A set of sparkline-ish widgets for urwid.

This module contains a set of urwid text-like widgets for creating tiny but hopefully useful sparkline-like visualizations of data using unicode block elements.

Currently consists of two widgets:

• SparkColumnWidget is a column chart. Segments can be explicitly given urwid display attributes, or can be assigned colors and other attributes according to a rotating color scheme or based on rules (e.g. negative values in red). By default the Y-axis scales to fit all values, but minimum and maximum values for the Y-axis scale can also be provided -- this might not seem useful given the extremely limited resolution of these tiny charts (only eight possible block elements) but makes sense if you want to use mulitple sparklines with the same scale to show differences in values between them.

• SparkBarWidget is a stacked horizontal bar chart. It will fill a text widget of a given width with colored segments for each input value. It supports the same color scheme functionality as the column widget.

TODOs:

• Allow for user-defined character schemes for the bar widget. Unicode block elements are most useful for increasing the resolution of the chart over typical ASCII block art, but it'd be nice to be able to do something like ******@@@@@@@@#####%%%% for compatibility with non-color displays.
• Support log scale.
• Labels in bar chart?

Here are some examples of what the charts look like: