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996 lines
36 KiB
PHP
996 lines
36 KiB
PHP
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<?php
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/**
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* Class for parsing Excel formulas
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*
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* License Information:
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*
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* Spreadsheet::WriteExcel: A library for generating Excel Spreadsheets
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* Copyright (C) 2002 Xavier Noguer xnoguer@rezebra.com
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library 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 GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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/**
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* @const ADD token identifier for character "+"
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*/
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define('ADD',"+");
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/**
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* @const SUB token identifier for character "-"
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*/
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define('SUB',"-");
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/**
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* @const EQUAL token identifier for character "="
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*/
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define('EQUAL',"=");
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/**
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* @const MUL token identifier for character "*"
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*/
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define('MUL',"*");
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/**
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* @const DIV token identifier for character "/"
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*/
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define('DIV',"/");
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/**
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* @const OPEN token identifier for character "("
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*/
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define('OPEN',"(");
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/**
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* @const CLOSE token identifier for character ")"
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*/
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define('CLOSE',")");
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/**
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* @const COMA token identifier for character ","
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*/
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define('COMA',",");
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/**
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* Class for parsing Excel formulas
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*
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* @author Xavier Noguer <xnoguer@rezebra.com>
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* @package Spreadsheet_WriteExcel
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*/
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class Parser
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{
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/**
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* The class constructor
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*
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* @param integer $byte_order The byte order (Little endian or Big endian) of the architecture
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(optional). 1 => big endian, 0 (default) => little endian.
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*/
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function Parser($byte_order = 0)
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{
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$this->_current_char = 0; // The index of the character we are currently looking at.
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$this->_current_token = ''; // The token we are working on.
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$this->_formula = ""; // The formula to parse.
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$this->_lookahead = ''; // The character ahead of the current char.
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$this->_parse_tree = ''; // The parse tree to be generated.
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$this->_initialize_hashes(); // Initialize the hashes: ptg's and function's ptg's
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$this->_byte_order = $byte_order; // Little Endian or Big Endian
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$this->_func_args = 0; // Number of arguments for the current function
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$this->_volatile = 0;
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}
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/**
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* Initialize the ptg and function hashes.
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*/
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function _initialize_hashes()
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{
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// The Excel ptg indices
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$this->ptg = array(
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'ptgExp' => 0x01,
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'ptgTbl' => 0x02,
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'ptgAdd' => 0x03,
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'ptgSub' => 0x04,
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'ptgMul' => 0x05,
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'ptgDiv' => 0x06,
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'ptgPower' => 0x07,
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'ptgConcat' => 0x08,
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'ptgLT' => 0x09,
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'ptgLE' => 0x0A,
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'ptgEQ' => 0x0B,
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'ptgGE' => 0x0C,
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'ptgGT' => 0x0D,
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'ptgNE' => 0x0E,
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'ptgIsect' => 0x0F,
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'ptgUnion' => 0x10,
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'ptgRange' => 0x11,
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'ptgUplus' => 0x12,
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'ptgUminus' => 0x13,
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'ptgPercent' => 0x14,
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'ptgParen' => 0x15,
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'ptgMissArg' => 0x16,
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'ptgStr' => 0x17,
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'ptgAttr' => 0x19,
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'ptgSheet' => 0x1A,
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'ptgEndSheet' => 0x1B,
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'ptgErr' => 0x1C,
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'ptgBool' => 0x1D,
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'ptgInt' => 0x1E,
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'ptgNum' => 0x1F,
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'ptgArray' => 0x20,
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'ptgFunc' => 0x21,
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'ptgFuncVar' => 0x22,
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'ptgName' => 0x23,
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'ptgRef' => 0x24,
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'ptgArea' => 0x25,
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'ptgMemArea' => 0x26,
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'ptgMemErr' => 0x27,
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'ptgMemNoMem' => 0x28,
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'ptgMemFunc' => 0x29,
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'ptgRefErr' => 0x2A,
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'ptgAreaErr' => 0x2B,
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'ptgRefN' => 0x2C,
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'ptgAreaN' => 0x2D,
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'ptgMemAreaN' => 0x2E,
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'ptgMemNoMemN' => 0x2F,
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'ptgNameX' => 0x39,
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'ptgRef3d' => 0x3A,
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'ptgArea3d' => 0x3B,
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'ptgRefErr3d' => 0x3C,
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'ptgAreaErr3d' => 0x3D,
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'ptgArrayV' => 0x40,
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'ptgFuncV' => 0x41,
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'ptgFuncVarV' => 0x42,
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'ptgNameV' => 0x43,
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'ptgRefV' => 0x44,
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'ptgAreaV' => 0x45,
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'ptgMemAreaV' => 0x46,
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'ptgMemErrV' => 0x47,
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'ptgMemNoMemV' => 0x48,
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'ptgMemFuncV' => 0x49,
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'ptgRefErrV' => 0x4A,
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'ptgAreaErrV' => 0x4B,
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'ptgRefNV' => 0x4C,
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'ptgAreaNV' => 0x4D,
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'ptgMemAreaNV' => 0x4E,
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'ptgMemNoMemN' => 0x4F,
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'ptgFuncCEV' => 0x58,
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'ptgNameXV' => 0x59,
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'ptgRef3dV' => 0x5A,
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'ptgArea3dV' => 0x5B,
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'ptgRefErr3dV' => 0x5C,
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'ptgAreaErr3d' => 0x5D,
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'ptgArrayA' => 0x60,
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'ptgFuncA' => 0x61,
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'ptgFuncVarA' => 0x62,
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'ptgNameA' => 0x63,
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'ptgRefA' => 0x64,
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'ptgAreaA' => 0x65,
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'ptgMemAreaA' => 0x66,
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'ptgMemErrA' => 0x67,
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'ptgMemNoMemA' => 0x68,
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'ptgMemFuncA' => 0x69,
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'ptgRefErrA' => 0x6A,
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'ptgAreaErrA' => 0x6B,
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'ptgRefNA' => 0x6C,
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'ptgAreaNA' => 0x6D,
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'ptgMemAreaNA' => 0x6E,
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'ptgMemNoMemN' => 0x6F,
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'ptgFuncCEA' => 0x78,
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'ptgNameXA' => 0x79,
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'ptgRef3dA' => 0x7A,
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'ptgArea3dA' => 0x7B,
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'ptgRefErr3dA' => 0x7C,
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'ptgAreaErr3d' => 0x7D
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);
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// Thanks to Michael Meeks and Gnumeric for the initial arg values.
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//
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// The following hash was generated by "function_locale.pl" in the distro.
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// Refer to function_locale.pl for non-English function names.
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//
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// The array elements are as follow:
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// ptg: The Excel function ptg code.
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// args: The number of arguments that the function takes:
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// >=0 is a fixed number of arguments.
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// -1 is a variable number of arguments.
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// class: The reference, value or array class of the function args.
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// vol: The function is volatile.
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//
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$this->_functions = array(
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// function ptg args class vol
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'COUNT' => array( 0, -1, 0, 0 ),
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'IF' => array( 1, -1, 1, 0 ),
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'ISNA' => array( 2, 1, 1, 0 ),
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'ISERROR' => array( 3, 1, 1, 0 ),
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'SUM' => array( 4, -1, 0, 0 ),
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'AVERAGE' => array( 5, -1, 0, 0 ),
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'MIN' => array( 6, -1, 0, 0 ),
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'MAX' => array( 7, -1, 0, 0 ),
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'ROW' => array( 8, -1, 0, 0 ),
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'COLUMN' => array( 9, -1, 0, 0 ),
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'NA' => array( 10, 0, 0, 0 ),
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'NPV' => array( 11, -1, 1, 0 ),
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'STDEV' => array( 12, -1, 0, 0 ),
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'DOLLAR' => array( 13, -1, 1, 0 ),
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'FIXED' => array( 14, -1, 1, 0 ),
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'SIN' => array( 15, 1, 1, 0 ),
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'COS' => array( 16, 1, 1, 0 ),
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'TAN' => array( 17, 1, 1, 0 ),
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'ATAN' => array( 18, 1, 1, 0 ),
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'PI' => array( 19, 0, 1, 0 ),
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'SQRT' => array( 20, 1, 1, 0 ),
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'EXP' => array( 21, 1, 1, 0 ),
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'LN' => array( 22, 1, 1, 0 ),
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'LOG10' => array( 23, 1, 1, 0 ),
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'ABS' => array( 24, 1, 1, 0 ),
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'INT' => array( 25, 1, 1, 0 ),
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'SIGN' => array( 26, 1, 1, 0 ),
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'ROUND' => array( 27, 2, 1, 0 ),
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'LOOKUP' => array( 28, -1, 0, 0 ),
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'INDEX' => array( 29, -1, 0, 1 ),
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'REPT' => array( 30, 2, 1, 0 ),
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'MID' => array( 31, 3, 1, 0 ),
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'LEN' => array( 32, 1, 1, 0 ),
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'VALUE' => array( 33, 1, 1, 0 ),
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'TRUE' => array( 34, 0, 1, 0 ),
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'FALSE' => array( 35, 0, 1, 0 ),
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'AND' => array( 36, -1, 0, 0 ),
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'OR' => array( 37, -1, 0, 0 ),
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'NOT' => array( 38, 1, 1, 0 ),
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'MOD' => array( 39, 2, 1, 0 ),
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'DCOUNT' => array( 40, 3, 0, 0 ),
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'DSUM' => array( 41, 3, 0, 0 ),
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'DAVERAGE' => array( 42, 3, 0, 0 ),
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'DMIN' => array( 43, 3, 0, 0 ),
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'DMAX' => array( 44, 3, 0, 0 ),
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'DSTDEV' => array( 45, 3, 0, 0 ),
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'VAR' => array( 46, -1, 0, 0 ),
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'DVAR' => array( 47, 3, 0, 0 ),
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'TEXT' => array( 48, 2, 1, 0 ),
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'LINEST' => array( 49, -1, 0, 0 ),
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'TREND' => array( 50, -1, 0, 0 ),
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'LOGEST' => array( 51, -1, 0, 0 ),
