1 // product-weight.h
2
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 //
15 // Copyright 2005-2010 Google, Inc.
16 // Author: riley@google.com (Michael Riley)
17 //
18 // \file
19 // Product weight set and associated semiring operation definitions.
20
21 #ifndef FST_LIB_PRODUCT_WEIGHT_H__
22 #define FST_LIB_PRODUCT_WEIGHT_H__
23
24 #include <stack>
25 #include <string>
26
27 #include <fst/pair-weight.h>
28 #include <fst/weight.h>
29
30
31 namespace fst {
32
33 // Product semiring: W1 * W2
34 template<class W1, class W2>
35 class ProductWeight : public PairWeight<W1, W2> {
36 public:
37 using PairWeight<W1, W2>::Zero;
38 using PairWeight<W1, W2>::One;
39 using PairWeight<W1, W2>::NoWeight;
40 using PairWeight<W1, W2>::Quantize;
41 using PairWeight<W1, W2>::Reverse;
42
43 typedef ProductWeight<typename W1::ReverseWeight, typename W2::ReverseWeight>
44 ReverseWeight;
45
ProductWeight()46 ProductWeight() {}
47
ProductWeight(const PairWeight<W1,W2> & w)48 ProductWeight(const PairWeight<W1, W2>& w) : PairWeight<W1, W2>(w) {}
49
ProductWeight(W1 w1,W2 w2)50 ProductWeight(W1 w1, W2 w2) : PairWeight<W1, W2>(w1, w2) {}
51
Zero()52 static const ProductWeight<W1, W2> &Zero() {
53 static const ProductWeight<W1, W2> zero(PairWeight<W1, W2>::Zero());
54 return zero;
55 }
56
One()57 static const ProductWeight<W1, W2> &One() {
58 static const ProductWeight<W1, W2> one(PairWeight<W1, W2>::One());
59 return one;
60 }
61
NoWeight()62 static const ProductWeight<W1, W2> &NoWeight() {
63 static const ProductWeight<W1, W2> no_weight(
64 PairWeight<W1, W2>::NoWeight());
65 return no_weight;
66 }
67
Type()68 static const string &Type() {
69 static const string type = W1::Type() + "_X_" + W2::Type();
70 return type;
71 }
72
Properties()73 static uint64 Properties() {
74 uint64 props1 = W1::Properties();
75 uint64 props2 = W2::Properties();
76 return props1 & props2 & (kLeftSemiring | kRightSemiring |
77 kCommutative | kIdempotent);
78 }
79
80 ProductWeight<W1, W2> Quantize(float delta = kDelta) const {
81 return PairWeight<W1, W2>::Quantize(delta);
82 }
83
Reverse()84 ReverseWeight Reverse() const {
85 return PairWeight<W1, W2>::Reverse();
86 }
87 };
88
89 template <class W1, class W2>
Plus(const ProductWeight<W1,W2> & w,const ProductWeight<W1,W2> & v)90 inline ProductWeight<W1, W2> Plus(const ProductWeight<W1, W2> &w,
91 const ProductWeight<W1, W2> &v) {
92 return ProductWeight<W1, W2>(Plus(w.Value1(), v.Value1()),
93 Plus(w.Value2(), v.Value2()));
94 }
95
96 template <class W1, class W2>
Times(const ProductWeight<W1,W2> & w,const ProductWeight<W1,W2> & v)97 inline ProductWeight<W1, W2> Times(const ProductWeight<W1, W2> &w,
98 const ProductWeight<W1, W2> &v) {
99 return ProductWeight<W1, W2>(Times(w.Value1(), v.Value1()),
100 Times(w.Value2(), v.Value2()));
101 }
102
103 template <class W1, class W2>
104 inline ProductWeight<W1, W2> Divide(const ProductWeight<W1, W2> &w,
105 const ProductWeight<W1, W2> &v,
106 DivideType typ = DIVIDE_ANY) {
107 return ProductWeight<W1, W2>(Divide(w.Value1(), v.Value1(), typ),
108 Divide(w.Value2(), v.Value2(), typ));
109 }
110
111 } // namespace fst
112
113 #endif // FST_LIB_PRODUCT_WEIGHT_H__
114