<?php

/**

 * PHPExcel

 *

 * Copyright (c) 2006 - 2014 PHPExcel

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

 *

 * @category   PHPExcel

 * @package    PHPExcel_Writer_Excel5

 * @copyright  Copyright (c) 2006 - 2014 PHPExcel (http://www.codeplex.com/PHPExcel)

 * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt	LGPL

 * @version    1.8.0, 2014-03-02

 */



// Original file header of PEAR::Spreadsheet_Excel_Writer_Parser (used as the base for this class):

// -----------------------------------------------------------------------------------------

// *  Class for parsing Excel formulas

// *

// *  License Information:

// *

// *    Spreadsheet_Excel_Writer:  A library for generating Excel Spreadsheets

// *    Copyright (c) 2002-2003 Xavier Noguer xnoguer@rezebra.com

// *

// *    This library is free software; you can redistribute it and/or

// *    modify it under the terms of the GNU Lesser General Public

// *    License as published by the Free Software Foundation; either

// *    version 2.1 of the License, or (at your option) any later version.

// *

// *    This library is distributed in the hope that it will be useful,

// *    but WITHOUT ANY WARRANTY; without even the implied warranty of

// *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

// *    Lesser General Public License for more details.

// *

// *    You should have received a copy of the GNU Lesser General Public

// *    License along with this library; if not, write to the Free Software

// *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

// */





/**

 * PHPExcel_Writer_Excel5_Parser

 *

 * @category   PHPExcel

 * @package    PHPExcel_Writer_Excel5

 * @copyright  Copyright (c) 2006 - 2014 PHPExcel (http://www.codeplex.com/PHPExcel)

 */

class PHPExcel_Writer_Excel5_Parser

{

	/**	Constants				*/

	// Sheet title in unquoted form

	// Invalid sheet title characters cannot occur in the sheet title:

	// 		*:/\?[]

	// Moreover, there are valid sheet title characters that cannot occur in unquoted form (there may be more?)

	// +-% '^&<>=,;#()"{}

	const REGEX_SHEET_TITLE_UNQUOTED = '[^\*\:\/\\\\\?\[\]\+\-\% \\\'\^\&\<\>\=\,\;\#\(\)\"\{\}]+';



	// Sheet title in quoted form (without surrounding quotes)

	// Invalid sheet title characters cannot occur in the sheet title:

	// *:/\?[]					(usual invalid sheet title characters)

	// Single quote is represented as a pair ''

	const REGEX_SHEET_TITLE_QUOTED = '(([^\*\:\/\\\\\?\[\]\\\'])+|(\\\'\\\')+)+';



	/**

	 * The index of the character we are currently looking at

	 * @var integer

	 */

	public $_current_char;



	/**

	 * The token we are working on.

	 * @var string

	 */

	public $_current_token;



	/**

	 * The formula to parse

	 * @var string

	 */

	public $_formula;



	/**

	 * The character ahead of the current char

	 * @var string

	 */

	public $_lookahead;



	/**

	 * The parse tree to be generated

	 * @var string

	 */

	public $_parse_tree;



	/**

	 * Array of external sheets

	 * @var array

	 */

	public $_ext_sheets;



	/**

	 * Array of sheet references in the form of REF structures

	 * @var array

	 */

	public $_references;



	/**

	 * The class constructor

	 *

	 */

	public function __construct()

	{

		$this->_current_char  = 0;

		$this->_current_token = '';       // The token we are working on.

		$this->_formula       = '';       // The formula to parse.

		$this->_lookahead     = '';       // The character ahead of the current char.

		$this->_parse_tree    = '';       // The parse tree to be generated.

		$this->_initializeHashes();      // Initialize the hashes: ptg's and function's ptg's

		$this->_ext_sheets = array();

		$this->_references = array();

	}



	/**

	 * Initialize the ptg and function hashes.