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'GROWTH' => array( 52, -1, 0, 0 ),
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'PV' => array( 56, -1, 1, 0 ),
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'FV' => array( 57, -1, 1, 0 ),
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'NPER' => array( 58, -1, 1, 0 ),
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'PMT' => array( 59, -1, 1, 0 ),
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'RATE' => array( 60, -1, 1, 0 ),
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'MIRR' => array( 61, 3, 0, 0 ),
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'IRR' => array( 62, -1, 0, 0 ),
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'RAND' => array( 63, 0, 1, 1 ),
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'MATCH' => array( 64, -1, 0, 0 ),
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'DATE' => array( 65, 3, 1, 0 ),
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'TIME' => array( 66, 3, 1, 0 ),
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'DAY' => array( 67, 1, 1, 0 ),
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'MONTH' => array( 68, 1, 1, 0 ),
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'YEAR' => array( 69, 1, 1, 0 ),
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'WEEKDAY' => array( 70, -1, 1, 0 ),
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'HOUR' => array( 71, 1, 1, 0 ),
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'MINUTE' => array( 72, 1, 1, 0 ),
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'SECOND' => array( 73, 1, 1, 0 ),
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'NOW' => array( 74, 0, 1, 1 ),
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'AREAS' => array( 75, 1, 0, 1 ),
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'ROWS' => array( 76, 1, 0, 1 ),
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'COLUMNS' => array( 77, 1, 0, 1 ),
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'OFFSET' => array( 78, -1, 0, 1 ),
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'SEARCH' => array( 82, -1, 1, 0 ),
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'TRANSPOSE' => array( 83, 1, 1, 0 ),
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'TYPE' => array( 86, 1, 1, 0 ),
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'ATAN2' => array( 97, 2, 1, 0 ),
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'ASIN' => array( 98, 1, 1, 0 ),
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'ACOS' => array( 99, 1, 1, 0 ),
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'CHOOSE' => array( 100, -1, 1, 0 ),
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'HLOOKUP' => array( 101, -1, 0, 0 ),
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'VLOOKUP' => array( 102, -1, 0, 0 ),
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'ISREF' => array( 105, 1, 0, 0 ),
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'LOG' => array( 109, -1, 1, 0 ),
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'CHAR' => array( 111, 1, 1, 0 ),
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'LOWER' => array( 112, 1, 1, 0 ),
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'UPPER' => array( 113, 1, 1, 0 ),
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'PROPER' => array( 114, 1, 1, 0 ),
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'LEFT' => array( 115, -1, 1, 0 ),
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'RIGHT' => array( 116, -1, 1, 0 ),
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'EXACT' => array( 117, 2, 1, 0 ),
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'TRIM' => array( 118, 1, 1, 0 ),
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'REPLACE' => array( 119, 4, 1, 0 ),
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'SUBSTITUTE' => array( 120, -1, 1, 0 ),
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'CODE' => array( 121, 1, 1, 0 ),
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'FIND' => array( 124, -1, 1, 0 ),
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'CELL' => array( 125, -1, 0, 1 ),
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'ISERR' => array( 126, 1, 1, 0 ),
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'ISTEXT' => array( 127, 1, 1, 0 ),
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'ISNUMBER' => array( 128, 1, 1, 0 ),
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'ISBLANK' => array( 129, 1, 1, 0 ),
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'T' => array( 130, 1, 0, 0 ),
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'N' => array( 131, 1, 0, 0 ),
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'DATEVALUE' => array( 140, 1, 1, 0 ),
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'TIMEVALUE' => array( 141, 1, 1, 0 ),
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'SLN' => array( 142, 3, 1, 0 ),
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'SYD' => array( 143, 4, 1, 0 ),
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'DDB' => array( 144, -1, 1, 0 ),
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'INDIRECT' => array( 148, -1, 1, 1 ),
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'CALL' => array( 150, -1, 1, 0 ),
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'CLEAN' => array( 162, 1, 1, 0 ),
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'MDETERM' => array( 163, 1, 2, 0 ),
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'MINVERSE' => array( 164, 1, 2, 0 ),
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'MMULT' => array( 165, 2, 2, 0 ),
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'IPMT' => array( 167, -1, 1, 0 ),
