FST  openfst-1.8.3
OpenFst Library
fstprune-main.cc
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2 //
3 // Licensed under the Apache License, Version 2.0 (the 'License');
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an 'AS IS' BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
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14 //
15 // See www.openfst.org for extensive documentation on this weighted
16 // finite-state transducer library.
17 //
18 // Prunes states and arcs of an FST w.r.t. the shortest path weight.
19 
20 #include <cstring>
21 #include <memory>
22 #include <string>
23 
24 #include <fst/flags.h>
25 #include <fst/script/fst-class.h>
26 #include <fst/script/prune.h>
28 
29 DECLARE_double(delta);
30 DECLARE_int64(nstate);
31 DECLARE_string(weight);
32 
33 int fstprune_main(int argc, char **argv) {
34  namespace s = fst::script;
37 
38  std::string usage = "Prunes states and arcs of an FST.\n\n Usage: ";
39  usage += argv[0];
40  usage += " [in.fst [out.fst]]\n";
41 
42  SET_FLAGS(usage.c_str(), &argc, &argv, true);
43  if (argc > 3) {
44  ShowUsage();
45  return 1;
46  }
47 
48  const std::string in_name =
49  (argc > 1 && strcmp(argv[1], "-") != 0) ? argv[1] : "";
50  const std::string out_name =
51  (argc > 2 && strcmp(argv[2], "-") != 0) ? argv[2] : "";
52 
53  std::unique_ptr<MutableFstClass> fst(MutableFstClass::Read(in_name, true));
54  if (!fst) return 1;
55 
56  const auto weight_threshold =
57  FST_FLAGS_weight.empty()
58  ? WeightClass::Zero(fst->WeightType())
59  : WeightClass(fst->WeightType(), FST_FLAGS_weight);
60 
61  s::Prune(fst.get(), weight_threshold, FST_FLAGS_nstate,
62  FST_FLAGS_delta);
63 
64  return !fst->Write(out_name);
65 }
void ShowUsage(bool long_usage=true)
Definition: flags.cc:138
int fstprune_main(int argc, char **argv)
#define SET_FLAGS(usage, argc, argv, rmflags)
Definition: flags.h:226
void Prune(MutableFst< Arc > *fst, const PruneOptions< Arc, ArcFilter > &opts=PruneOptions< Arc, ArcFilter >())
Definition: prune.h:114
DECLARE_int64(nstate)
DECLARE_double(delta)
DECLARE_string(weight)