00001 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*- 00002 * vim:expandtab:shiftwidth=2:tabstop=2:smarttab: 00003 * 00004 * Copyright (C) 2008 Sun Microsystems, Inc. 00005 * 00006 * This program is free software; you can redistribute it and/or modify 00007 * it under the terms of the GNU General Public License as published by 00008 * the Free Software Foundation; version 2 of the License. 00009 * 00010 * This program is distributed in the hope that it will be useful, 00011 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00013 * GNU General Public License for more details. 00014 * 00015 * You should have received a copy of the GNU General Public License 00016 * along with this program; if not, write to the Free Software 00017 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 00018 */ 00019 00020 #include <config.h> 00021 #include <math.h> 00022 #include "ln.h" 00023 00024 namespace drizzled 00025 { 00026 00028 double Item_func_ln::val_real() 00029 { 00030 assert(fixed == 1); 00031 double value= args[0]->val_real(); 00032 if ((null_value= args[0]->null_value)) 00033 return 0.0; 00034 if (value <= 0.0) 00035 { 00036 signal_divide_by_null(); 00037 return 0.0; 00038 } 00039 return log(value); 00040 } 00041 00042 } /* namespace drizzled */