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492.3.9
by Lee
code clean move Item_func_abs, Item_func_int_exp, Item_func_ln, Item_func_log to functions directory |
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/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
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* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
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*
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* Copyright (C) 2008 Sun Microsystems
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include <drizzled/server_includes.h> |
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642.1.30
by Lee
move math functions to drizzled/function/math directory |
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#include <drizzled/function/math/log.h> |
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492.3.9
by Lee
code clean move Item_func_abs, Item_func_int_exp, Item_func_ln, Item_func_log to functions directory |
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/**
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Extended but so slower LOG function.
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We have to check if all values are > zero and first one is not one
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as these are the cases then result is not a number.
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*/
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double Item_func_log::val_real() |
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{
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assert(fixed == 1); |
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double value= args[0]->val_real(); |
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if ((null_value= args[0]->null_value)) |
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return 0.0; |
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if (value <= 0.0) |
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{
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signal_divide_by_null(); |
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return 0.0; |
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}
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if (arg_count == 2) |
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{
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double value2= args[1]->val_real(); |
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if ((null_value= args[1]->null_value)) |
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return 0.0; |
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if (value2 <= 0.0 || value == 1.0) |
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{
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signal_divide_by_null(); |
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return 0.0; |
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}
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return log(value2) / log(value); |
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}
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return log(value); |
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}
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double Item_func_log2::val_real() |
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{
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assert(fixed == 1); |
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double value= args[0]->val_real(); |
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if ((null_value=args[0]->null_value)) |
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return 0.0; |
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if (value <= 0.0) |
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{
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signal_divide_by_null(); |
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return 0.0; |
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}
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return log(value) / M_LN2; |
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}
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double Item_func_log10::val_real() |
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{
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assert(fixed == 1); |
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double value= args[0]->val_real(); |
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if ((null_value= args[0]->null_value)) |
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return 0.0; |
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if (value <= 0.0) |
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{
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signal_divide_by_null(); |
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return 0.0; |
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}
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return log10(value); |
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}
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