What it does
REDUCE is a computer algebra system for scalar, vector and matrix algebra, with high-precision approximation and programmable calculations.
REDUCE combines scalar, vector and matrix algebra with programmable calculations, numerical approximation and gnuplot graphics. Its native implementations differ: CSL supplies a graphical interface, while PSL is command-line based. The linked 2025 manual explains OUT redirection and SHUT: first output to an existing file, or reopening after SHUT, erases its prior contents; repeated use while still open appends. Turn off natural mathematical formatting when the output must be read back with IN. Experimental Web REDUCE runs a WebAssembly engine in the browser and emulates file commands through its menu. It is intended for simple experimentation, does not load user packages, and needs packages loaded in separate inputs. The mobile web build omits plotting, and web plotting keeps only the last plot. Source and distributions are free of charge.
Strengths
- Scalar, vector and matrix algebra
- Programmable calculations and arbitrary-precision approximation
Watch out for
- Graphical-interface availability depends on the implementation
Best for
- Symbolic mathematics with reusable calculation programs
Sources
- REDUCE Computer Algebra System (Oct 26, 2026)
- REDUCE2025 Output File Replacement and Readback (Oct 26, 2026)
- Experimental Web REDUCE Processing and File/Package/Plot Limits (Oct 26, 2026)