optional. The default is to have no chart title.

    *   "name_formula"

        Optional, can be used to link the name to a worksheet cell. See "Chart names and links".

  set_legend()
    The "set_legend()" method is used to set properties of the chart legend.

        $chart->set_legend( position => 'none' );

    The properties that can be set are:

    *   "position"

        Set the position of the chart legend.

            $chart->set_legend( position => 'none' );

        The default legend position is "bottom". The currently supported chart positions are:

            none
            bottom

        The other legend positions will be added soon.

  set_chartarea()
    The "set_chartarea()" method is used to set the properties of the chart area. In Excel the chart
    area is the background area behind the chart.

    The properties that can be set are:

    *   "color"

        Set the colour of the chart area. The Excel default chart area color is 'white', index 9.
        See "Chart object colours".

    *   "line_color"

        Set the colour of the chart area border line. The Excel default border line colour is
        'black', index 9. See "Chart object colours".

    *   "line_pattern"

        Set the pattern of the of the chart area border line. The Excel default pattern is 'none',
        index 0 for a chart sheet and 'solid', index 1, for an embedded chart. See "Chart line
        patterns".

    *   "line_weight"

        Set the weight of the of the chart area border line. The Excel default weight is 'narrow',
        index 2. See "Chart line weights".

    Here is an example of setting several properties:

        $chart->set_chartarea(
            color        => 'red',
            line_color   => 'black',
            line_pattern => 2,
            line_weight  => 3,
        );

    Note, for chart sheets the chart area border is off by default. For embedded charts this is on
    by default.

  set_plotarea()
    The "set_plotarea()" method is used to set properties of the plot area of a chart. In Excel the
    plot area is the area between the axes on which the chart series are plotted.

    The properties that can be set are:

    *   "visible"

        Set the visibility of the plot area. The default is 1 for visible. Set to 0 to hide the plot
        area and have the same colour as the background chart area.

    *   "color"

        Set the colour of the plot area. The Excel default plot area color is 'silver', index 23.
        See "Chart object colours".

    *   "line_color"

        Set the colour of the plot area border line. The Excel default border line colour is 'gray',
        index 22. See "Chart object colours".

    *   "line_pattern"

        Set the pattern of the of the plot area border line. The Excel default pattern is 'solid',
        index 1. See "Chart line patterns".

    *   "line_weight"

        Set the weight of the of the plot area border line. The Excel default weight is 'narrow',
        index 2. See "Chart line weights".

    Here is an example of setting several properties:

        $chart->set_plotarea(
            color        => 'red',
            line_color   => 'black',
            line_pattern => 2,
            line_weight  => 3,
        );

## WORKSHEET METHODS
    In Excel a chart sheet (i.e, a chart that isn't embedded) shares properties with data worksheets
    such as tab selection, headers, footers, margins and print properties.

    In [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown) you can set chart sheet properties using the same methods that are
    used for Worksheet objects.

    The following Worksheet methods are also available through a non-embedded Chart object:

        get_name()
        activate()
        select()
        hide()
        set_first_sheet()
        protect()
        set_zoom()
        set_tab_color()

        set_landscape()
        set_portrait()
        set_paper()
        set_margins()
        set_header()
        set_footer()

    See [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown) for a detailed explanation of these methods.

## EXAMPLE
    Here is a complete example that demonstrates some of the available features when creating a
    chart.

        #!/usr/bin/perl -w

        use strict;
        use [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown);

        my $workbook  = [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown)->new( 'chart_area.xls' );
        my $worksheet = $workbook->add_worksheet();
        my $bold      = $workbook->add_format( bold => 1 );

        # Add the worksheet data that the charts will refer to.
        my $headings = [ 'Number', 'Sample 1', 'Sample 2' ];
        my $data = [
            [ 2, 3, 4, 5, 6, 7 ],
            [ 1, 4, 5, 2, 1, 5 ],
            [ 3, 6, 7, 5, 4, 3 ],
        ];

