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Diffstat (limited to 'kaldi_io/src/tools/openfst/include/fst/sparse-power-weight.h')
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1 files changed, 225 insertions, 0 deletions
diff --git a/kaldi_io/src/tools/openfst/include/fst/sparse-power-weight.h b/kaldi_io/src/tools/openfst/include/fst/sparse-power-weight.h new file mode 100644 index 0000000..a1ff56a --- /dev/null +++ b/kaldi_io/src/tools/openfst/include/fst/sparse-power-weight.h @@ -0,0 +1,225 @@ +// sparse-power-weight.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: [email protected] (Kasturi Rangan Raghavan) +// Inspiration: [email protected] (Cyril Allauzen) +// +// \file +// Cartesian power weight semiring operation definitions. +// Uses SparseTupleWeight as underlying representation. + +#ifndef FST_LIB_SPARSE_POWER_WEIGHT_H__ +#define FST_LIB_SPARSE_POWER_WEIGHT_H__ + +#include<string> + +#include <fst/sparse-tuple-weight.h> +#include <fst/weight.h> + + +namespace fst { + +// Below SparseTupleWeight*Mapper are used in conjunction with +// SparseTupleWeightMap to compute the respective semiring operations +template<class W, class K> +struct SparseTupleWeightPlusMapper { + W Map(const K& k, const W& v1, const W& v2) const { + return Plus(v1, v2); + } +}; + +template<class W, class K> +struct SparseTupleWeightTimesMapper { + W Map(const K& k, const W& v1, const W& v2) const { + return Times(v1, v2); + } +}; + +template<class W, class K> +struct SparseTupleWeightDivideMapper { + SparseTupleWeightDivideMapper(DivideType divide_type) { + divide_type_ = divide_type; + } + W Map(const K& k, const W& v1, const W& v2) const { + return Divide(v1, v2, divide_type_); + } + DivideType divide_type_; +}; + +template<class W, class K> +struct SparseTupleWeightApproxMapper { + SparseTupleWeightApproxMapper(float delta) { delta_ = delta; } + W Map(const K& k, const W& v1, const W& v2) const { + return ApproxEqual(v1, v2, delta_) ? W::One() : W::Zero(); + } + float delta_; +}; + +// Sparse cartesian power semiring: W ^ n +// Forms: +// - a left semimodule when W is a left semiring, +// - a right semimodule when W is a right semiring, +// - a bisemimodule when W is a semiring, +// the free semimodule of rank n over W +// The Times operation is overloaded to provide the +// left and right scalar products. +// K is the key value type. kNoKey(-1) is reserved for internal use +template <class W, class K = int> +class SparsePowerWeight : public SparseTupleWeight<W, K> { + public: + using SparseTupleWeight<W, K>::Zero; + using SparseTupleWeight<W, K>::One; + using SparseTupleWeight<W, K>::NoWeight; + using SparseTupleWeight<W, K>::Quantize; + using SparseTupleWeight<W, K>::Reverse; + + typedef SparsePowerWeight<typename W::ReverseWeight, K> ReverseWeight; + + SparsePowerWeight() {} + + SparsePowerWeight(const SparseTupleWeight<W, K> &w) : + SparseTupleWeight<W, K>(w) { } + + template <class Iterator> + SparsePowerWeight(Iterator begin, Iterator end) : + SparseTupleWeight<W, K>(begin, end) { } + + SparsePowerWeight(const K &key, const W &w) : + SparseTupleWeight<W, K>(key, w) { } + + static const SparsePowerWeight<W, K> &Zero() { + static const SparsePowerWeight<W, K> zero(SparseTupleWeight<W, K>::Zero()); + return zero; + } + + static const SparsePowerWeight<W, K> &One() { + static const