fstprune(1)

💅 fstprune — the girlies are pruning

okay bestie, welcome to fstprune, part of the OpenFst family of User Commands. She's a little tool that does one job and does it iconically: she prunes states and arcs of an FST. That's it. That's the whole vibe. 🦋

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🌸 NAME 🌸

fstprune — prune states and arcs of an FST

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✨ SYNOPSIS ✨

fstprune [OPTIONS] [in.fst [out.fst]]

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🎀 DESCRIPTION 🎀

Prunes states and arcs of an FST.

Periodt. That's literally the whole description. No cap. 🔥

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👑 OPTIONS 👑

so first things first, bestie: boolean options are chill like that — they accept either true or false as a value, OR you can just... not give a value at all, and they'll implicitly be true. Lowkey generous of them. 💖

• --delta=VALUE — Set the comparison/quantization delta. Default: 0.000976562.
• --fst_align[=BOOLEAN] — Write FST data aligned where appropriate. Default: false.
• --fst_compat_symbols[=BOOLEAN] — Require symbol tables to match when appropriate. Default: true.
• --fst_default_cache_gc[=BOOLEAN] — Enable garbage collection of cache. Default: true.
• --fst_default_cache_gc_limit=N — Set the cache byte size that triggers garbage collection. Default: 1048576.
• --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.
• --fst_field_separator=STRING — Set the characters used as a separator between printed fields. Default: " ".
• --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.
• --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.
• --fst_weight_separator=CHARACTER — Set the character separator between printed composite weights. Default: comma.
• --help[=BOOLEAN] — Show usage information. Default: false.
• --helpshort[=BOOLEAN] — Show brief usage information. Default: false.
• --nstate=NUMBER — Set the state number threshold. Default: -1.
• --save_relabel_ipairs=FILENAME — Save input relabel pairs to file. Default: do not save.
• --save_relabel_opairs=FILENAME — Save output relabel pairs to file. Default: do not save.
• --tmpdir=PATHNAME — Set the temporary directory to use. Default: /tmp.
• --v[=N] — Set the verbosity level. Default: 0.
• --weight=THRESHOLD — Set the weight threshold. Default: "".

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🌈 SEE ALSO 🌈

the whole friend group 💜 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), fstpush(1), fstrandgen(1), fstrelabel(1), fstreplace(1), fstreverse(1), fstreweight(1), fstrmepsilon(1), fstshortestdistance(1), fstshortestpath(1), fstsymbols(1), fstsynchronize(1), fsttopsort(1), fstunion(1)

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that's the whole page babes 🫶 this one's brought to you by OpenFst 1.8.5, dated Mar 2026. go prune something cute, mwah 💋✨