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'PPMT' => array( 168, -1, 1, 0 ),
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'COUNTA' => array( 169, -1, 0, 0 ),
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'PRODUCT' => array( 183, -1, 0, 0 ),
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'FACT' => array( 184, 1, 1, 0 ),
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'DPRODUCT' => array( 189, 3, 0, 0 ),
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'ISNONTEXT' => array( 190, 1, 1, 0 ),
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'STDEVP' => array( 193, -1, 0, 0 ),
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'VARP' => array( 194, -1, 0, 0 ),
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'DSTDEVP' => array( 195, 3, 0, 0 ),
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'DVARP' => array( 196, 3, 0, 0 ),
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'TRUNC' => array( 197, -1, 1, 0 ),
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'ISLOGICAL' => array( 198, 1, 1, 0 ),
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'DCOUNTA' => array( 199, 3, 0, 0 ),
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'ROUNDUP' => array( 212, 2, 1, 0 ),
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'ROUNDDOWN' => array( 213, 2, 1, 0 ),
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'RANK' => array( 216, -1, 0, 0 ),
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'ADDRESS' => array( 219, -1, 1, 0 ),
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'DAYS360' => array( 220, -1, 1, 0 ),
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|||
|
'TODAY' => array( 221, 0, 1, 1 ),
|
|||
|
'VDB' => array( 222, -1, 1, 0 ),
|
|||
|
'MEDIAN' => array( 227, -1, 0, 0 ),
|
|||
|
'SUMPRODUCT' => array( 228, -1, 2, 0 ),
|
|||
|
'SINH' => array( 229, 1, 1, 0 ),
|
|||
|
'COSH' => array( 230, 1, 1, 0 ),
|
|||
|
'TANH' => array( 231, 1, 1, 0 ),
|
|||
|
'ASINH' => array( 232, 1, 1, 0 ),
|
|||
|
'ACOSH' => array( 233, 1, 1, 0 ),
|
|||
|
'ATANH' => array( 234, 1, 1, 0 ),
|
|||
|
'DGET' => array( 235, 3, 0, 0 ),
|
|||
|
'INFO' => array( 244, 1, 1, 1 ),
|
|||
|
'DB' => array( 247, -1, 1, 0 ),
|
|||
|
'FREQUENCY' => array( 252, 2, 0, 0 ),
|
|||
|
'ERROR.TYPE' => array( 261, 1, 1, 0 ),
|
|||
|
'REGISTER.ID' => array( 267, -1, 1, 0 ),
|
|||
|
'AVEDEV' => array( 269, -1, 0, 0 ),
|
|||
|
'BETADIST' => array( 270, -1, 1, 0 ),
|
|||
|
'GAMMALN' => array( 271, 1, 1, 0 ),
|
|||
|
'BETAINV' => array( 272, -1, 1, 0 ),
|
|||
|
'BINOMDIST' => array( 273, 4, 1, 0 ),
|
|||
|
'CHIDIST' => array( 274, 2, 1, 0 ),
|
|||
|
'CHIINV' => array( 275, 2, 1, 0 ),
|
|||
|
'COMBIN' => array( 276, 2, 1, 0 ),
|
|||
|
'CONFIDENCE' => array( 277, 3, 1, 0 ),
|
|||
|
'CRITBINOM' => array( 278, 3, 1, 0 ),
|
|||
|
'EVEN' => array( 279, 1, 1, 0 ),
|
|||
|
'EXPONDIST' => array( 280, 3, 1, 0 ),
|
|||
|
'FDIST' => array( 281, 3, 1, 0 ),
|
|||
|
'FINV' => array( 282, 3, 1, 0 ),
|
|||
|
'FISHER' => array( 283, 1, 1, 0 ),
|
|||
|
'FISHERINV' => array( 284, 1, 1, 0 ),
|
|||
|
'FLOOR' => array( 285, 2, 1, 0 ),
|
|||
|
'GAMMADIST' => array( 286, 4, 1, 0 ),
|
|||
|
'GAMMAINV' => array( 287, 3, 1, 0 ),
|
|||
|
'CEILING' => array( 288, 2, 1, 0 ),
|
|||
|
'HYPGEOMDIST' => array( 289, 4, 1, 0 ),
|
|||
|
'LOGNORMDIST' => array( 290, 3, 1, 0 ),
|
|||
|
'LOGINV' => array( 291, 3, 1, 0 ),
|
|||
|
'NEGBINOMDIST' => array( 292, 3, 1, 0 ),
|
|||
|
'NORMDIST' => array( 293, 4, 1, 0 ),
|
|||
|
'NORMSDIST' => array( 294, 1, 1, 0 ),
|
|||
|
'NORMINV' => array( 295, 3, 1, 0 ),
|
|||
|
'NORMSINV' => array( 296, 1, 1, 0 ),
|
|||
|
'STANDARDIZE' => array( 297, 3, 1, 0 ),
|
|||
|
'ODD' => array( 298, 1, 1, 0 ),
|
|||
|
'PERMUT' => array( 299, 2, 1, 0 ),
|
|||
|
'POISSON' => array( 300, 3, 1, 0 ),
|
|||
|
'TDIST' => array( 301, 3, 1, 0 ),
|
|||
|
'WEIBULL' => array( 302, 4, 1, 0 ),
|
|||
|
'SUMXMY2' => array( 303, 2, 2, 0 ),
|
|||
|
'SUMX2MY2' => array( 304, 2, 2, 0 ),
|
|||
|
'SUMX2PY2' => array( 305, 2, 2, 0 ),
|
|||
|
'CHITEST' => array( 306, 2, 2, 0 ),
|
|||
|
'CORREL' => array( 307, 2, 2, 0 ),
|
|||
|
'COVAR' => array( 308, 2, 2, 0 ),
|
|||
|
'FORECAST' => array( 309, 3, 2, 0 ),
|
|||
|
'FTEST' => array( 310, 2, 2, 0 ),
|
|||
|
'INTERCEPT' => array( 311, 2, 2, 0 ),
|
|||
|
'PEARSON' => array( 312, 2, 2, 0 ),
|
|||
|
'RSQ' => array( 313, 2, 2, 0 ),
|
|||
|
'STEYX' => array( 314, 2, 2, 0 ),
|
|||
|
'SLOPE' => array( 315, 2, 2, 0 ),
|
|||
|
'TTEST' => array( 316, 4, 2, 0 ),
|
|||
|
'PROB' => array( 317, -1, 2, 0 ),
|
|||
|
'DEVSQ' => array( 318, -1, 0, 0 ),
|
|||
|
'GEOMEAN' => array( 319, -1, 0, 0 ),
|
|||
|
'HARMEAN' => array( 320, -1, 0, 0 ),
|
|||
|
'SUMSQ' => array( 321, -1, 0, 0 ),
|
|||
|
'KURT' => array( 322, -1, 0, 0 ),
|
|||
|
'SKEW' => array( 323, -1, 0, 0 ),
|
|||
|
'ZTEST' => array( 324, -1, 0, 0 ),
|
|||
|
'LARGE' => array( 325, 2, 0, 0 ),
|
|||
|
'SMALL' => array( 326, 2, 0, 0 ),
|
|||
|
'QUARTILE' => array( 327, 2, 0, 0 ),
|
|||
|
'PERCENTILE' => array( 328, 2, 0, 0 ),
|
|||
|
'PERCENTRANK' => array( 329, -1, 0, 0 ),
|
|||
|
'MODE' => array( 330, -1, 2, 0 ),
|
|||
|
'TRIMMEAN' => array( 331, 2, 0, 0 ),
|
|||
|
'TINV' => array( 332, 2, 1, 0 ),
|
|||
|
'CONCATENATE' => array( 336, -1, 1, 0 ),
|
|||
|
'POWER' => array( 337, 2, 1, 0 ),
|
|||
|
'RADIANS' => array( 342, 1, 1, 0 ),
|
|||
|
'DEGREES' => array( 343, 1, 1, 0 ),
|
|||
|
'SUBTOTAL' => array( 344, -1, 0, 0 ),
|
|||
|
'SUMIF' => array( 345, -1, 0, 0 ),
|
|||
|
'COUNTIF' => array( 346, 2, 0, 0 ),
|
|||
|
'COUNTBLANK' => array( 347, 1, 0, 0 ),
|
|||
|
'ROMAN' => array( 354, -1, 1, 0 )
|
|||
|
);
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* Convert a token to the proper ptg value.