        $worksheet->write( 'A1', $headings, $bold );
        $worksheet->write( 'A2', $data );

        # Create a new chart object. In this case an embedded chart.
        my $chart = $workbook->add_chart( type => 'area', embedded => 1 );

        # Configure the first series. (Sample 1)
        $chart->add_series(
            name       => 'Sample 1',
            categories => '=Sheet1!$A$2:$A$7',
            values     => '=Sheet1!$B$2:$B$7',
        );

        # Configure the second series. (Sample 2)
        $chart->add_series(
            name       => 'Sample 2',
            categories => '=Sheet1!$A$2:$A$7',
            values     => '=Sheet1!$C$2:$C$7',
        );

        # Add a chart title and some axis labels.
        $chart->set_title ( name => 'Results of sample analysis' );
        $chart->set_x_axis( name => 'Test number' );
        $chart->set_y_axis( name => 'Sample length (cm)' );

        # Insert the chart into the worksheet (with an offset).
        $worksheet->insert_chart( 'D2', $chart, 25, 10 );

        __END__

## Chart object colours
    Many of the chart objects supported by [Spreadsheet::WriteExcl](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcl/markdown) allow the default colours to be
    changed. Excel provides a palette of 56 colours and in [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown) these colours are
    accessed via their palette index in the range 8..63.

    The most commonly used colours can be accessed by name or index.

        black   =>   8,    green    =>  17,    navy     =>  18,
        white   =>   9,    orange   =>  53,    pink     =>  33,
        red     =>  10,    gray     =>  23,    purple   =>  20,
        blue    =>  12,    lime     =>  11,    silver   =>  22,
        yellow  =>  13,    cyan     =>  15,
        brown   =>  16,    magenta  =>  14,

    For example the following are equivalent.

        $chart->set_plotarea( color => 10    );
        $chart->set_plotarea( color => 'red' );

    The colour palette is shown in "palette.html" in the "docs" directory of the distro. An Excel
    version of the palette can be generated using "colors.pl" in the "examples" directory.

    User defined colours can be set using the "set_custom_color()" workbook method. This and other
    aspects of using colours are discussed in the "Colours in Excel" section of the main
    [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown) documentation:
    <<http://search.cpan.org/dist/Spreadsheet-WriteExcel/lib/Spreadsheet/WriteExcel.pm#COLOURS_IN_EXC>
    EL>.

## Chart line patterns
    Chart lines patterns can be set using either an index or a name:

        $chart->set_plotarea( weight => 2      );
        $chart->set_plotarea( weight => 'dash' );

    Chart lines have 9 possible patterns are follows:

        'none'         => 0,
        'solid'        => 1,
        'dash'         => 2,
        'dot'          => 3,
        'dash-dot'     => 4,
        'dash-dot-dot' => 5,
        'medium-gray'  => 6,
        'dark-gray'    => 7,
        'light-gray'   => 8,

    The patterns 1-8 are shown in order in the drop down dialog boxes in Excel. The default pattern
    is 'solid', index 1.

## Chart line weights
    Chart lines weights can be set using either an index or a name:

        $chart->set_plotarea( weight => 1          );
        $chart->set_plotarea( weight => 'hairline' );

    Chart lines have 4 possible weights are follows:

        'hairline' => 1,
        'narrow'   => 2,
        'medium'   => 3,
        'wide'     => 4,

    The weights 1-4 are shown in order in the drop down dialog boxes in Excel. The default weight is
    'narrow', index 2.

## Chart names and links
    The add_series()), "set_x_axis()", "set_y_axis()" and "set_title()" methods all support a "name"
    property. In general these names can be either a static string or a link to a worksheet cell. If
    you choose to use the "name_formula" property to specify a link then you should also the "name"
    property. This isn't strictly required by Excel but some third party applications expect it to
    be present.

        $chart->set_title(
            name          => 'Year End Results',
            name_formula  => '=Sheet1!$C$1',
        );

    These links should be used sparingly since they aren't commonly used in Excel charts.

