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Why pure Go

go-ruby-matrix/matrix reimplements Ruby's matrix standard library in pure Go, with cgo disabled. Matrix/Vector arithmetic is deterministic and interpreter-independent: given its entries, the result is a pure function of those entries — no live binding, no evaluation of arbitrary Ruby. That is exactly the part that can — and should — live as a standalone Go library, separate from the interpreter.

A reusable library, bound by rbgo

This library is the deterministic core that backs Ruby's matrix in go-embedded-ruby. It is standalone and reusable so that:

  • any Go program can import github.com/go-ruby-matrix/matrix directly, with no Ruby runtime;
  • the dependency runs the other way — rbgo binds this module as a native module (the same pattern as go-ruby-regexp and go-ruby-erb), rather than this module depending on the interpreter;
  • the behaviour is pinned by a differential oracle against the system ruby -rmatrix, independent of any one consumer.

Exact where MRI is exact

Ruby's matrix carries Ruby's numeric tower: Integer and Rational entries stay exact, and a division only escapes to Float when the input is Float. This package mirrors that with a Num tower built on math/big — *big.Int for Integers, *big.Rat for Rationals, float64 for Floats — and reproduces MRI's inverse_from Gauss-Jordan elimination step for step (partial pivoting on the largest absolute pivot), so even a Float matrix's inverse reproduces MRI's exact rounding (e.g. -1.9999999999999998). An Integer matrix's determinant stays an Integer; inverse of an Integer matrix prints exact Rationals ((1/1), not 1). The arithmetic is a pure function of the entries — no interpreter required.

Why pure Go matters here

Because the library is CGO-free and dependency-free, it:

  • cross-compiles to every Go target with no C toolchain, and links into a single static binary;
  • has no dependency on the Ruby runtime — the dependency runs the other way;
  • can be differentially tested against ruby -rmatrix wherever a ruby is on PATH, while the cross-arch lanes (where ruby is absent) still validate the library itself.

See Usage & API for the surface and Roadmap for what is in scope.