|
|||
|
*
|
|||
|
* @param mixed $token The token to convert.
|
|||
|
*/
|
|||
|
function _convert($token)
|
|||
|
{
|
|||
|
if(is_numeric($token))
|
|||
|
{
|
|||
|
return($this->_convert_number($token));
|
|||
|
}
|
|||
|
// match references like A1
|
|||
|
elseif(preg_match("/^([A-I]?[A-Z])(\d+)$/",$token))
|
|||
|
{
|
|||
|
return($this->_convert_ref2d($token));
|
|||
|
}
|
|||
|
// match ranges like A1:B2
|
|||
|
elseif(preg_match("/^([A-I]?[A-Z])(\d+)\:([A-I]?[A-Z])(\d+)$/",$token))
|
|||
|
{
|
|||
|
return($this->_convert_range2d($token));
|
|||
|
}
|
|||
|
// match ranges like A1..B2
|
|||
|
elseif(preg_match("/^([A-I]?[A-Z])(\d+)\.\.([A-I]?[A-Z])(\d+)$/",$token))
|
|||
|
{
|
|||
|
return($this->_convert_range2d($token));
|
|||
|
}
|
|||
|
elseif(isset($this->ptg[$token])) // operators (including parentheses)
|
|||
|
{
|
|||
|
return(pack("C", $this->ptg[$token]));
|
|||
|
}
|
|||
|
elseif(preg_match("/[A-Z0-9<>-<2D>\.]+/",$token))
|
|||
|
{
|
|||
|
return($this->_convert_function($token,$this->_func_args));
|
|||
|
}
|
|||
|
// if it's an argument, ignore the token (the argument remains)
|
|||
|
elseif($token == 'arg')
|
|||
|
{
|
|||
|
$this->_func_args++;
|
|||
|
return('');
|
|||
|
}
|
|||
|
die("Unknown token $token");
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* Convert a number token to ptgInt or ptgNum
|
|||
|
*
|
|||
|
* @param mixed $num an integer or double for conersion to its ptg value
|
|||
|
*/
|
|||
|
function _convert_number($num)
|
|||
|
{
|
|||
|
// Integer in the range 0..2**16-1
|
|||
|
if ((preg_match("/^\d+$/",$num)) and ($num <= 65535)) {
|
|||
|
return pack("Cv", $this->ptg['ptgInt'], $num);
|
|||
|
}
|
|||
|
else // A float
|
|||
|
{
|
|||
|
if($this->_byte_order) // if it's Big Endian
|
|||
|
{
|
|||
|
$num = strrev($num);
|
|||
|
}
|
|||
|
return pack("Cd", $this->ptg['ptgNum'], $num);
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* Convert a function to a ptgFunc or ptgFuncVarV depending on the number of
|
|||
|
* args that it takes.
|
|||
|
*
|
|||
|
* @param string $token The name of the function for convertion to ptg value.
|
|||
|
* @param integer $num_args The number of arguments the function recieves.
|
|||
|
*/
|
|||
|
function _convert_function($token, $num_args)
|
|||
|
{
|
|||
|
$this->_func_args = 0; // re initialize the number of arguments
|
|||
|
$args = $this->_functions[$token][1];
|
|||
|
$volatile = $this->_functions[$token][3];
|
|||
|
|
|||
|
if($volatile) {
|
|||
|
$this->_volatile = 1;
|
|||
|
}
|
|||
|
// Fixed number of args eg. TIME($i,$j,$k).
|
|||
|
if ($args >= 0)
|
|||
|
{
|
|||
|
return(pack("Cv", $this->ptg['ptgFuncV'], $this->_functions[$token][0]));
|
|||
|
}
|
|||
|
// Variable number of args eg. SUM($i,$j,$k, ..).
|
|||
|
if ($args == -1) {
|
|||
|
return(pack("CCv", $this->ptg['ptgFuncVarV'], $num_args, $this->_functions[$token][0]));
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* Convert an Excel range such as A1:D4 to a ptgRefV.
|
|||
|
*
|
|||
|
* @param string $range An Excel range in the A1:A2 or A1..A2 format.
|
|||
|
*/
|
|||
|
function _convert_range2d($range)
|
|||
|
{
|
|||
|
$class = 2; // as far as I know, this is magick.
|
|||
|
|
|||
|
// Split the range into 2 cell refs
|
|||
|
if(preg_match("/^([A-I]?[A-Z])(\d+)\:([A-I]?[A-Z])(\d+)$/",$range)) {
|
|||
|
list($cell1, $cell2) = split(':', $range);
|
|||
|
}
|
|||
|
elseif(preg_match("/^([A-I]?[A-Z])(\d+)\.\.([A-I]?[A-Z])(\d+)$/",$range)) {
|
|||
|
list($cell1, $cell2) = split('\.\.', $range);
|
|||
|
}
|
|||
|
else {
|
|||
|
die("Unknown range separator");
|
|||
|
}
|
|||
|
|
|||
|
// Convert the cell references
|
|||
|
list($row1, $col1) = $this->_cell_to_packed_rowcol($cell1);
|
|||
|
list($row2, $col2) = $this->_cell_to_packed_rowcol($cell2);
|
|||
|
|
|||
|
// The ptg value depends on the class of the ptg.
|
|||
|
if ($class == 0) {
|
|||
|
$ptgArea = pack("C", $this->ptg['ptgArea']);
|
|||
|
}
|
|||
|
elseif ($class == 1) {
|
|||
|
$ptgArea = pack("C", $this->ptg['ptgAreaV']);
|
|||
|
}
|
|||
|
elseif ($class == 2) {
|
|||
|
$ptgArea = pack("C", $this->ptg['ptgAreaA']);
|
|||
|
}
|
|||
|
else{
|
|||
|
die("Unknown class ");
|
|||
|
}
|
|||
|
|
|||
|
return($ptgArea . $row1 . $row2 . $col1. $col2);
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* Convert an Excel reference such as A1, $B2, C$3 or $D$4 to a ptgRefV.
