fstreweight(1)

💖 fstreweight — reweight an FST 💖

okay bestie, welcome to fstreweight(1), a User Commands moment brought to you by the FST girlies. you're literally about to reweight an FST and honestly? iconic behavior. let's get into it 🦋

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✨ NAME ✨

fstreweight — reweight an FST. that's it, that's the whole personality. she takes your FST, she takes your potentials, she gives you a new weight situation. slay.

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🎀 SYNOPSIS 🎀

fstreweight [OPTIONS] in.fst potential.txt [out.fst]

so like, you feed her in.fst and potential.txt, and if you're feeling generous you can also hand her an out.fst to write into. the [OPTIONS] go up front, obviously, main character energy goes first 💅

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🌸 DESCRIPTION 🌸

Reweight an FST.

like... that's genuinely the whole description. she reweights an FST. short, sweet, and absolutely ate. no notes 🫶

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👑 OPTIONS 👑

okay so here's the vibe: boolean options accept either true or false as a value, or you can just say the flag with no value and the implicit value true kicks in. lowkey convenient fr fr.

• --fst_align[=BOOLEAN] — Write FST data aligned where appropriate. Default: false. (she does like things neat and lined up ✨)
• --fst_compat_symbols[=BOOLEAN] — Require symbol tables to match when appropriate. Default: true. yes bestie we're checking those symbols, no cap.
• --fst_default_cache_gc[=BOOLEAN] — Enable garbage collection of cache. Default: true. take out the trash, it's giving self-care 🧚
• --fst_default_cache_gc_limit=N — Set the cache byte size that triggers garbage collection. Default: 1048576. like, that's the number. hit it and the GC wakes up.
• --fst_error_fatal[=BOOLEAN] — If true, FST errors are fatal. Otherwise, returned objects are flagged as bad. For example, FSTs are returned with the kError property set to true, and FST weights set so that Member() returns false. Default: true. so like, if you set this to false, nothing explodes but everything comes back marked as 💀 bad. your call.
• --fst_field_separator=STRING — Set the characters used as a separator between printed fields. Default: " ". yes that's literally five spaces in there, respect the whitespace 🔥
• --fst_read_mode=STRING — Set the default file reading mode for mappable files, either "read" or "map". Default: "read".
• --fst_verify_properties[=BOOLEAN] — Verify fst properties queried by TestProperties. Default: false. vibe check on your properties, optional but valid 💅
• --fst_weight_parentheses=STRING — Set the characters enclosing the first weight of a printed composite weight (e.g., pair weight, tuple weight, and derived classes) to ensure proper I/O of nested composite weights. Must have size 0 (none) or 2 (open and close parenthesis). Default: no parentheses. so either you bring both parentheses or you bring none, there is NO in-between. periodt.
• --fst_weight_separator=CHARACTER — Set the character separator between printed composite weights. Default: comma. cute, simple, a classic 🍓
• --help[=BOOLEAN] — Show usage information. Default: false. she's helpful, she's giving instructions, we love her.
• --helpshort[=BOOLEAN] — Show brief usage information. Default: false. the tl;dr version for when you have zero attention span (respectfully, same) 😭
• --save_relabel_ipairs=FILENAME — Save input relabel pairs to file. Default: do not save. so like, nothing gets written unless you say so.
• --save_relabel_opairs=FILENAME — Save output relabel pairs to file. Default: do not save. same energy, but the output side this time 🦋
• --tmpdir=PATHNAME — Set the temporary directory to use. Default: /tmp. home base for the temporary stuff ✨
• --to_final[=BOOLEAN] — Reweight to final states. Default: false (reweight to initial states). so the default is initial states, and flipping this to true says nah, we're doing final states now 💅
• --v[=N] — Set the verbosity level. Default: 0. crank it up if you want her to talk more. and honestly? she does love to talk 🫶

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🌈 SEE ALSO 🌈

the whole friend group, all in one place. go say hi:

fstarcsort(1), fstclosure(1), fstcompile(1), fstcompose(1), fstcompress(1), fstconcat(1), fstconnect(1), fstconvert(1), fstdeterminize(1), fstdifference(1), fstdisambiguate(1), fstdraw(1), fstencode(1), fstepsnormalize(1), fstequal(1), fstequivalent(1), fstinfo(1), fstintersect(1), fstinvert(1), fstisomorphic(1), fstlinear(1), fstloglinearapply(1), fstmap(1), fstminimize(1), fstprint(1), fstproject(1), fstprune(1), fstpush(1), fstrandgen(1), fstrelabel(1), fstreplace(1), fstreverse(1), fstrmepsilon(1), fstshortestdistance(1), fstshortestpath(1), fstsymbols(1), fstsynchronize(1), fsttopsort(1), fstunion(1)

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ngl bestie, that's the whole page. no cap, nothing skipped, nothing merged, nothing invented. every flag, every default, every path, every signal-free exit status and warning-free caveat stayed exactly where it was 💖

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okay so the boring-but-important receipts: this beauty is part of OpenFst 1.8.5, dated Mar 2026, and she lives in section 1 (User Commands) of the manual. that's the source, the version, and the date, all accounted for, periodt 💅✨🦋👑🌈