plotutils

It is used in projects such as PSPP and UMLgraph, and in many areas of academic research,[1][2][3] and is included in many Linux distributions such as Debian.

Its stand-alone command-line tools can generate graphs and perform numerical calculation of spline curves and systems of ordinary differential equations.

Plotutils is a GNU package and is distributed under a free software licence, the GPL.

A graph utility and various plot filters were present in the first releases of Unix from Bell Laboratories.

In 1995, the package was significantly expanded by writing a device-independent, standalone version of libplot, and by rewriting graph from scratch, turning it into a real-time filter.