|
|||
|
*
|
|||
|
* @param string $cell An Excel cell reference
|
|||
|
*/
|
|||
|
function _convert_ref2d($cell)
|
|||
|
{
|
|||
|
$class = 2; // as far as I know, this is magick.
|
|||
|
|
|||
|
// Convert the cell reference
|
|||
|
list($row, $col) = $this->_cell_to_packed_rowcol($cell);
|
|||
|
|
|||
|
// The ptg value depends on the class of the ptg.
|
|||
|
if ($class == 0) {
|
|||
|
$ptgRef = pack("C", $this->ptg['ptgRef']);
|
|||
|
}
|
|||
|
elseif ($class == 1) {
|
|||
|
$ptgRef = pack("C", $this->ptg['ptgRefV']);
|
|||
|
}
|
|||
|
elseif ($class == 2) {
|
|||
|
$ptgRef = pack("C", $this->ptg['ptgRefA']);
|
|||
|
}
|
|||
|
else{
|
|||
|
die("Unknown class ");
|
|||
|
}
|
|||
|
return $ptgRef.$row.$col;
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* pack() row and column into the required 3 byte format.
|
|||
|
*
|
|||
|
* @param string $cell The Excel cell reference to be packed
|
|||
|
*/
|
|||
|
function _cell_to_packed_rowcol($cell)
|
|||
|
{
|
|||
|
list($row, $col, $row_rel, $col_rel) = $this->_cell_to_rowcol($cell);
|
|||
|
if ($col >= 256) {
|
|||
|
die("Column in: $cell greater than 255 ");
|
|||
|
}
|
|||
|
if ($row >= 16384) {
|
|||
|
die("Row in: $cell greater than 16384 ");
|
|||
|
}
|
|||
|
|
|||
|
// Set the high bits to indicate if row or col are relative.
|
|||
|
$row |= $col_rel << 14;
|
|||
|
$row |= $row_rel << 15;
|
|||
|
|
|||
|
$row = pack('v', $row);
|
|||
|
$col = pack('C', $col);
|
|||
|
|
|||
|
return (array($row, $col));
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* Convert an Excel cell reference such as A1 or $B2 or C$3 or $D$4 to a zero
|
|||
|
* indexed row and column number. Also returns two boolean values to indicate
|
|||
|
* whether the row or column are relative references.
|
|||
|
*
|
|||
|
* @param string $cell The Excel cell reference in A1 format.
|
|||
|
*/
|
|||
|
function _cell_to_rowcol($cell)
|
|||
|
{
|
|||
|
preg_match('/(\$)?([A-I]?[A-Z])(\$)?(\d+)/',$cell,$match);
|
|||
|
// return absolute column if there is a $ in the ref
|
|||
|
$col_rel = empty($match[1]) ? 1 : 0;
|
|||
|
$col_ref = $match[2];
|
|||
|
$row_rel = empty($match[3]) ? 1 : 0;
|
|||
|
$row = $match[4];
|
|||
|
|
|||
|
// Convert base26 column string to a number.
|
|||
|
$expn = strlen($col_ref) - 1;
|
|||
|
$col = 0;
|
|||
|
for($i=0; $i < strlen($col_ref); $i++)
|
|||
|
{
|
|||
|
$col += (ord($col_ref{$i}) - ord('A') + 1) * pow(26, $expn);
|
|||
|
$expn--;
|
|||
|
}
|
|||
|
|
|||
|
// Convert 1-index to zero-index
|
|||
|
$row--;
|
|||
|
$col--;
|
|||
|
|
|||
|
return(array($row, $col, $row_rel, $col_rel));
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* Advance to the next valid token.
|
|||
|
*/
|
|||
|
function _advance()
|
|||
|
{
|
|||
|
$i = $this->_current_char;
|
|||
|
// eat up white spaces
|
|||
|
if($i < strlen($this->_formula))
|
|||
|
{
|
|||
|
while($this->_formula{$i} == " ")
|
|||
|
{
|
|||
|
$i++;
|
|||
|
}
|
|||
|
if($i < strlen($this->_formula) - 1)
|
|||
|
{
|
|||
|
$this->_lookahead = $this->_formula{$i+1};
|
|||
|
}
|
|||
|
$token = "";
|
|||
|
}
|
|||
|
while($i < strlen($this->_formula))
|
|||
|
{
|
|||
|
$token .= $this->_formula{$i};
|
|||
|
if($this->_match($token) != '')
|
|||
|
{
|
|||
|
if($i < strlen($this->_formula) - 1)
|
|||
|
{
|
|||
|
$this->_lookahead = $this->_formula{$i+1};
|
|||
|
}
|
|||
|
$this->_current_char = $i + 1;
|
|||
|
$this->_current_token = $token;
|
|||
|
return(1);
|
|||
|
}
|
|||
|
$this->_lookahead = $this->_formula{$i+2};
|
|||
|
$i++;
|
|||
|
}
|
|||
|
//die("Lexical error ".$this->_current_char);
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* Checks if it's a valid token.
|
|||
|
*
|
|||
|
* @param mixed $token The token to check.
