blot

Blot is a plotting library written in C, that plots data onto a string buffer.

That's right, there are no images, just text -- see examples below.

Site: bartman.github.io/blot

GitHub: github.com/bartman/blot

Copyright © 2021 Bart Trojanowski

Licensed under LGPL v2.1, or any later version.

Noteworthy features

• plots to the console as text (by calling printf())
• very very fast (compared to python alternatives)
• very very memory usage friendly
• can plot multiple datasets on one canvas
• uses familiar figure based API (similar to existing python plotting frameworks)
• supports braille plotting (like plotille)
• 256 colour support
• data arrays can be provided in various types (int16, int32, int64, double, or float)

Prerequisites

blot was only tested on Debian Linux. It is built using standard tools.

sudo apt install make ninja-build cmake libglib2.0-dev

Building

blot is built using cmake and ninja. There is a top level Makefile only to simplify the build process (it invokes cmake in the build subdirectory).

make

Examples

blot is being used in other projects as a library, but it comes with some examples.

Generated from test-simple.c

./build/examples/test-simple

Generated from test-trig.c

./build/examples/test-trig

Missing features

• different plotting modes like bar and histograms (currently only plots line/scatter)
• improve axis line and numbering (currently not very accurate)
• add axis labels and minor ticks (configurable)
• draw origin lines and minor tick lines (configurable)

Ideas:

Allow for swapping data from layer to allow for even faster plotting (allow blot to reuse existing allocated structures)

1. create a figure
2. all blot_figure_scatter multiple times, have it return the blot_layer
3. call blot_figure_render and blot_screen_get_text
4. then use blot_layer_new_data to swap the data
5. repeat from step (3)

Similar projects

• plotille - Python, "plot, scatter plots and histograms in the terminal using braille dots"
• Tables-and-Graphs - "C++ Console Table and Graph/Plot Libraries"