diff options
Diffstat (limited to 'src/include/fst/script/shortest-path.h')
| -rw-r--r-- | src/include/fst/script/shortest-path.h | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/src/include/fst/script/shortest-path.h b/src/include/fst/script/shortest-path.h new file mode 100644 index 0000000..b3a3eb9 --- /dev/null +++ b/src/include/fst/script/shortest-path.h @@ -0,0 +1,190 @@ + +// 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: jpr@google.com (Jake Ratkiewicz) + +#ifndef FST_SCRIPT_SHORTEST_PATH_H_ +#define FST_SCRIPT_SHORTEST_PATH_H_ + +#include <vector> +using std::vector; + +#include <fst/script/arg-packs.h> +#include <fst/script/fst-class.h> +#include <fst/script/weight-class.h> +#include <fst/shortest-path.h> +#include <fst/script/shortest-distance.h> // for ShortestDistanceOptions + +namespace fst { +namespace script { + +struct ShortestPathOptions + : public fst::script::ShortestDistanceOptions { + const size_t nshortest; + const bool unique; + const bool has_distance; + const bool first_path; + const WeightClass weight_threshold; + const int64 state_threshold; + + ShortestPathOptions(QueueType qt, size_t n = 1, + bool u = false, bool hasdist = false, + float d = fst::kDelta, bool fp = false, + WeightClass w = fst::script::WeightClass::Zero(), + int64 s = fst::kNoStateId) + : ShortestDistanceOptions(qt, ANY_ARC_FILTER, kNoStateId, d), + nshortest(n), unique(u), has_distance(hasdist), first_path(fp), + weight_threshold(w), state_threshold(s) { } +}; + +typedef args::Package<const FstClass &, MutableFstClass *, + vector<WeightClass> *, const ShortestPathOptions &> + ShortestPathArgs1; + + +template<class Arc> +void ShortestPath(ShortestPathArgs1 *args) { + const Fst<Arc> &ifst = *(args->arg1.GetFst<Arc>()); + MutableFst<Arc> *ofst = args->arg2->GetMutableFst<Arc>(); + const ShortestPathOptions &opts = args->arg4; + typedef typename Arc::StateId StateId; + typedef typename Arc::Weight Weight; + typedef AnyArcFilter<Arc> ArcFilter; + + vector<typename Arc::Weight> weights; + typename Arc::Weight weight_threshold = + *(opts.weight_threshold.GetWeight<Weight>()); + + switch (opts.queue_type) { + case AUTO_QUEUE: { + typedef AutoQueue<StateId> Queue; + Queue *queue = QueueConstructor<Queue, Arc, + ArcFilter>::Construct(ifst, &weights); + fst::ShortestPathOptions<Arc, Queue, ArcFilter> spopts( + queue, ArcFilter(), opts.nshortest, opts.unique, + opts.has_distance, opts.delta, opts.first_path, + weight_threshold, opts.state_threshold); + ShortestPath(ifst, ofst, &weights, spopts); + delete queue; + return; + } + case FIFO_QUEUE: { + typedef FifoQueue<StateId> Queue; + Queue *queue = QueueConstructor<Queue, Arc, + ArcFilter>::Construct(ifst, &weights); + fst::ShortestPathOptions<Arc, Queue, ArcFilter> spopts( + queue, ArcFilter(), opts.nshortest, opts.unique, + opts.has_distance, opts.delta, opts.first_path, + weight_threshold, opts.state_threshold); + ShortestPath(ifst, ofst, &weights, spopts); + delete queue; + return; + } + case LIFO_QUEUE: { + typedef LifoQueue<StateId> Queue; + Queue *queue = QueueConstructor<Queue, Arc, + ArcFilter >::Construct(ifst, &weights); + fst::ShortestPathOptions<Arc, Queue, ArcFilter> spopts( + queue, ArcFilter(), opts.nshortest, opts.unique, + opts.has_distance, opts.delta, opts.first_path, + weight_threshold, opts.state_threshold); + ShortestPath(ifst, ofst, &weights, spopts); + delete queue; + return; + } + case SHORTEST_FIRST_QUEUE: { + typedef NaturalShortestFirstQueue<StateId, Weight> Queue; + Queue *queue = QueueConstructor<Queue, Arc, + ArcFilter>::Construct(ifst, &weights); + fst::ShortestPathOptions<Arc, Queue, ArcFilter> spopts( + queue, ArcFilter(), opts.nshortest, opts.unique, + opts.has_distance, opts.delta, opts.first_path, + weight_threshold, opts.state_threshold); + ShortestPath(ifst, ofst, &weights, spopts); + delete queue; + return; + } + case STATE_ORDER_QUEUE: { + typedef StateOrderQueue<StateId> Queue; + Queue *queue = QueueConstructor<Queue, Arc, + ArcFilter>::Construct(ifst, &weights); + fst::ShortestPathOptions<Arc, Queue, ArcFilter> spopts( + queue, ArcFilter(), opts.nshortest, opts.unique, + opts.has_distance, opts.delta, opts.first_path, + weight_threshold, opts.state_threshold); + ShortestPath(ifst, ofst, &weights, spopts); + delete queue; + return; + } + case TOP_ORDER_QUEUE: { + typedef TopOrderQueue<StateId> Queue; + Queue *queue = QueueConstructor<Queue, Arc, + ArcFilter>::Construct(ifst, &weights); + fst::ShortestPathOptions<Arc, Queue, ArcFilter> spopts( + queue, ArcFilter(), opts.nshortest, opts.unique, + opts.has_distance, opts.delta, opts.first_path, + weight_threshold, opts.state_threshold); + ShortestPath(ifst, ofst, &weights, spopts); + delete queue; + return; + } + default: + FSTERROR() << "Unknown queue type: " << opts.queue_type; + ofst->SetProperties(kError, kError); + } + + // Copy the weights back + args->arg3->resize(weights.size()); + for (unsigned i = 0; i < weights.size(); ++i) { + (*args->arg3)[i] = WeightClass(weights[i]); + } +} + +// 2 +typedef args::Package<const FstClass &, MutableFstClass *, + size_t, bool, bool, WeightClass, + int64> ShortestPathArgs2; + +template<class Arc> +void ShortestPath(ShortestPathArgs2 *args) { + const Fst<Arc> &ifst = *(args->arg1.GetFst<Arc>()); + MutableFst<Arc> *ofst = args->arg2->GetMutableFst<Arc>(); + typename Arc::Weight weight_threshold = + *(args->arg6.GetWeight<typename Arc::Weight>()); + + ShortestPath(ifst, ofst, args->arg3, args->arg4, args->arg5, + weight_threshold, args->arg7); +} + + +// 1 +void ShortestPath(const FstClass &ifst, MutableFstClass *ofst, + vector<WeightClass> *distance, + const ShortestPathOptions &opts); + + +// 2 +void ShortestPath(const FstClass &ifst, MutableFstClass *ofst, + size_t n = 1, bool unique = false, + bool first_path = false, + WeightClass weight_threshold = + fst::script::WeightClass::Zero(), + int64 state_threshold = fst::kNoStateId); + +} // namespace script +} // namespace fst + + + +#endif // FST_SCRIPT_SHORTEST_PATH_H_ |