average_affine(1)

👑 average_affine(1) 💅

okay so bestie, welcome to average_affine — it's a tool from The Computational Morphology Toolkit (aka CMTK, iykyk) and it does exactly one thing but it does it so well. Buckle up 🎀

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✨ NAME ✨

average_affine — averages affine transformations. that's it. that's the whole vibe. 🦋

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🌸 SYNOPSIS 🌸

average_affine [options] x0 [x1 ...]
 WHERE x0 ... xN is [{-i,--inverse}] affine transformation #. (If the
first transformation in the sequence is inverted, then '--inverse' must
be preceded by '--', i.e., use '-- --inverse xform.path').

so like, x0 through xN are your affine transformations, and each one can be flipped with {-i,--inverse} if that's the energy you're bringing today. 💫

⚠️ bestie listen: if the first transformation in your sequence is inverted, then --inverse has to be preceded by --, so you literally type -- --inverse xform.path. yes really. it's giving "the parser needed a lil personal space". 😭

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💖 DESCRIPTION 💖

this tool computes the average of a sequence of user-provided affine coordinate transformations. you feed it a bunch of transforms, it hands you back the average one. no cap, that's the whole description. slay. ✨

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💅 OPTIONS 💅

🌈 Global Toolkit Options 🌈

(these are shared by all CMTK tools, so they'll feel familiar if you've been around the toolkit before 🫶)

• --help — writes the list of basic command line options to standard output. the lil starter pack. 🍓
• --help-all — writes the complete list of basic and advanced command line options to standard output. the deluxe edition, the full lore, the director's cut. 👑
• --wiki — writes the list of command line options to standard output in MediaWiki markup. for when you're documenting, bestie. 📝
• --man — writes man page source in 'nroff' markup to standard output. 🧚
• --version — writes toolkit version to standard output. 🏷️
• --echo — writes the current command line to standard output. so you can see exactly what you typed, no revisionist history. 😌
• --verbose-level <integer> — set verbosity level. crank it up, turn the volume on. 🔊
• --verbose, -v — increment verbosity level by 1. ⚠️ deprecated — supported for backward compatibility only. it's giving legacy, but we still love her. 💀
• --threads <integer> — set maximum number of parallel threads (for POSIX threads and OpenMP). multitasking queen behavior. 🔥

🎀 Main Options 🎀

• --include-reference, -r — include reference coordinate system in the averaging. let the reference girl join the group chat. 💜
• --outfile <string>, -o <string> — output transformation. [Default: average.xform ] — note the default literally has a space before the closing bracket, that's just how she is, iconic. 💅
• --append, -a — append to output file [default: overwrite]. the default is to overwrite, so if you wanna keep what's already there you gotta say -a, bestie. 🙈
• --invert-output, -I — invert averaged transformation before output [default: no]. flip it, turn it, reverse it. 🔄

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🫶 AUTHORS 🫶

Torsten Rohlfing, with contributions from Michael P. Hasak, Greg Jefferis, Calvin R. Maurer, Daniel B. Russakoff, and Yaroslav Halchenko. the whole squad, the founding mothers and fathers of this codebase, we stan. 💖

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📜 LICENSE 📜

http://www.fsf.org/licensing/licenses/gpl.html

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💀 BUGS 💀

report bugs at http://nitrc.org/projects/cmtk/

not me asking you to file an issue — okay yes, me asking you to file an issue. please. 🥺

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⭐ ACKNOWLEDGMENTS ⭐

CMTK is developed with support from the NIAAA under Grant AA021697, National Consortium on Alcohol and Neurodevelopment in Adolescence (N-CANDA): Data Integration Component. From April 2009 through September 2011, CMTK development and maintenance was supported by the NIBIB under Grant EB008381.

the funding grandparents came THROUGH, we owe them everything honestly. 🌸

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and that's the whole page, bestie!! this was CMTK 3.3.1p2, dated Jun 24 2026, and yes it's the average_affine(1) manual page — you were literally reading it the whole time. go average something. slay. 💅✨👑