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diff --git a/kaldi_io/src/tools/openfst/include/fst/push.h b/kaldi_io/src/tools/openfst/include/fst/push.h
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-// push.h
-
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-//
-// Copyright 2005-2010 Google, Inc.
-// Author: allauzen@google.com (Cyril Allauzen)
-//
-// \file
-// Class to reweight/push an FST.
-
-#ifndef FST_LIB_PUSH_H__
-#define FST_LIB_PUSH_H__
-
-#include <vector>
-using std::vector;
-
-#include <fst/factor-weight.h>
-#include <fst/fst.h>
-#include <fst/arc-map.h>
-#include <fst/reweight.h>
-#include <fst/shortest-distance.h>
-
-
-namespace fst {
-
-// Private helper functions for Push
-namespace internal {
-
-// Compute the total weight (sum of the weights of all accepting paths) from
-// the output of ShortestDistance. 'distance' is the shortest distance from the
-// initial state when 'reverse == false' and to the final states when
-// 'reverse == true'.
-template <class Arc>
-typename Arc::Weight ComputeTotalWeight(
- const Fst<Arc> &fst,
- const vector<typename Arc::Weight> &distance,
- bool reverse) {
- if (reverse)
- return fst.Start() < distance.size() ?
- distance[fst.Start()] : Arc::Weight::Zero();
-
- typename Arc::Weight sum = Arc::Weight::Zero();
- for (typename Arc::StateId s = 0; s < distance.size(); ++s)
- sum = Plus(sum, Times(distance[s], fst.Final(s)));
- return sum;
-}
-
-// Divide the weight of every accepting path by 'w'. The weight 'w' is
-// divided at the final states if 'at_final == true' and at the
-// initial state otherwise.
-template <class Arc>
-void RemoveWeight(MutableFst<Arc> *fst, typename Arc::Weight w, bool at_final) {
- if ((w == Arc::Weight::One()) || (w == Arc::Weight::Zero()))
- return;
-
- if (at_final) {
- // Remove 'w' from the final states
- for (StateIterator< MutableFst<Arc> > sit(*fst);
- !sit.Done();
- sit.Next())
- fst->SetFinal(sit.Value(),
- Divide(fst->Final(sit.Value()), w, DIVIDE_RIGHT));
- } else { // at_final == false
- // Remove 'w' from the initial state
- typename Arc::StateId start = fst->Start();
- for (MutableArcIterator<MutableFst<Arc> > ait(fst, start);
- !ait.Done();
- ait.Next()) {
- Arc arc = ait.Value();
- arc.weight = Divide(arc.weight, w, DIVIDE_LEFT);
- ait.SetValue(arc);
- }
- fst->SetFinal(start, Divide(fst->Final(start), w, DIVIDE_LEFT));
- }
-}
-} // namespace internal
-
-// Pushes the weights in FST in the direction defined by TYPE. If
-// pushing towards the initial state, the sum of the weight of the
-// outgoing transitions and final weight at a non-initial state is
-// equal to One() in the resulting machine. If pushing towards the
-// final state, the same property holds on the reverse machine.
-//
-// Weight needs to be left distributive when pushing towards the
-// initial state and right distributive when pushing towards the final
-// states.
-template <class Arc>
-void Push(MutableFst<Arc> *fst,
- ReweightType type,
- float delta = kDelta,
- bool remove_total_weight = false) {
- vector<typename Arc::Weight> distance;
- ShortestDistance(*fst, &distance, type == REWEIGHT_TO_INITIAL, delta);
- typename Arc::Weight total_weight = Arc::Weight::One();
- if (remove_total_weight)
- total_weight = internal::ComputeTotalWeight(*fst, distance,
- type == REWEIGHT_TO_INITIAL);
- Reweight(fst, distance, type);
- if (remove_total_weight)
- internal::RemoveWeight(fst, total_weight, type == REWEIGHT_TO_FINAL);
-}
-
-const uint32 kPushWeights = 0x0001;
-const uint32 kPushLabels = 0x0002;
-const uint32 kPushRemoveTotalWeight = 0x0004;
-const uint32 kPushRemoveCommonAffix = 0x0008;
-
-// OFST obtained from IFST by pushing weights and/or labels according
-// to PTYPE in the direction defined by RTYPE. Weight needs to be
-// left distributive when pushing weights towards the initial state
-// and right distributive when pushing weights towards the final
-// states.
-template <class Arc, ReweightType rtype>
-void Push(const Fst<Arc> &ifst,
- MutableFst<Arc> *ofst,
- uint32 ptype,
- float delta = kDelta) {
-
- if ((ptype & (kPushWeights | kPushLabels)) == kPushWeights) {
- *ofst = ifst;
- Push(ofst, rtype, delta, ptype & kPushRemoveTotalWeight);
- } else if (ptype & kPushLabels) {
- const StringType stype = rtype == REWEIGHT_TO_INITIAL
- ? STRING_LEFT
- : STRING_RIGHT;
- vector<typename GallicArc<Arc, stype>::Weight> gdistance;
- VectorFst<GallicArc<Arc, stype> > gfst;
- ArcMap(ifst, &gfst, ToGallicMapper<Arc, stype>());
- if (ptype & kPushWeights ) {
- ShortestDistance(gfst, &gdistance, rtype == REWEIGHT_TO_INITIAL, delta);
- } else {
- ArcMapFst<Arc, Arc, RmWeightMapper<Arc> >
- uwfst(ifst, RmWeightMapper<Arc>());
- ArcMapFst<Arc, GallicArc<Arc, stype>, ToGallicMapper<Arc, stype> >
- guwfst(uwfst, ToGallicMapper<Arc, stype>());
- ShortestDistance(guwfst, &gdistance, rtype == REWEIGHT_TO_INITIAL, delta);
- }
- typename GallicArc<Arc, stype>::Weight total_weight =
- GallicArc<Arc, stype>::Weight::One();
- if (ptype & (kPushRemoveTotalWeight | kPushRemoveCommonAffix)) {
- total_weight = internal::ComputeTotalWeight(
- gfst, gdistance, rtype == REWEIGHT_TO_INITIAL);
- total_weight = typename GallicArc<Arc, stype>::Weight(
- ptype & kPushRemoveCommonAffix ? total_weight.Value1()
- : StringWeight<typename Arc::Label, stype>::One(),
- ptype & kPushRemoveTotalWeight ? total_weight.Value2()
- : Arc::Weight::One());
- }
- Reweight(&gfst, gdistance, rtype);
- if (ptype & (kPushRemoveTotalWeight | kPushRemoveCommonAffix))
- internal::RemoveWeight(&gfst, total_weight, rtype == REWEIGHT_TO_FINAL);
- FactorWeightFst< GallicArc<Arc, stype>, GallicFactor<typename Arc::Label,
- typename Arc::Weight, stype> > fwfst(gfst);
- ArcMap(fwfst, ofst, FromGallicMapper<Arc, stype>());
- ofst->SetOutputSymbols(ifst.OutputSymbols());
- } else {
- LOG(WARNING) << "Push: pushing type is set to 0: "
- << "pushing neither labels nor weights.";
- *ofst = ifst;
- }
-}
-
-} // namespace fst
-
-#endif /* FST_LIB_PUSH_H_ */
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