First steps¶

Caution

First you need to install pygal, see installing.

When it’s done, you are ready to make your first chart:

import pygal                                                       # First import pygal
bar_chart = pygal.Bar()                                            # Then create a bar graph object
bar_chart.add('Fibonacci', [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55])  # Add some values
bar_chart.render_to_file('bar_chart.svg')                          # Save the svg to a file

Now you should have a svg file called bar_chart.svg in your current directory.

You can open it with various programs such as your web browser, inkscape or any svg compatible viewer.

The resulting chart will be tho following:

bar_chart = pygal.Bar()
bar_chart.add('Fibonacci', [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55])
bar_chart.render()

Caution

pygal relies on svg css styling. This is sadly not fully supported by gnome librsvg and therefore can lead to black svg being displayed. This is not a bug in pygal. See this bugzilla search

To make a multiple series graph just add another one:

bar_chart = pygal.Bar()
bar_chart.add('Fibonacci', [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55])
bar_chart.add('Padovan', [1, 1, 1, 2, 2, 3, 4, 5, 7, 9, 12])
bar_chart.render()

If you want to stack them, use StackedBar instead of Bar:

bar_chart = pygal.StackedBar()
bar_chart.add('Fibonacci', [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55])
bar_chart.add('Padovan', [1, 1, 1, 2, 2, 3, 4, 5, 7, 9, 12])
bar_chart.render()

You can also make it horizontal with HorizontalStackedBar:

bar_chart = pygal.HorizontalStackedBar()
bar_chart.add('Fibonacci', [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55])
bar_chart.add('Padovan', [1, 1, 1, 2, 2, 3, 4, 5, 7, 9, 12])
bar_chart.render()

And finally add a title and some labels:

bar_chart = pygal.HorizontalStackedBar()
bar_chart.title = "Remarquable sequences"
bar_chart.x_labels = map(str, range(11))
bar_chart.add('Fibonacci', [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55])
bar_chart.add('Padovan', [1, 1, 1, 2, 2, 3, 4, 5, 7, 9, 12])
bar_chart.render()