QuickPlots

quickplots is a lightweight, object-oriented plotting library for Python. It currently supports line charts.

Example

>>> import quickplots
>>> chart = quickplots.line((0, 0), (1, 1), (2, 4), (3, 9), name="squares")
>>> chart.get_series_by_name("squares").color("#FF0000")
>>> chart.create().save("chart.svg")

Installing

pip

quickplots can be installed using pip:

$ pip install quickplots

quickplots is written for Python 3. If the above installation fails, it may be that your system uses pip for the Python 2 version - if so, try:

$ pip3 install quickplots

Requirements

quickplots relies on OmniCanvas for its graphics capabilities. If you install quickplots using pip this library will be installed automatically. It also requires numerus.

Otherwise quickplots has no external dependencies, and is pure Python.

Overview

Creating Charts

The easiest way to create a chart is with the quick-add functions. For example, the following code would create a line chart of the sine function:

>>> import quickplots
>>> from math import sin, radians
>>> data = [(x, sin(radians(x))) for x in range(360)]
>>> chart = quickplots.line(*data, color="#0000FF", title="sin(x)")
>>> chart.x_label("angle")
>>> chart.y_label("sine of angle")

A few things to note here. The line function takes (x, y) data points as its positional arguments - these can be lists or tuples. All arguments that are not data must be given as keyword arguments.

As with all other quickplots functions that accept data in this way, you can also provide the data in the form of two lists (or tuples) - one of all the x values and one of all the y values:

>>> chart = quickplots.line([x for x in range(360)], [sin(radians(x)) for x in range(360)])

Line charts

Use the line function as above to create line charts. You can pass in hex colors to the color function and line styles (see the full documentation for a full list of styles) to the linestyle argument.

Charts themselves also have a charts.AxisChart.line method for adding new line series. To add the cosine function to the above chart, you would do the following:

>>> cosine_data = [(x, cos(radians(x))) for x in range(360)]
>>> chart.line(*cosine_data, color="#00FF00")

Scatter charts

scatter() will create a scatter chart. You can set the size of the points with the size argument, as well as their color and linewidth (the width of the points' border).

Charts themselves also have a scatter() method for adding new line series. To add the cosine function to the above chart, you would do the following:

>>> cosine_data = [(x, cos(radians(x))) for x in range(360)]
>>> chart.scatter(*cosine_data, color="#00FF00")

Modifying Charts

Charts have a title, an x axis label, and a y axis label, which can be modified like so:

>>> chart.title()
'sin(x)'
>>> chart.title("A new title")
>>> chart.title()
'A new title'
>>> chart.x_label("A new x-axis label")
>>> chart.y_label("A new y-axis label")

Ticks will be automatically generated, but if you want to specify your own you can specify your own:

>>> chart.x_ticks(0, 90, 180, 270, 360)
>>> chart.x_ticks()
(0, 90, 180, 270, 360)

Charts can have one or more Series` objects. The ``series` property will return the first series, and the all_series will return all the series on the chart.

See the documentation for AxisChart for more information.

Outputting Charts

All charts have a create method which will create an OmniCanvas canvas with the chart painted to it. These can be saved or rendered as SVG text.

>>> chart.create()
<Canvas 700×500 (7 Graphics)>
>>> chart.create().save("Charts.svg")

Changelog

Release 2.1.0

5 February 2017

• Added Scatter series for scatter plots.
• Charts now have ticks and grid lines.
• Added new colour palette and colour generation.
• Line charts can now set the width of their line.

Release 2.0.0

9 January 2017

• Remade quickplots as dependent on OmniCanvas for its graphics rendering.
• Added LineSeries and AxisCharts.
• Added quick-add function for easy creation of line charts.