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Diffstat (limited to 'kaldi_io/src/tools/openfst/include/fst/random-weight.h')
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1 files changed, 348 insertions, 0 deletions
diff --git a/kaldi_io/src/tools/openfst/include/fst/random-weight.h b/kaldi_io/src/tools/openfst/include/fst/random-weight.h new file mode 100644 index 0000000..0ccd95d --- /dev/null +++ b/kaldi_io/src/tools/openfst/include/fst/random-weight.h @@ -0,0 +1,348 @@ +// random-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: riley@google.com (Michael Riley) +// +// \file +// Function objects to generate random weights in various semirings +// for testing purposes. + +#ifndef FST_LIB_RANDOM_WEIGHT_H__ +#define FST_LIB_RANDOM_WEIGHT_H__ + +#include <cstdlib> +#include <ctime> +#include <vector> +using std::vector; + + +#include <fst/float-weight.h> +#include <fst/product-weight.h> +#include <fst/string-weight.h> +#include <fst/lexicographic-weight.h> +#include <fst/power-weight.h> +#include <fst/signed-log-weight.h> +#include <fst/sparse-power-weight.h> + + +namespace fst { + +// The boolean 'allow_zero' below determines whether Zero() and zero +// divisors should be returned in the random weight generation. + +// This function object returns TropicalWeightTpl<T>'s that are random integers +// chosen from [0, kNumRandomWeights). +template <class T> +class TropicalWeightGenerator_ { + public: + typedef TropicalWeightTpl<T> Weight; + + TropicalWeightGenerator_(int seed = time(0), bool allow_zero = true) + : allow_zero_(allow_zero) { + srand(seed); + } + + Weight operator() () const { + int n = rand() % (kNumRandomWeights + allow_zero_); + if (allow_zero_ && n == kNumRandomWeights) + return Weight::Zero(); + + return Weight(static_cast<T>(n)); + } + + private: + // The number of alternative random weights. + static const int kNumRandomWeights = 5; + + bool allow_zero_; // permit Zero() and zero divisors +}; + +template <class T> const int TropicalWeightGenerator_<T>::kNumRandomWeights; + +typedef TropicalWeightGenerator_<float> TropicalWeightGenerator; + + +// This function object returns LogWeightTpl<T>'s that are random integers +// chosen from [0, kNumRandomWeights). +template <class T> +class LogWeightGenerator_ { + public: + typedef LogWeightTpl<T> Weight; + + LogWeightGenerator_(int seed = time(0), bool allow_zero = true) + : allow_zero_(allow_zero) { + srand(seed); + } + + Weight operator() () const { + int n = rand() % (kNumRandomWeights + allow_zero_); + if (allow_zero_ && n == kNumRandomWeights) + return Weight::Zero(); + + return Weight(static_cast<T>(n)); + } + + private: + // Number of alternative random weights. + static const int kNumRandomWeights = 5; + + bool allow_zero_; // permit Zero() and zero divisors +}; + +template <class T> const int LogWeightGenerator_<T>::kNumRandomWeights; + +typedef LogWeightGenerator_<float> LogWeightGenerator; + + +// This function object returns MinMaxWeightTpl<T>'s that are random integers +// chosen from (-kNumRandomWeights, kNumRandomWeights) in addition to +// One(), and Zero() if zero is allowed. +template <class T> +class MinMaxWeightGenerator_ { + public: + typedef MinMaxWeightTpl<T> Weight; + + MinMaxWeightGenerator_(int seed = time(0), bool allow_zero = true) + : allow_zero_(allow_zero) { + srand(seed); + } + + Weight operator() () const { + int n = (rand() % (2*kNumRandomWeights + allow_zero_)) - kNumRandomWeights; + if (allow_zero_ && n == kNumRandomWeights) + return Weight::Zero(); + else if (n == -kNumRandomWeights) + return Weight::One(); + + return Weight(static_cast<T>(n)); + } + + private: + // Parameters controlling the number of alternative random weights. + static const int kNumRandomWeights = 5; + + bool allow_zero_; // permit Zero() and zero divisors +}; + +template <class T> const int MinMaxWeightGenerator_<T>::kNumRandomWeights; + +typedef MinMaxWeightGenerator_<float> MinMaxWeightGenerator; + + +// This function object returns StringWeights that are random integer +// strings chosen from {1,...,kAlphabetSize}^{0,kMaxStringLength} U { Zero } +template <typename L, StringType S = STRING_LEFT> +class StringWeightGenerator { + public: + typedef StringWeight<L, S> Weight; + + StringWeightGenerator(int seed = time(0), bool allow_zero = true) + : allow_zero_(allow_zero) { + srand(seed); + } + + Weight operator() () const { + int n = rand() % (kMaxStringLength + allow_zero_); + if (allow_zero_ && n == kMaxStringLength) + return Weight::Zero(); + + vector<L> v; + for (int i = 0; i < n; ++i) + v.push_back(rand() % kAlphabetSize + 1); + return Weight(v.begin(), v.end()); + } + + private: + // Alphabet size for random weights. + static const int kAlphabetSize = 5; + // Number of alternative random weights. + static const int kMaxStringLength = 5; + + bool