SparsePowerWeight<W, K> one(SparseTupleWeight<W, K>::One()); + return one; + } + + static const SparsePowerWeight<W, K> &NoWeight() { + static const SparsePowerWeight<W, K> no_weight( + SparseTupleWeight<W, K>::NoWeight()); + return no_weight; + } + + // Overide this: Overwrite the Type method to reflect the key type + // if using non-default key type. + static const string &Type() { + static string type; + if(type.empty()) { + type = W::Type() + "_^n"; + if(sizeof(K) != sizeof(uint32)) { + string size; + Int64ToStr(8 * sizeof(K), &size); + type += "_" + size; + } + } + return type; + } + + static uint64 Properties() { + uint64 props = W::Properties(); + return props & (kLeftSemiring | kRightSemiring | + kCommutative | kIdempotent); + } + + SparsePowerWeight<W, K> Quantize(float delta = kDelta) const { + return SparseTupleWeight<W, K>::Quantize(delta); + } + + ReverseWeight Reverse() const { + return SparseTupleWeight<W, K>::Reverse(); + } +}; + +// Semimodule plus operation +template <class W, class K> +inline SparsePowerWeight<W, K> Plus(const SparsePowerWeight<W, K> &w1, + const SparsePowerWeight<W, K> &w2) { + SparsePowerWeight<W, K> ret; + SparseTupleWeightPlusMapper<W, K> operator_mapper; + SparseTupleWeightMap(&ret, w1, w2, operator_mapper); + return ret; +} + +// Semimodule times operation +template <class W, class K> +inline SparsePowerWeight<W, K> Times(const SparsePowerWeight<W, K> &w1, + const SparsePowerWeight<W, K> &w2) { + SparsePowerWeight<W, K> ret; + SparseTupleWeightTimesMapper<W, K> operator_mapper; + SparseTupleWeightMap(&ret, w1, w2, operator_mapper); + return ret; +} + +// Semimodule divide operation +template <class W, class K> +inline SparsePowerWeight<W, K> Divide(const SparsePowerWeight<W, K> &w1, + const SparsePowerWeight<W, K> &w2, + DivideType type = DIVIDE_ANY) { + SparsePowerWeight<W, K> ret; + SparseTupleWeightDivideMapper<W, K> operator_mapper(type); + SparseTupleWeightMap(&ret, w1, w2, operator_mapper); + return ret; +} + +// Semimodule dot product +template <class W, class K> +inline const W& DotProduct(const SparsePowerWeight<W, K> &w1, + const SparsePowerWeight<W, K> &w2) { + const SparsePowerWeight<W, K>& product = Times(w1, w2); + W ret(W::Zero()); + for (SparseTupleWeightIterator<W, K> it(product); !it.Done(); it.Next()) { + ret = Plus(ret, it.Value().second); + } + return ret; +} + +template <class W, class K> +inline bool ApproxEqual(const SparsePowerWeight<W, K> &w1, + const SparsePowerWeight<W, K> &w2, + float delta = kDelta) { + SparseTupleWeight<W, K> ret; + SparseTupleWeightApproxMapper<W, K> operator_mapper(kDelta); + SparseTupleWeightMap(&ret, w1, w2, operator_mapper); + return ret == SparsePowerWeight<W, K>::One(); +} + +template <class W, class K> +inline SparsePowerWeight<W, K> Times(const W &k, + const SparsePowerWeight<W, K> &w2) { + SparsePowerWeight<W, K> w1(k); + return Times(w1, w2); +} + +template <class W, class K> +inline SparsePowerWeight<W, K> Times(const SparsePowerWeight<W, K> &w1, + const W &k) { + SparsePowerWeight<W, K> w2(k); + return Times(w1, w2); +} + +template <class W, class K> +inline SparsePowerWeight<W, K> Divide(const SparsePowerWeight<W, K> &w1, + const W &k, + DivideType divide_type = DIVIDE_ANY) { + SparsePowerWeight<W, K> w2(k); + return Divide(w1, w2, divide_type); +} + +} // namespace fst + +#endif // FST_LIB_SPARSE_POWER_WEIGHT_H__ |