From 2c793f19a4310037bbc362aaf8f43da2e998f385 Mon Sep 17 00:00:00 2001
From: Vassil Panayotov <vd.panayotov@gmail.com>
Date: Sat, 29 Apr 2017 10:16:24 +0300
Subject: [PATCH] [src] Remove the GetLinearSymbolSequences() function

This function is not currently needed, and the implementation was buggy
---
 src/fstext/fstext-utils-inl.h   | 70 ---------------------------------
 src/fstext/fstext-utils-test.cc | 10 -----
 src/fstext/fstext-utils.h       | 21 ----------
 3 files changed, 101 deletions(-)

diff --git a/src/fstext/fstext-utils-inl.h b/src/fstext/fstext-utils-inl.h
index f3b0b68b502..b28dd2b698f 100644
--- a/src/fstext/fstext-utils-inl.h
+++ b/src/fstext/fstext-utils-inl.h
@@ -215,76 +215,6 @@ bool GetLinearSymbolSequence(const Fst<Arc> &fst,
   }
 }
 
-// see fstext-utils.h for comment.
-template<class Arc, class I>
-bool GetLinearSymbolSequences(const Fst<Arc> &fst,
-                              vector<vector<I> > *isymbols_out,
-                              vector<vector<I> > *osymbols_out,
-                              vector<typename Arc::Weight> *weights_out) {
-  typedef typename Arc::StateId StateId;
-  typedef typename Arc::Weight Weight;
-
-  if (isymbols_out) isymbols_out->clear();
-  if (osymbols_out) osymbols_out->clear();
-  if (weights_out) weights_out->clear();
-
-  StateId start_state = fst.Start();
-  if (start_state == kNoStateId) {  // no paths.
-    return true; // empty FST counts as having this structure.
-  }
-
-  if (fst.Final(start_state) != Weight::Zero())
-    return false; // We don't allow final-prob on the start state.
-
-  size_t N = fst.NumArcs(start_state), n = 0;
-  if (isymbols_out) isymbols_out->resize(N);
-  if (osymbols_out) osymbols_out->resize(N);
-  if (weights_out) weights_out->resize(N);
-
-  bool error = false;
-
-  for (ArcIterator<Fst<Arc> > aiter(fst, start_state);
-       !aiter.Done();
-       aiter.Next(), n++) {
-    StateId cur_state = start_state;
-    if (isymbols_out) (*isymbols_out)[n].clear();
-    if (osymbols_out) (*osymbols_out)[n].clear();
-    if (weights_out) (*weights_out)[n] = Weight::One();
-
-    while (1) {
-      if (fst.Final(cur_state) != Weight::Zero()) {
-        (*weights_out)[n] = Times((*weights_out)[n],
-                                  fst.Final(cur_state));
-        if (fst.NumArcs(cur_state) != 0)
-          error = true;
-        break;
-      } else {
-        if (fst.NumArcs(cur_state) != 1) {
-          error = true;
-          break;
-        }
-        ArcIterator<Fst<Arc> > aiter(fst, cur_state);
-        const Arc &arc = aiter.Value();
-        if (isymbols_out && arc.ilabel != 0)
-          (*isymbols_out)[n].push_back(arc.ilabel);
-        if (osymbols_out && arc.ilabel != 0)
-          (*osymbols_out)[n].push_back(arc.olabel);
-        if (weights_out)
-          (*weights_out)[n] = Times((*weights_out)[n], arc.weight);
-        cur_state = arc.nextstate;
-      }
-    }
-    if (error) break;
-  }
-  if (error) {
-    if (isymbols_out) isymbols_out->clear();
-    if (osymbols_out) osymbols_out->clear();
-    if (weights_out) weights_out->clear();
-    return false;
-  } else {
-    return true;
-  }
-}
 
 // see fstext-utils.sh for comment.
 template<class Arc>
diff --git a/src/fstext/fstext-utils-test.cc b/src/fstext/fstext-utils-test.cc
index b016b53691f..96ccf67366e 100644
--- a/src/fstext/fstext-utils-test.cc
+++ b/src/fstext/fstext-utils-test.cc
@@ -53,16 +53,6 @@ void TestMakeLinearAcceptor() {
 
   if (vec2.size() != 0 || vec3.size() != 0) { // This test might not work
     // for empty sequences...
-    {
-      vector<vector<I> > vecs2;
-      vector<vector<I> > vecs3;
-      vector<Weight> ws;
-      GetLinearSymbolSequences(vfst, &vecs2, &vecs3, &ws);
-      assert(vecs2.size() == 1);
-      assert(vecs2[0] == vec2);
-      assert(vecs3[0] == vec3);
-      assert(ApproxEqual(ws[0], w));
-    }
     {
       vector<VectorFst<Arc> > fstvec;
       NbestAsFsts(vfst, 1, &fstvec);
diff --git a/src/fstext/fstext-utils.h b/src/fstext/fstext-utils.h
index a9038858eda..5caf4f58cb4 100644
--- a/src/fstext/fstext-utils.h
+++ b/src/fstext/fstext-utils.h
@@ -135,27 +135,6 @@ bool GetLinearSymbolSequence(const Fst<Arc> &fst,
                              vector<I> *osymbols_out,
                              typename Arc::Weight *tot_weight_out);
 
-/// GetLinearSymbolSequence gets the symbol sequences and weights
-/// from an FST as output by the ShortestPath algorithm (called with
-/// some parameter n), which has up to n arcs out from the start state,
-/// and if you follow one of the arcs you enter a linear sequence of
-/// states.  This function outputs the info in a more N-best-list-like
-/// format.  It returns true if the FST had the expected structure,
-/// and false otherwise (note: an empty FST counts as having this
-/// structure).  We don't accept an FST that has a final-prob on the start
-/// state, as it wouldn't be clear whether to put it as the first or
-/// last path (this function is used in an N-best context where the
-/// paths' ordering is somewhat meaningful.)
-/// This function will set the output vectors to the appropriate
-/// size, and for each path will output the input and output symbols as
-/// vectors (not including epsilons).  It outputs the total weight
-/// for each path.
-template<class Arc, class I>
-bool GetLinearSymbolSequences(const Fst<Arc> &fst,
-                              vector<vector<I> > *isymbols_out,
-                              vector<vector<I> > *osymbols_out,
-                              vector<typename Arc::Weight> *tot_weight_out);
-
 
 /// This function converts an FST with a special structure, which is
 /// output by the OpenFst functions ShortestPath and RandGen, and converts