allow_zero_; // permit Zero() and zero +}; + +template <typename L, StringType S> +const int StringWeightGenerator<L, S>::kAlphabetSize; +template <typename L, StringType S> +const int StringWeightGenerator<L, S>::kMaxStringLength; + + +// This function object returns a weight generator over the product of the +// weights (by default) for the generators G1 and G2. +template <class G1, class G2, + class W = ProductWeight<typename G1::Weight, typename G2::Weight> > +class ProductWeightGenerator { + public: + typedef typename G1::Weight W1; + typedef typename G2::Weight W2; + typedef W Weight; + + ProductWeightGenerator(int seed = time(0), bool allow_zero = true) + : generator1_(seed, allow_zero), generator2_(seed, allow_zero) {} + + Weight operator() () const { + W1 w1 = generator1_(); + W2 w2 = generator2_(); + return Weight(w1, w2); + } + + private: + G1 generator1_; + G2 generator2_; +}; + + +// This function object returns a weight generator for a lexicographic weight +// composed out of weights for the generators G1 and G2. For lexicographic +// weights, we cannot generate zeroes for the two subweights separately: +// weights are members iff both members are zero or both members are non-zero. +template <class G1, class G2> +class LexicographicWeightGenerator { + public: + typedef typename G1::Weight W1; + typedef typename G2::Weight W2; + typedef LexicographicWeight<W1, W2> Weight; + + LexicographicWeightGenerator(int seed = time(0), bool allow_zero = true) + : generator1_(seed, false), generator2_(seed, false), + allow_zero_(allow_zero) {} + + Weight operator() () const { + if (allow_zero_) { + int n = rand() % (kNumRandomWeights + allow_zero_); + if (n == kNumRandomWeights) + return Weight(W1::Zero(), W2::Zero()); + } + W1 w1 = generator1_(); + W2 w2 = generator2_(); + return Weight(w1, w2); + } + + private: + G1 generator1_; + G2 generator2_; + static const int kNumRandomWeights = 5; + bool allow_zero_; +}; + +template <class G1, class G2> +const int LexicographicWeightGenerator<G1, G2>::kNumRandomWeights; + + +// Product generator of a string weight generator and an +// arbitrary weight generator. +template <class L, class G, StringType S = STRING_LEFT> +class GallicWeightGenerator + : public ProductWeightGenerator<StringWeightGenerator<L, S>, G> { + + public: + typedef ProductWeightGenerator<StringWeightGenerator<L, S>, G> PG; + typedef typename G::Weight W; + typedef GallicWeight<L, W, S> Weight; + + GallicWeightGenerator(int seed = time(0), bool allow_zero = true) + : PG(seed, allow_zero) {} + + GallicWeightGenerator(const PG &pg) : PG(pg) {} +}; + +// This function object returms a weight generator over the catersian power +// of rank n of the weights for the generator G. +template <class G, unsigned int n> +class PowerWeightGenerator { + public: + typedef typename G::Weight W; + typedef PowerWeight<W, n> Weight; + + PowerWeightGenerator(int seed = time(0), bool allow_zero = true) + : generator_(seed, allow_zero) {} + + Weight operator()() const { + Weight w; + for (size_t i = 0; i < n; ++i) { + W r = generator_(); + w.SetValue(i, r); + } + return w; + } + + private: + G generator_; +}; + +// This function object returns SignedLogWeightTpl<T>'s that are +// random integers chosen from [0, kNumRandomWeights). +// The sign is randomly chosen as well. +template <class T> +class SignedLogWeightGenerator_ { + public: + typedef SignedLogWeightTpl<T> Weight; + + SignedLogWeightGenerator_(int seed = time(0), bool allow_zero = true) + : allow_zero_(allow_zero) { + srand(seed); + } + + Weight operator() () const { + int m = rand() % 2; + int n = rand() % (kNumRandomWeights + allow_zero_); + + return SignedLogWeightTpl<T>( + (m == 0) ? + TropicalWeight(-1.0) : + TropicalWeight(1.0), + (allow_zero_ && n == kNumRandomWeights) ? + LogWeightTpl<T>::Zero() : + LogWeightTpl<T>(static_cast<T>(n))); + } + + private: + // Number of alternative random weights. + static const int kNumRandomWeights = 5; + bool allow_zero_; // permit Zero() and zero divisors +}; + +template <class T> const int SignedLogWeightGenerator_<T>::kNumRandomWeights; + +typedef SignedLogWeightGenerator_<float> SignedLogWeightGenerator; + +// This function object returms a weight generator over the catersian power +// of rank n of the weights for the generator G. +template <class G, class K, unsigned int n> +class SparsePowerWeightGenerator { + public: + typedef typename G::Weight W; + typedef SparsePowerWeight<W, K> Weight; + + SparsePowerWeightGenerator(int seed = time(0), bool allow_zero = true) + : generator_(seed, allow_zero) {} + + Weight operator()() const { + Weight w; + for (size_t i = 1; i <= n; ++i) { + W r = generator_(); + K p = i; + w.Push(p, r, true); + } + return w; + } + + private: + G generator_; +}; + +} // namespace fst + +#endif // FST_LIB_RANDOM_WEIGHT_H__ |