## Chart names and Unicode
    The add_series()), "set_x_axis()", "set_y_axis()" and "set_title()" methods all support a "name"
    property. These names can be UTF8 strings if you are using perl 5.8+.

        # perl 5.8+ example:
        my $smiley = "\x{263A}";

        $chart->set_title( name => "Best. Results. Ever! $smiley" );

    For older perls you write Unicode strings as UTF-16BE by adding a "name_encoding" property:

        # perl 5.005 example:
        my $utf16be_name = pack 'n', 0x263A;

        $chart->set_title(
            name          => $utf16be_name,
            name_encoding => 1,
        );

    This methodology is explained in the "UNICODE IN EXCEL" section of [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown) but
    is semi-deprecated. If you are using Unicode the easiest option is to just use UTF8 in perl
    5.8+.

## Working with Cell Ranges
    In the section on "add_series()" it was noted that the series must be defined using a range
    formula:

        $chart->add_series( values => '=Sheet1!$B$2:$B$10' );

    The worksheet name must be specified (even for embedded charts) and the cell references must be
    "absolute" references, i.e., they must contain "$" signs. This is the format that is required by
    Excel for chart references.

    Since it isn't very convenient to work with this type of string programmatically the
    [Spreadsheet::WriteExcel::Utility](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel%3A%3AUtility/markdown) module, which is included with [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown),
    provides a function called "xl_range_formula()" to convert from zero based row and column cell
    references to an A1 style formula string.

    The syntax is:

        xl_range_formula($sheetname, $row_1, $row_2, $col_1, $col_2)

    If you include it in your program, using the standard import syntax, you can use the function as
    follows:

        # Include the Utility module or just the function you need.
        use [Spreadsheet::WriteExcel::Utility](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel%3A%3AUtility/markdown) qw( xl_range_formula );
        ...

        # Then use it as required.
        $chart->add_series(
            categories    => xl_range_formula( 'Sheet1', 1, 9, 0, 0 ),
            values        => xl_range_formula( 'Sheet1', 1, 9, 1, 1 ),
        );

        # Which is the same as:
        $chart->add_series(
            categories    => '=Sheet1!$A$2:$A$10',
            values        => '=Sheet1!$B$2:$B$10',
        );

    See [Spreadsheet::WriteExcel::Utility](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel%3A%3AUtility/markdown) for more details.

## TODO
    Charts in [Spreadsheet::WriteExcel](https://www.chedong.com/phpMan.php/perldoc/Spreadsheet%3A%3AWriteExcel/markdown) are a work in progress. More chart types and features will be
    added in time. Please be patient. Even a small feature can take a week or more to implement,
    test and document.

    Features that are on the TODO list and will be added are:

    *   Chart sub-types.

    *   Colours and formatting options. For now you will have to make do with the default Excel
        colours and formats.

    *   Axis controls, gridlines.

    *   3D charts.

    *   Embedded data in charts for third party application support. See Known Issues.

    *   Additional chart types such as Bubble and Radar. Send an email if you are interested in
        other types and they will be added to the queue.

    If you are interested in sponsoring a feature let me know.

## KNOWN ISSUES
    *   Currently charts don't contain embedded data from which the charts can be rendered. Excel
        and most other third party applications ignore this and read the data via the links that
        have been specified. However, some applications may complain or not render charts correctly.
        The preview option in Mac OS X is an known example. This will be fixed in a later release.

    *   When there are several charts with titles set in a workbook some of the titles may display
        at a font size of 10 instead of the default 12 until another chart with the title set is
        viewed.

    *   Stock (and other) charts should have the X-axis dates aligned at an angle for clarity. This
        will be fixed at a later stage.

## AUTHOR
    John McNamara <jmcnamara@cpan.org>

## COPYRIGHT
    Copyright MM-MMX, John McNamara.

    All Rights Reserved. This module is free software. It may be used, redistributed and/or modified
    under the same terms as Perl itself.