	 *

	 * @access private

	 */

	function _initializeHashes()

	{

		// The Excel ptg indices

		$this->ptg = array(

			'ptgExp'       => 0x01,

			'ptgTbl'       => 0x02,

			'ptgAdd'       => 0x03,

			'ptgSub'       => 0x04,

			'ptgMul'       => 0x05,

			'ptgDiv'       => 0x06,

			'ptgPower'     => 0x07,

			'ptgConcat'    => 0x08,

			'ptgLT'        => 0x09,

			'ptgLE'        => 0x0A,

			'ptgEQ'        => 0x0B,

			'ptgGE'        => 0x0C,

			'ptgGT'        => 0x0D,

			'ptgNE'        => 0x0E,

			'ptgIsect'     => 0x0F,

			'ptgUnion'     => 0x10,

			'ptgRange'     => 0x11,

			'ptgUplus'     => 0x12,

			'ptgUminus'    => 0x13,

			'ptgPercent'   => 0x14,

			'ptgParen'     => 0x15,

			'ptgMissArg'   => 0x16,

			'ptgStr'       => 0x17,

			'ptgAttr'      => 0x19,

			'ptgSheet'     => 0x1A,

			'ptgEndSheet'  => 0x1B,

			'ptgErr'       => 0x1C,

			'ptgBool'      => 0x1D,

			'ptgInt'       => 0x1E,

			'ptgNum'       => 0x1F,

			'ptgArray'     => 0x20,

			'ptgFunc'      => 0x21,

			'ptgFuncVar'   => 0x22,

			'ptgName'      => 0x23,

			'ptgRef'       => 0x24,

			'ptgArea'      => 0x25,

			'ptgMemArea'   => 0x26,

			'ptgMemErr'    => 0x27,

			'ptgMemNoMem'  => 0x28,

			'ptgMemFunc'   => 0x29,

			'ptgRefErr'    => 0x2A,

			'ptgAreaErr'   => 0x2B,

			'ptgRefN'      => 0x2C,

			'ptgAreaN'     => 0x2D,

			'ptgMemAreaN'  => 0x2E,

			'ptgMemNoMemN' => 0x2F,

			'ptgNameX'     => 0x39,

			'ptgRef3d'     => 0x3A,

			'ptgArea3d'    => 0x3B,

			'ptgRefErr3d'  => 0x3C,

			'ptgAreaErr3d' => 0x3D,

			'ptgArrayV'    => 0x40,

			'ptgFuncV'     => 0x41,

			'ptgFuncVarV'  => 0x42,

			'ptgNameV'     => 0x43,

			'ptgRefV'      => 0x44,

			'ptgAreaV'     => 0x45,

			'ptgMemAreaV'  => 0x46,

			'ptgMemErrV'   => 0x47,

			'ptgMemNoMemV' => 0x48,

			'ptgMemFuncV'  => 0x49,

			'ptgRefErrV'   => 0x4A,

			'ptgAreaErrV'  => 0x4B,

			'ptgRefNV'     => 0x4C,

			'ptgAreaNV'    => 0x4D,

			'ptgMemAreaNV' => 0x4E,

			'ptgMemNoMemN' => 0x4F,

			'ptgFuncCEV'   => 0x58,

			'ptgNameXV'    => 0x59,

			'ptgRef3dV'    => 0x5A,

			'ptgArea3dV'   => 0x5B,

			'ptgRefErr3dV' => 0x5C,

			'ptgAreaErr3d' => 0x5D,

			'ptgArrayA'    => 0x60,

			'ptgFuncA'     => 0x61,

			'ptgFuncVarA'  => 0x62,

			'ptgNameA'     => 0x63,

			'ptgRefA'      => 0x64,

			'ptgAreaA'     => 0x65,

			'ptgMemAreaA'  => 0x66,

			'ptgMemErrA'   => 0x67,

			'ptgMemNoMemA' => 0x68,

			'ptgMemFuncA'  => 0x69,

			'ptgRefErrA'   => 0x6A,

			'ptgAreaErrA'  => 0x6B,

			'ptgRefNA'     => 0x6C,

			'ptgAreaNA'    => 0x6D,

			'ptgMemAreaNA' => 0x6E,

			'ptgMemNoMemN' => 0x6F,

			'ptgFuncCEA'   => 0x78,

			'ptgNameXA'    => 0x79,

			'ptgRef3dA'    => 0x7A,

			'ptgArea3dA'   => 0x7B,

			'ptgRefErr3dA' => 0x7C,

			'ptgAreaErr3d' => 0x7D

			);



		// Thanks to Michael Meeks and Gnumeric for the initial arg values.

