1Chart::Manual::Methods(U3s)er Contributed Perl DocumentatCihoanrt::Manual::Methods(3)
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6 Chart::Manual::Methods - user API
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9 This are all methods for the chart user.
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12 add_datafile
13 Loads all data of a chart (one or more data sets) from a file. (Works
14 only if no data yet added.) You have to either provide a filename or
15 filehandle (OLD_SCHOOL or $scalar).
16 $graph->add_dataset( 'file.tsv' );
18 $graph->add_dataset( $file_handle );
19 $graph->add_dataset( FILE_HANDLE );
20 An optional second argument, which defaults to 'set' can change the
22 file format if set to 'pt'. In 'set' mode every row of the file content
23 is fed to "add_dataset", in 'pt' every row get loaded like via
24 "add_pt". In other words: 'pt' transposes the data table.
25 $graph->add_dataset( 'file.tsv', 'pt' );
27 The arbitrary named text files have to contain one or several rows of
29 numbers. The numbers need to be separated by spaces or tabs (\t)
30 (mixing allowed). Perl style comments or empty lines will be ignored,
31 but rows containing different amount of numbers will cause problems.
32 add_dataset
34 Adding a list of values as one data set. That is one row in the overall
35 data table. The first data set are usually x-axis labels (domain set).
36 Make sure all sets have the same length.
37 $graph->add_dataset( 1, 2, 3, ... );
39 $graph->add_dataset( [1, 2, 3, ...] );
40 For instances with Points, Lines or Bars one data set is represented by
42 a set of graphic items (points, bars or line) of one color.
43 add_pt
45 Adds (appends) to each already existing data set one value. That is a
46 column in the overall data table. In this example it adds to set 0 the
47 value 3, to set 1 the 6 and so forth. Make sure that the list lengths
48 matches the number of already existing data sets.
49 $graph->add_pt( 3, 6, 9, ... );
51 $graph->add_pt( [3, 6, 9, ...] );
52 cgi_jpeg
54 Creates same JPEG image as "jpeg", but outputs to STDOUT. Since no file
55 name or handle needed, only the optional data argument is acceptable.
56 $graph->cgi_jpeg( );
58 my @data = ([1, 2, 3], # data set 0
60 [3, 4, 5]); # data set 1
61 $graph->cgi_jpeg( \@data );
62 cgi_png
64 Creates same PNG image as "png", but outputs to STDOUT. Since no file
65 name or handle needed, only the optional data argument is acceptable.
66 $graph->cgi_png( );
68 my $data = [[1, 2, 3], # data set 0
70 [3, 4, 5] ]; # data set 1
71 $graph->cgi_png( $data );
72 clear_data
74 Needs no arguments and deletes all so far added data.
75 get_data
77 Return all data (array of arrays) given to a graph.
78 imagemap_dump
80 When creating a chart for web purposes by "cgi_jpeg" or "cgi_png", you
81 maybe want the information, where the areas of interests in the image
82 are located, that should react to a users click. (HTML tag map). These
83 areas are bounding boxes around the drawn bars or points. You will get
84 per box the values: x1, y1, x2, y2 in one array. These arrays are
85 again in an Array holding, all boxes from one data set. The highest
86 level array again holds all arrays of all data sets, beginning with
87 index 1.
88 This method can only be called, if the functionality is activated by
90 setting the property: imagemap to 'true'.
91 $graph->set( imagemap => 'true');
93 my $image_map = $graph->imagemap_dump();
94 say "coordinates of first bar, first data set:";
96 say for @{$image_map->[1][0]};
97 jpeg
99 Creates an JPEG image from given data and properties. Accepts a file
100 name or a file handle (raw or in a SCALAR). The method closes the file
101 handle.
102 $graph->jpeg( 'image.jpg' );
104 $graph->jpeg( $file_handle );
105 $graph->jpeg( FILE_HANDLE );
106 $graph->jpeg( 'image.jpg', $data );
108 $graph->jpeg( 'image.jpg', 'data_file.tsv' );
109 $graph->jpeg( 'image.jpg', $file_handle );
110 $graph->jpeg( 'image.jpg', FILE_HANDLE );
111 The second, optional argument is the data in form of an array of arrays
113 reference. This only works, if there is no data already given to the
114 object. Alternatively the data can also be loaded from a file, just
115 provide the filename or filehandle (modern in SCALAR or old school).
116 Read more about the file format at "add_datafile" and note that this
117 method has another option for loading transposed data tables.
118 new
120 Creates a new chart object. Takes two optional arguments, which are the
121 width and height of the to be produced image in pixels. Defaults for
122 that are 400 x 300.
123 my $graph = Chart::Bars->new ( );
125 my $graph = Chart::Bars->new (600, 700);
126 Instead of Bars, you can also use: Composite, Direction, ErrorBars,
128 HorizontalBars, Lines, LinesPoints, Mountain, Pareto, Pie, Points,
129 Split and StackedBars. To know more about them read
130 Chart::Manual::Types.
131 png
133 Creates an PNG image from given data and properties. Accepts a file
134 name or a file handle (raw or in a SCALAR). The method closes the file
135 handle.
136 $graph->png( 'image.png' );
138 $graph->png( $file_handle );
139 $graph->png( FILE_HANDLE );
140 $graph->png( 'image.png', $data );
142 $graph->png( 'image.png', 'data_file.tsv' );
143 $graph->png( 'image.png', $file_handle );
144 $graph->png( 'image.png', FILE_HANDLE );
145 The second, optional argument is the data in form of an array of arrays
147 reference. This only works, if there is no data already given to the
148 object. Alternatively the data can also be loaded from a file, just
149 provide the filename or filehandle (modern in SCALAR or old school).
150 Read more about the file format at "add_datafile" and note that this
151 method has another option for loading transposed data tables.
152 scalar_jpeg
154 Creates same JPEG image as "jpeg" but returns the image binary into a
155 variable, not to STDOUT or a file.
156 my $image_binary = $graph->scalar_jpeg();
158 my $image_binary = $graph->scalar_jpeg( $data );
159 scalar_png
161 Creates same PNG image as "png" but returns the image binary into a
162 variable, not to STDOUT or a file.
163 my $image_binary = $graph->scalar_png();
165 my $image_binary = $graph->scalar_png( $data );
166 set
168 Method to change one or more chart properties in hash form.
169 $chart->set ( property_name => 'new value', ... );
171 $chart->set ( %properties );
172 Different chart types react to different properties, which are all
174 listed and explained under Chart::Manual::Properties.
175
177 Copyright 2022 Herbert Breunung.
178 This program is free software; you can redistribute it and/or modify it
180 under same terms as Perl itself.
181
183 Herbert Breunung, <lichtkind@cpan.org>
184perl v5.38.0 2023-07-20 Chart::Manual::Methods(3)