numdiff を Homebrew でインストール

プロジェクトリンク

• ホームページ

コマンドとエイリアス

• ndselect
• numdiff

プロジェクトの歴史

The official manual for Numdiff 5.9 carries copyrights from 2005 through 2017 and documents a mature Unix-style C program built with the usual `configure`, `make`, and `make install` workflow. The 5.9 manual also notes that older 5.x releases accepted fewer options and that 4.0.0 and 3.x used a different output format, so the package has a real pre-5.x history even though public narrative sources are sparse.

採用の歴史

Numdiff has modest adoption: it is packaged by Homebrew, Debian/Ubuntu, MacPorts, Nix, and GNU Guix, but it is not a broad ecosystem cornerstone. Homebrew's formula page listed only 43 installs over 365 days on July 1, 2026, which fits the profile of a specialist testing/scientific utility that users reach for when normal diffs are too literal.

使われ方

The practical workflow is comparing generated numeric output line by line and field by field while setting absolute or relative tolerances and accepting equivalent numeric notation. Numdiff also ships `ndselect` for selecting lines and fields, and version 5.9 added a raw output format intended for machine parsing.

パッケージ好きにとっての重要性

Numdiff is the classic package-manager long tail: tiny, stable, GPL-licensed, and exactly useful when validating numerical programs whose outputs vary by rounding, notation, platform, compiler, or BLAS implementation. It is most likely to appear in regression-test scripts, scientific-code QA, and packaging test fixtures.

タイムライン

• 2005-2017: Years covered by the official manual copyright range.
• 5.9: Adds compact raw output intended for parsing by other programs.

Related projects

• GNU diffutils
• wdiff
• cmp

ソース

• https://formulae.brew.sh/formula/numdiff
• https://packages.guix.gnu.org/packages/numdiff/5.9.0/
• https://www.nongnu.org/numdiff/
• https://www.nongnu.org/numdiff/numdiff.html