Drizzled Public API Documentation

log.cc
1 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
2  * vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
3  *
4  * Copyright (C) 2008 Sun Microsystems, Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; version 2 of the License.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18  */
19 
20 #include <config.h>
21 #include <math.h>
22 #include "log.h"
23 
24 namespace drizzled
25 {
26 
34 {
35  assert(fixed == 1);
36  double value= args[0]->val_real();
37  if ((null_value= args[0]->null_value))
38  return 0.0;
39  if (value <= 0.0)
40  {
41  signal_divide_by_null();
42  return 0.0;
43  }
44  if (arg_count == 2)
45  {
46  double value2= args[1]->val_real();
47  if ((null_value= args[1]->null_value))
48  return 0.0;
49  if (value2 <= 0.0 || value == 1.0)
50  {
51  signal_divide_by_null();
52  return 0.0;
53  }
54  return log(value2) / log(value);
55  }
56  return log(value);
57 }
58 
60 {
61  assert(fixed == 1);
62  double value= args[0]->val_real();
63 
64  if ((null_value=args[0]->null_value))
65  return 0.0;
66  if (value <= 0.0)
67  {
68  signal_divide_by_null();
69  return 0.0;
70  }
71  return log(value) / M_LN2;
72 }
73 
75 {
76  assert(fixed == 1);
77  double value= args[0]->val_real();
78  if ((null_value= args[0]->null_value))
79  return 0.0;
80  if (value <= 0.0)
81  {
82  signal_divide_by_null();
83  return 0.0;
84  }
85  return log10(value);
86 }
87 
88 } /* namespace drizzled */
bool fixed
Definition: item.h:120
bool null_value
Definition: item.h:122
double val_real()
Definition: log.cc:33
virtual double val_real()=0
double val_real()
Definition: log.cc:59