|
|||
|
*/
|
|||
|
function _match($token)
|
|||
|
{
|
|||
|
switch($token)
|
|||
|
{
|
|||
|
case ADD:
|
|||
|
return($token);
|
|||
|
break;
|
|||
|
case SUB:
|
|||
|
return($token);
|
|||
|
break;
|
|||
|
case MUL:
|
|||
|
return($token);
|
|||
|
break;
|
|||
|
case DIV:
|
|||
|
return($token);
|
|||
|
break;
|
|||
|
case OPEN:
|
|||
|
return($token);
|
|||
|
break;
|
|||
|
case CLOSE:
|
|||
|
return($token);
|
|||
|
break;
|
|||
|
case COMA:
|
|||
|
return($token);
|
|||
|
break;
|
|||
|
default:
|
|||
|
// if it's a reference
|
|||
|
if(eregi("^[A-I]?[A-Z][0-9]+$",$token) and
|
|||
|
!ereg("[0-9]",$this->_lookahead) and
|
|||
|
($this->_lookahead != ':') and ($this->_lookahead != '.'))
|
|||
|
{
|
|||
|
return($token);
|
|||
|
}
|
|||
|
// if it's a range (A1:A2)
|
|||
|
elseif(eregi("^[A-I]?[A-Z][0-9]+:[A-I]?[A-Z][0-9]+$",$token) and
|
|||
|
!ereg("[0-9]",$this->_lookahead))
|
|||
|
{
|
|||
|
return($token);
|
|||
|
}
|
|||
|
// if it's a range (A1..A2)
|
|||
|
elseif(eregi("^[A-I]?[A-Z][0-9]+\.\.[A-I]?[A-Z][0-9]+$",$token) and
|
|||
|
!ereg("[0-9]",$this->_lookahead))
|
|||
|
{
|
|||
|
return($token);
|
|||
|
}
|
|||
|
elseif(is_numeric($token) and !is_numeric($token.$this->_lookahead))
|
|||
|
{
|
|||
|
return($token);
|
|||
|
}
|
|||
|
// if it's a function call
|
|||
|
elseif(eregi("^[A-Z0-9<>-<2D>\.]+$",$token) and ($this->_lookahead == "("))
|
|||
|
|
|||
|
{
|
|||
|
return($token);
|
|||
|
}
|
|||
|
return '';
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* The parsing method. It parses a formula.
|
|||
|
*
|
|||
|
* @access public
|
|||
|
* @param string $formula The formula to parse, without the initial equal sign (=).
|
|||
|
*/
|
|||
|
function parse($formula)
|
|||
|
{
|
|||
|
$this->_current_char = 0;
|
|||
|
$this->_formula = $formula;
|
|||
|
$this->_lookahead = $formula{1};
|
|||
|
$this->_advance();
|
|||
|
$this->_parse_tree = $this->_expression();
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* It parses a expression. It assumes the following rule:
|
|||
|
* Expr -> Term [("+" | "-") Term]
|
|||
|
*
|
|||
|
* @return mixed The parsed ptg'd tree
|
|||
|
*/
|
|||
|
function _expression()
|
|||
|
{
|
|||
|
$result = $this->_term();
|
|||
|
while ($this->_current_token == ADD or $this->_current_token == SUB)
|
|||
|
{
|
|||
|
if ($this->_current_token == ADD)
|
|||
|
{
|
|||
|
$this->_advance();
|
|||
|
$result = $this->_create_tree('ptgAdd', $result, $this->_term());
|
|||
|
}
|
|||
|
else
|
|||
|
{
|
|||
|
$this->_advance();
|
|||
|
$result = $this->_create_tree('ptgSub', $result, $this->_term());
|
|||
|
}
|
|||
|
}
|
|||
|
return $result;
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* This function just introduces a ptgParen element in the tree, so that Excel
|
|||
|
* doesn't get confused when working with a parenthesized formula afterwards.
|
|||
|
*
|
|||
|
* @see _fact
|
|||
|
* @return mixed The parsed ptg'd tree
|
|||
|
*/
|
|||
|
function _parenthesized_expression()
|
|||
|
{
|
|||
|
$result = $this->_create_tree('ptgParen', $this->_expression(), '');
|
|||
|
return($result);
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* It parses a term. It assumes the following rule:
|
|||
|
* Term -> Fact [("*" | "/") Fact]
|
|||
|
*
|
|||
|
* @return mixed The parsed ptg'd tree
|
|||
|
*/
|
|||
|
function _term()
|
|||
|
{
|
|||
|
$result = $this->_fact();
|
|||
|
while ($this->_current_token == MUL || $this->_current_token == DIV)
|
|||
|
{
|
|||
|
if ($this->_current_token == MUL)
|
|||
|
{
|
|||
|
$this->_advance();
|
|||
|
$result = $this->_create_tree('ptgMul', $result, $this->_fact());
|
|||
|
}
|
|||
|
else
|
|||
|
{
|
|||
|
$this->_advance();
|
|||
|
$result = $this->_create_tree('ptgDiv', $result, $this->_fact());
|
|||
|
}
|
|||
|
}
|
|||
|
return($result);
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* It parses a factor. It assumes the following rule:
|
|||
|
* Fact -> ( Expr )
|
|||
|
* | CellRef
|
|||
|
* | CellRange
|
|||
|
* | Number
|
|||
|
* | Function
|
|||
|
*
|
|||
|
* @return mixed The parsed ptg'd tree
|
|||
|
*/
|
|||
|
function _fact()
|
|||
|
{
|
|||
|
if ($this->_current_token == OPEN)
|
|||
|
{
|
|||
|
$this->_advance(); // eat the "("
|
|||
|
$result = $this->_parenthesized_expression();//$this->_expression();
|
|||
|
|
|||
|
if ($this->_current_token != CLOSE) {
|
|||
|
die("')' token expected.");
|
|||
|
}
|
|||
|
$this->_advance(); // eat the ")"
|
|||
|
return($result);
|
|||
|
}
|
|||
|
// if it's a reference
|
|||
|
if (eregi("^[A-I]?[A-Z][0-9]+$",$this->_current_token))
|
|||
|
{
|
|||
|
$result = $this->_create_tree($this->_current_token, '', '');
|
|||
|
$this->_advance();
|
|||
|
return($result);
|
|||
|
}
|
|||
|
// if it's a range
|
|||
|
elseif (eregi("^[A-I]?[A-Z][0-9]+:[A-I]?[A-Z][0-9]+$",$this->_current_token) or
|
|||
|
eregi("^[A-I]?[A-Z][0-9]+\.\.[A-I]?[A-Z][0-9]+$",$this->_current_token))
|
|||
|
{
|
|||
|
$result = $this->_current_token;
|
|||
|
$this->_advance();
|
|||
|
return($result);
|
|||
|
}
|
|||
|
elseif (is_numeric($this->_current_token))
|
|||
|
{
|
|||
|
$result = $this->_create_tree($this->_current_token, '', '');
|
|||
|
$this->_advance();
|
|||
|
return($result);
|
|||
|
}
|
|||
|
// if it's a function call
|
|||
|
elseif (eregi("^[A-Z0-9<>-<2D>\.]+$",$this->_current_token))
|
|||
|
{
|
|||
|
$result = $this->_func();
|
|||
|
return($result);
|
|||
|
}
|
|||
|
die("Sintactic error: ".$this->_current_token.", lookahead: ".
