eqn
Equation preprocessor for the groff (GNU Troff) document formatting system.
See also troff and groff.
More information: https://manned.org/eqn.
- Process input with equations, saving the output for future typesetting with groff to PostScript:
eqn path/to/input.eqn > path/to/output.roff
- Typeset an input file with equations to PDF using the [me] macro package:
eqn -T pdf path/to/input.eqn | groff -me -T pdf > path/to/output.pdf