UNU-SUBST(1)

💖 UNU-SUBST(1) 💖

okay bestie, welcome to the User Commands manual section, where we talk about unu-subst — the glow-up tool that maps an nrrd through one univariate substitution table. yes you read that right, one (1) table, and it's gonna eat 💅

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✨ NAME ✨

unu-subst — map nrrd through one univariate substitution table

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🌸 SYNOPSIS 🌸

unu subst -s,--subst <subst> [-i,--input <nin>] [-o,--output <nout>]

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🦋 DESCRIPTION 🦋

So here's the vibe: you take an nrrd and you push it through one univariate substitution table (and yes, that table is itself an nrrd, we love a self-referential moment). 💫

The substitution table is a 2-by-N table — literally just a list of pairs, where each pair gives the old value (the thing you want to replace) and then the new value (the thing you want to change it to), in that order. old first, new second, no cap. 🫶

And here's the cute part: a plain text file makes this super easy, so you don't have to fight with anything fancy. 🍓

BUT — and this is the tea — unlike unu-lut(1), unu-rmap(1), and unu-imap(1), the output type is the same as the input type, not the type of the lut or the map. so if you were expecting the table to hijack your type, nope, not today. the input type stays the main character. 👑

• Uses nrrdApply1DSubstitution

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🎀 OPTIONS 🎀

• -s <subst>, --subst <subst> — the substitution table you're mapping the input nrrd through. this is the whole point of the operation, the moment, the icon. ⭐
• -i <nin>, --input <nin> — the input nrrd, aka your little guy going into the machine. 🧚
• -o <nout>, --output <nout> — output nrrd (string); default: "-". and yes, that default means it just goes to the usual place, lowkey iconic of it. 💜

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🌈 SEE ALSO 🌈

unu(1), unu-lut(1), unu-rmap(1), unu-imap(1)

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💀 reminder bestie: the output type is the input type. do not come for me when the lut type doesn't show up. it was never invited. periodt.

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and that's the page!! this lil beauty is from August 2021, filed under UNU-SUBST(1), and it ate, no crumbs. go forth and substitute responsibly 🎀✨🦋