|
|||
|
$this->_lookahead.", current char: ".$this->_current_char);
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* It parses a function call. It assumes the following rule:
|
|||
|
* Func -> ( Expr [,Expr]* )
|
|||
|
*
|
|||
|
*/
|
|||
|
function _func()
|
|||
|
{
|
|||
|
$num_args = 0; // number of arguments received
|
|||
|
$function = $this->_current_token;
|
|||
|
$this->_advance();
|
|||
|
$this->_advance(); // eat the "("
|
|||
|
while($this->_current_token != ')')
|
|||
|
{
|
|||
|
if($num_args > 0)
|
|||
|
{
|
|||
|
if($this->_current_token == COMA) {
|
|||
|
$this->_advance(); // eat the ","
|
|||
|
}
|
|||
|
else {
|
|||
|
die("Sintactic error: coma expected $num_args");
|
|||
|
}
|
|||
|
$result = $this->_create_tree('arg', $result, $this->_expression());
|
|||
|
}
|
|||
|
else {
|
|||
|
$result = $this->_create_tree('arg', '', $this->_expression());
|
|||
|
}
|
|||
|
$num_args++;
|
|||
|
}
|
|||
|
$args = $this->_functions[$function][1];
|
|||
|
// If fixed number of args eg. TIME($i,$j,$k). Check that the number of args is valid.
|
|||
|
if (($args >= 0) and ($args != $num_args))
|
|||
|
{
|
|||
|
die("Incorrect number of arguments in function $function() ");
|
|||
|
}
|
|||
|
|
|||
|
$result = $this->_create_tree($function, $result, '');
|
|||
|
$this->_advance(); // eat the ")"
|
|||
|
return($result);
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* Creates a tree. In fact an array which may have one or two arrays (sub-trees)
|
|||
|
* as elements.
|
|||
|
*
|
|||
|
* @param mixed $value The value of this node.
|
|||
|
* @param mixed $left The left array (sub-tree) or a final node.
|
|||
|
* @param mixed $right The right array (sub-tree) or a final node.
|
|||
|
*/
|
|||
|
function _create_tree($value, $left, $right)
|
|||
|
{
|
|||
|
return array('value' => $value, 'left' => $left, 'right' => $right);
|
|||
|
}
|
|||
|
|
|||
|
/**
|
|||
|
* Builds a string containing the tree in reverse polish notation (What you
|
|||
|
* would use in a HP calculator stack).
|
|||
|
* The following tree:
|
|||
|
*
|
|||
|
* +
|
|||
|
* / \
|
|||
|
* 2 3
|
|||
|
*
|
|||
|
* produces: "23+"
|
|||
|
*
|
|||
|
* The following tree:
|
|||
|
*
|
|||
|
* +
|
|||
|
* / \
|
|||
|
* 3 *
|
|||
|
* / \
|
|||
|
* 6 A1
|
|||
|
*
|
|||
|
* produces: "36A1*+"
|
|||
|
*
|
|||
|
* In fact all operands, functions, references, etc... are written as ptg's
|
|||
|
*
|
|||
|
* @access public
|
|||
|
* @param array $tree The optional tree to convert.
|
|||
|
*/
|
|||
|
function to_reverse_polish($tree = array())
|
|||
|
{
|
|||
|
$polish = ""; // the string we are going to return
|
|||
|
if (empty($tree)) // If it's the first call use _parse_tree
|
|||
|
{
|
|||
|
$tree = $this->_parse_tree;
|
|||
|
}
|
|||
|
if (is_array($tree['left']))
|
|||
|
{
|
|||
|
$polish .= $this->to_reverse_polish($tree['left']);
|
|||
|
}
|
|||
|
elseif($tree['left'] != '') // It's a final node
|
|||
|
{
|
|||
|
$polish .= $this->_convert($tree['left']); //$tree['left'];
|
|||
|
}
|
|||
|
if (is_array($tree['right']))
|
|||
|
{
|
|||
|
$polish .= $this->to_reverse_polish($tree['right']);
|
|||
|
}
|
|||
|
elseif($tree['right'] != '') // It's a final node
|
|||
|
{
|
|||
|
$polish .= $this->_convert($tree['right']);
|
|||
|
}
|
|||
|
$polish .= $this->_convert($tree['value']);
|
|||
|
return $polish;
|
|||
|
}
|
|||
|
}
|
|||
|
?>
|