Drizzled Public API Documentation

ln.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 "ln.h"
23 
24 namespace drizzled
25 {
26 
29 {
30  assert(fixed == 1);
31  double value= args[0]->val_real();
32  if ((null_value= args[0]->null_value))
33  return 0.0;
34  if (value <= 0.0)
35  {
36  signal_divide_by_null();
37  return 0.0;
38  }
39  return log(value);
40 }
41 
42 } /* namespace drizzled */