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
|
/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/* Written by Sergei A. Golubchik, who has a shared copyright to this code */
/* some definitions for full-text indices */
#include "fulltext.h"
#include <m_ctype.h>
#include <my_tree.h>
#define MIN_WORD_LEN 4
#define HYPHEN_IS_DELIM
#define HYPHEN_IS_CONCAT /* not used for now */
#define COMPILE_STOPWORDS_IN
/* Most of the formulae were shamelessly stolen from SMART distribution
ftp://ftp.cs.cornell.edu/pub/smart/smart.11.0.tar.Z
NORM_PIVOT was taken from the article
A.Singhal, C.Buckley, M.Mitra, "Pivoted Document Length Normalization",
ACM SIGIR'96, 21-29, 1996
*/
#define LWS_FOR_QUERY LWS_TF
#define LWS_IN_USE LWS_LOG
#define PRENORM_IN_USE PRENORM_AVG
#define NORM_IN_USE NORM_PIVOT
#define GWS_IN_USE GWS_PROB
/*==============================================================*/
#define LWS_TF (count)
#define LWS_BINARY (count>0)
#define LWS_SQUARE (count*count)
#define LWS_LOG (count?(log(count)+1):0)
/*--------------------------------------------------------------*/
#define PRENORM_NONE (p->weight)
#define PRENORM_MAX (p->weight/docstat.max)
#define PRENORM_AUG (0.4+0.6*p->weight/docstat.max)
#define PRENORM_AVG (p->weight/docstat.sum*docstat.uniq)
#define PRENORM_AVGLOG ((1+log(p->weight))/(1+log(docstat.sum/docstat.uniq)))
/*--------------------------------------------------------------*/
#define NORM_NONE (1)
#define NORM_SUM (docstat.nsum)
#define NORM_COS (sqrt(docstat.nsum2))
#ifdef EVAL_RUN
/*
extern ulong collstat;
#define PIVOT_STAT (docstat.uniq)
#define PIVOT_SLOPE (0.69)
#define PIVOT_PIVOT ((double)collstat/(info->state->records+1))
#define NORM_PIVOT ((1-PIVOT_SLOPE)*PIVOT_PIVOT+PIVOT_SLOPE*docstat.uniq)
*/
#endif /* EVAL_RUN */
#define PIVOT_VAL (0.0115)
#define NORM_PIVOT (1+PIVOT_VAL*docstat.uniq)
/*---------------------------------------------------------------*/
#define GWS_NORM (1/sqrt(sum2))
#define GWS_GFIDF (sum/doc_cnt)
/* Mysterious, but w/o (double) GWS_IDF performs better :-o */
#define GWS_IDF log(aio->info->state->records/doc_cnt)
#define GWS_IDF1 log((double)aio->info->state->records/doc_cnt)
#define GWS_PROB log(((double)(aio->info->state->records-doc_cnt))/doc_cnt)
#define GWS_FREQ (1.0/doc_cnt)
#define GWS_SQUARED pow(log((double)aio->info->state->records/doc_cnt),2)
#define GWS_CUBIC pow(log((double)aio->info->state->records/doc_cnt),3)
#define GWS_ENTROPY (1-(suml/sum-log(sum))/log(aio->info->state->records))
/*=================================================================*/
typedef struct st_ft_word {
byte * pos;
uint len;
double weight;
#ifdef EVAL_RUN
byte cnt;
#endif /* EVAL_RUN */
} FT_WORD;
int is_stopword(char *word, uint len);
uint _ft_make_key(MI_INFO *, uint , byte *, FT_WORD *, my_off_t);
TREE * ft_parse(TREE *, byte *, int);
FT_WORD * ft_linearize(MI_INFO *, uint, byte *, TREE *);
|
