forked from blevesearch/bleve
-
Notifications
You must be signed in to change notification settings - Fork 0
/
scorer_term.go
175 lines (151 loc) · 4.93 KB
/
scorer_term.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
// Copyright (c) 2014 Couchbase, Inc.
// 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.
package scorers
import (
"fmt"
"math"
"github.com/blevesearch/bleve/index"
"github.com/blevesearch/bleve/search"
)
type TermQueryScorer struct {
queryTerm string
queryField string
queryBoost float64
docTerm uint64
docTotal uint64
idf float64
explain bool
idfExplanation *search.Explanation
queryNorm float64
queryWeight float64
queryWeightExplanation *search.Explanation
}
func NewTermQueryScorer(queryTerm string, queryField string, queryBoost float64, docTotal, docTerm uint64, explain bool) *TermQueryScorer {
rv := TermQueryScorer{
queryTerm: queryTerm,
queryField: queryField,
queryBoost: queryBoost,
docTerm: docTerm,
docTotal: docTotal,
idf: 1.0 + math.Log(float64(docTotal)/float64(docTerm+1.0)),
explain: explain,
queryWeight: 1.0,
}
if explain {
rv.idfExplanation = &search.Explanation{
Value: rv.idf,
Message: fmt.Sprintf("idf(docFreq=%d, maxDocs=%d)", docTerm, docTotal),
}
}
return &rv
}
func (s *TermQueryScorer) Weight() float64 {
sum := s.queryBoost * s.idf
return sum * sum
}
func (s *TermQueryScorer) SetQueryNorm(qnorm float64) {
s.queryNorm = qnorm
// update the query weight
s.queryWeight = s.queryBoost * s.idf * s.queryNorm
if s.explain {
childrenExplanations := make([]*search.Explanation, 3)
childrenExplanations[0] = &search.Explanation{
Value: s.queryBoost,
Message: "boost",
}
childrenExplanations[1] = s.idfExplanation
childrenExplanations[2] = &search.Explanation{
Value: s.queryNorm,
Message: "queryNorm",
}
s.queryWeightExplanation = &search.Explanation{
Value: s.queryWeight,
Message: fmt.Sprintf("queryWeight(%s:%s^%f), product of:", s.queryField, string(s.queryTerm), s.queryBoost),
Children: childrenExplanations,
}
}
}
func (s *TermQueryScorer) Score(ctx *search.SearchContext, termMatch *index.TermFieldDoc) *search.DocumentMatch {
var scoreExplanation *search.Explanation
// need to compute score
var tf float64
if termMatch.Freq < MaxSqrtCache {
tf = SqrtCache[int(termMatch.Freq)]
} else {
tf = math.Sqrt(float64(termMatch.Freq))
}
score := tf * termMatch.Norm * s.idf
if s.explain {
childrenExplanations := make([]*search.Explanation, 3)
childrenExplanations[0] = &search.Explanation{
Value: tf,
Message: fmt.Sprintf("tf(termFreq(%s:%s)=%d", s.queryField, string(s.queryTerm), termMatch.Freq),
}
childrenExplanations[1] = &search.Explanation{
Value: termMatch.Norm,
Message: fmt.Sprintf("fieldNorm(field=%s, doc=%s)", s.queryField, termMatch.ID),
}
childrenExplanations[2] = s.idfExplanation
scoreExplanation = &search.Explanation{
Value: score,
Message: fmt.Sprintf("fieldWeight(%s:%s in %s), product of:", s.queryField, string(s.queryTerm), termMatch.ID),
Children: childrenExplanations,
}
}
// if the query weight isn't 1, multiply
if s.queryWeight != 1.0 {
score = score * s.queryWeight
if s.explain {
childExplanations := make([]*search.Explanation, 2)
childExplanations[0] = s.queryWeightExplanation
childExplanations[1] = scoreExplanation
scoreExplanation = &search.Explanation{
Value: score,
Message: fmt.Sprintf("weight(%s:%s^%f in %s), product of:", s.queryField, string(s.queryTerm), s.queryBoost, termMatch.ID),
Children: childExplanations,
}
}
}
rv := ctx.DocumentMatchPool.Get()
rv.IndexInternalID = append(rv.IndexInternalID, termMatch.ID...)
rv.Score = score
if s.explain {
rv.Expl = scoreExplanation
}
if termMatch.Vectors != nil && len(termMatch.Vectors) > 0 {
rv.Locations = make(search.FieldTermLocationMap)
for _, v := range termMatch.Vectors {
tlm := rv.Locations[v.Field]
if tlm == nil {
tlm = make(search.TermLocationMap)
}
loc := search.Location{
Pos: float64(v.Pos),
Start: float64(v.Start),
End: float64(v.End),
}
if len(v.ArrayPositions) > 0 {
loc.ArrayPositions = make([]float64, len(v.ArrayPositions))
for i, ap := range v.ArrayPositions {
loc.ArrayPositions[i] = float64(ap)
}
}
locations := tlm[s.queryTerm]
if locations == nil {
locations = make(search.Locations, 1)
locations[0] = &loc
} else {
locations = append(locations, &loc)
}
tlm[s.queryTerm] = locations
rv.Locations[v.Field] = tlm
}
}
return rv
}