1Chart::Manual::WorkflowUss(e3r)Contributed Perl DocumentCahtairotn::Manual::Workflows(3)
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NAME

6       Chart::Manual::Workflows - different ways to create charts
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OVERVIEW

9       Four of the five major steps in creating a chart image are fixed in
10       their order. First you have to load the module, secondly create create
11       the object.  After that you
12        may change some properties.  And always as a last step you create the
13       image, no matter if the output goes to STDOUT or into a file.
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15       The only flexibility lies in how you prefer to provide the data.  And
16       here you have three options. Most commonly you add one data set at the
17       time, which could be also understood as a row of the complete data
18       table.  Second option is to build the table column by column. Thirdly
19       you can drop the complete table at once, either by reference to a data
20       structure or a file containing the data.  The last option is  closed if
21       you already given the object data.  It is not advisable to reuse a
22       chart object for further image creation outside of modern art projects.
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STEPS

25       Most steps are already explained elsewhere and the OVERVIEW just links
26       there. The missing bits are layed out here.
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28   use Chart
29       As with any other Modul you have to:
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31         use Chart::[Type];
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33       Type being a placeholder for a name of a chart type, which are: Bars,
34       Composite, Direction, ErrorBars, HorizontalBars, Lines, LinesPoints,
35       Mountain, Pareto, Pie, Points, Split, StackedBars. To know more about
36       them read Chart::Manual::Types.
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38       Alternatively write to load all chart types at ones with
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40         use Chart;
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42       Both are not importing any symbols in your name space but load Carp and
43       GD.
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45   drop data
46       All the methods listed in the last section, that create the final
47       image, take as an optional, second argument data.  This data may be
48       delivered either as a reference to an array of arrays:
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50           my $data = [ [ 1, 4, 3 ... ], # data set 0
51                        [ 5, 8, 2 ... ], # data set 1
52                        ...
53           ];
54           $graph->png( 'file.png', $data );
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56       or in form of a file. Then the argument has to be a file name or a file
57       handle (old school as in "FILE" or modern as in $FH).  Alternatively
58       use the method add_datafile.
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60   data files
61       Are arbitrary named text files containing one or several rows of
62       numbers, which have to be separated by spaces or tabs (\t) (mixing
63       allowed).  Perl style comments or empty lines will be ignored, but rows
64       containing different amount of numbers will cause problems.
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66   create image
67       Currently we support only images in the PNG and JPEG format. The
68       methods to create them are named straight forwardly: ->png and ->jpeg.
69       Both take the same arguments and produce image files. For shell
70       scripting or web programming you need the image binary, which you get
71       with: ->cgi_png or ->cgi_jpeg. Some users might even want the GD object
72       for further processing by your perl programm. In that case please use:
73       ->scalar_png or ->scalar_jpeg.
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75       After having created a chart for web purposes, you also might want to
76       utilize imagemap_dump.
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79       Copyright 2022 Herbert Breunung.
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81       This program is free software; you can redistribute it and/or modify it
82       under same terms as Perl itself.
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AUTHOR

85       Herbert Breunung, <lichtkind@cpan.org>
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89perl v5.36.0                      2022-08-01       Chart::Manual::Workflows(3)
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