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Diffstat (limited to 'kaldi_io/src/tools/openfst/include/fst/weight.h')
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diff --git a/kaldi_io/src/tools/openfst/include/fst/weight.h b/kaldi_io/src/tools/openfst/include/fst/weight.h deleted file mode 100644 index 7eb4bb1..0000000 --- a/kaldi_io/src/tools/openfst/include/fst/weight.h +++ /dev/null @@ -1,179 +0,0 @@ -// 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] (Michael Riley) -// -// \file -// General weight set and associated semiring operation definitions. -// -// A semiring is specified by two binary operations Plus and Times and -// two designated elements Zero and One with the following properties: -// Plus: associative, commutative, and has Zero as its identity. -// Times: associative and has identity One, distributes w.r.t. Plus, and -// has Zero as an annihilator: -// Times(Zero(), a) == Times(a, Zero()) = Zero(). -// -// A left semiring distributes on the left; a right semiring is -// similarly defined. -// -// A Weight class must have binary functions =Plus= and =Times= and -// static member functions =Zero()= and =One()= and these must form -// (at least) a left or right semiring. -// -// In addition, the following should be defined for a Weight: -// Member: predicate on set membership. -// NoWeight: static member function that returns an element that is -// not a set member; used to signal an error. -// >>: reads textual representation of a weight. -// <<: prints textual representation of a weight. -// Read(istream &strm): reads binary representation of a weight. -// Write(ostream &strm): writes binary representation of a weight. -// Hash: maps weight to size_t. -// ApproxEqual: approximate equality (for inexact weights) -// Quantize: quantizes wrt delta (for inexact weights) -// Divide: for all a,b,c s.t. Times(a, b) == c -// --> b' = Divide(c, a, DIVIDE_LEFT) if a left semiring, b'.Member() -// and Times(a, b') == c -// --> a' = Divide(c, b, DIVIDE_RIGHT) if a right semiring, a'.Member() -// and Times(a', b) == c -// --> b' = Divide(c, a) = Divide(c, a, DIVIDE_ANY) = -// Divide(c, a, DIVIDE_LEFT) = Divide(c, a, DIVIDE_RIGHT) if a -// commutative semiring, b'.Member() and Times(a, b') = Times(b', a) = c -// ReverseWeight: the type of the corresponding reverse weight. -// Typically the same type as Weight for a (both left and right) semiring. -// For the left string semiring, it is the right string semiring. -// Reverse: a mapping from Weight to ReverseWeight s.t. -// --> Reverse(Reverse(a)) = a -// --> Reverse(Plus(a, b)) = Plus(Reverse(a), Reverse(b)) -// --> Reverse(Times(a, b)) = Times(Reverse(b), Reverse(a)) -// Typically the identity mapping in a (both left and right) semiring. -// In the left string semiring, it maps to the reverse string -// in the right string semiring. -// Properties: specifies additional properties that hold: -// LeftSemiring: indicates weights form a left semiring. -// RightSemiring: indicates weights form a right semiring. -// Commutative: for all a,b: Times(a,b) == Times(b,a) -// Idempotent: for all a: Plus(a, a) == a. -// Path: for all a, b: Plus(a, b) == a or Plus(a, b) == b. - - -#ifndef FST_LIB_WEIGHT_H__ -#define FST_LIB_WEIGHT_H__ - -#include <cmath> -#include <cctype> -#include <iostream> -#include <sstream> - -#include <fst/compat.h> - -#include <fst/util.h> - - -namespace fst { - -// -// CONSTANT DEFINITIONS -// - -// A representable float near .001 -const float kDelta = 1.0F/1024.0F; - -// For all a,b,c: Times(c, Plus(a,b)) = Plus(Times(c,a), Times(c, b)) -const uint64 kLeftSemiring = 0x0000000000000001ULL; - -// For all a,b,c: Times(Plus(a,b), c) = Plus(Times(a,c), Times(b, c)) -const uint64 kRightSemiring = 0x0000000000000002ULL; - -const uint64 kSemiring = kLeftSemiring | kRightSemiring; - -// For all a,b: Times(a,b) = Times(b,a) -const uint64 kCommutative = 0x0000000000000004ULL; - -// For all a: Plus(a, a) = a -const uint64 kIdempotent = 0x0000000000000008ULL; - -// For all a,b: Plus(a,b) = a or Plus(a,b) = b -const uint64 kPath = 0x0000000000000010ULL; - - -// Determines direction of division. -enum DivideType { DIVIDE_LEFT, // left division - DIVIDE_RIGHT, // right division - DIVIDE_ANY }; // division in a commutative semiring - -// NATURAL ORDER -// -// By definition: -// a <= b iff a + b = a -// The natural order is a negative partial order iff the semiring is -// idempotent. It is trivially monotonic for plus. It is left -// (resp. right) monotonic for times iff the semiring is left -// (resp. right) distributive. It is a total order iff the semiring -// has the path property. See Mohri, "Semiring Framework and -// Algorithms for Shortest-Distance Problems", Journal of Automata, -// Languages and Combinatorics 7(3):321-350, 2002. We define the -// strict version of this order below. - -template <class W> -class NaturalLess { - public: - typedef W Weight; - - NaturalLess() { - if (!(W::Properties() & kIdempotent)) { - FSTERROR() << "NaturalLess: Weight type is not idempotent: " - << W::Type(); - } - } - - bool operator()(const W &w1, const W &w2) const { - return (Plus(w1, w2) == w1) && w1 != w2; - } -}; - - -// Power is the iterated product for arbitrary semirings such that -// Power(w, 0) is One() for the semiring, and -// Power(w, n) = Times(Power(w, n-1), w) - -template <class W> -W Power(W w, size_t n) { - W result = W::One(); - for (size_t i = 0; i < n; ++i) { - result = Times(result, w); - } - return result; -} - -// General weight converter - raises error. -template <class W1, class W2> -struct WeightConvert { - W2 operator()(W1 w1) const { - FSTERROR() << "WeightConvert: can't convert weight from \"" - << W1::Type() << "\" to \"" << W2::Type(); - return W2::NoWeight(); - } -}; - -// Specialized weight converter to self. -template <class W> -struct WeightConvert<W, W> { - W operator()(W w) const { return w; } -}; - -} // namespace fst - -#endif // FST_LIB_WEIGHT_H__ |