LCOV - code coverage report
Current view: top level - expand - bo1eweight.cc (source / functions) Hit Total Coverage
Test: Test Coverage for xapian-core 7028d852e609 Lines: 6 6 100.0 %
Date: 2019-02-17 14:59:59 Functions: 1 1 100.0 %
Branches: 0 0 -

           Branch data     Line data    Source code
       1                 :            : /** @file bo1eweight.cc
       2                 :            :  * @brief Xapian::Bo1EWeight class - The Bo1 scheme of the DFR framework
       3                 :            :  *                                   for query expansion.
       4                 :            :  */
       5                 :            : /* Copyright (C) 2013 Aarsh Shah
       6                 :            :  *
       7                 :            :  * This program is free software; you can redistribute it and/or
       8                 :            :  * modify it under the terms of the GNU General Public License as
       9                 :            :  * published by the Free Software Foundation; either version 2 of the
      10                 :            :  * License, or (at your option) any later version.
      11                 :            :  *
      12                 :            :  * This program is distributed in the hope that it will be useful
      13                 :            :  * but WITHOUT ANY WARRANTY; without even the implied warranty of
      14                 :            :  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
      15                 :            :  * GNU General Public License for more details.
      16                 :            :  *
      17                 :            :  * You should have received a copy of the GNU General Public License
      18                 :            :  * along with this program; if not, write to the Free Software
      19                 :            :  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
      20                 :            :  */
      21                 :            : 
      22                 :            : #include <config.h>
      23                 :            : 
      24                 :            : #include "expandweight.h"
      25                 :            : #include "common/log2.h"
      26                 :            : 
      27                 :            : using namespace std;
      28                 :            : 
      29                 :            : namespace Xapian {
      30                 :            : namespace Internal {
      31                 :            : 
      32                 :            : double
      33                 :        469 : Bo1EWeight::get_weight() const
      34                 :            : {
      35                 :        469 :     double F = get_collection_freq();
      36                 :            : 
      37                 :        469 :     double N = get_dbsize();
      38                 :            : 
      39                 :        469 :     double mean = F / N;
      40                 :        469 :     double wt = stats.rcollection_freq * log2((1.0 + mean) / mean) + log2(1.0 + mean);
      41                 :            : 
      42                 :        469 :     return wt;
      43                 :            : }
      44                 :            : 
      45                 :            : }
      46                 :            : }

Generated by: LCOV version 1.11