		//

		// The following hash was generated by "function_locale.pl" in the distro.

		// Refer to function_locale.pl for non-English function names.

		//

		// The array elements are as follow:

		// ptg:   The Excel function ptg code.

		// args:  The number of arguments that the function takes:

		//           >=0 is a fixed number of arguments.

		//           -1  is a variable  number of arguments.

		// class: The reference, value or array class of the function args.

		// vol:   The function is volatile.

		//

		$this->_functions = array(

			  // function                  ptg  args  class  vol

			  'COUNT'           => array(   0,   -1,    0,    0 ),

			  'IF'              => array(   1,   -1,    1,    0 ),

			  'ISNA'            => array(   2,    1,    1,    0 ),

			  'ISERROR'         => array(   3,    1,    1,    0 ),

			  'SUM'             => array(   4,   -1,    0,    0 ),

			  'AVERAGE'         => array(   5,   -1,    0,    0 ),

			  'MIN'             => array(   6,   -1,    0,    0 ),

			  'MAX'             => array(   7,   -1,    0,    0 ),

			  'ROW'             => array(   8,   -1,    0,    0 ),

			  'COLUMN'          => array(   9,   -1,    0,    0 ),

			  'NA'              => array(  10,    0,    0,    0 ),

			  'NPV'             => array(  11,   -1,    1,    0 ),

			  'STDEV'           => array(  12,   -1,    0,    0 ),

			  'DOLLAR'          => array(  13,   -1,    1,    0 ),

			  'FIXED'           => array(  14,   -1,    1,    0 ),

			  'SIN'             => array(  15,    1,    1,    0 ),

			  'COS'             => array(  16,    1,    1,    0 ),

			  'TAN'             => array(  17,    1,    1,    0 ),

			  'ATAN'            => array(  18,    1,    1,    0 ),

			  'PI'              => array(  19,    0,    1,    0 ),

			  'SQRT'            => array(  20,    1,    1,    0 ),

			  'EXP'             => array(  21,    1,    1,    0 ),

			  'LN'              => array(  22,    1,    1,    0 ),

			  'LOG10'           => array(  23,    1,    1,    0 ),

			  'ABS'             => array(  24,    1,    1,    0 ),

			  'INT'             => array(  25,    1,    1,    0 ),

			  'SIGN'            => array(  26,    1,    1,    0 ),

			  'ROUND'           => array(  27,    2,    1,    0 ),

			  'LOOKUP'          => array(  28,   -1,    0,    0 ),

			  'INDEX'           => array(  29,   -1,    0,    1 ),

			  'REPT'            => array(  30,    2,    1,    0 ),

			  'MID'             => array(  31,    3,    1,    0 ),

			  'LEN'             => array(  32,    1,    1,    0 ),

			  'VALUE'           => array(  33,    1,    1,    0 ),

			  'TRUE'            => array(  34,    0,    1,    0 ),

			  'FALSE'           => array(  35,    0,    1,    0 ),

			  'AND'             => array(  36,   -1,    0,    0 ),

			  'OR'              => array(  37,   -1,    0,    0 ),

			  'NOT'             => array(  38,    1,    1,    0 ),

			  'MOD'             => array(  39,    2,    1,    0 ),

			  'DCOUNT'          => array(  40,    3,    0,    0 ),

			  'DSUM'            => array(  41,    3,    0,    0 ),

			  'DAVERAGE'        => array(  42,    3,    0,    0 ),

			  'DMIN'            => array(  43,    3,    0,    0 ),

			  'DMAX'            => array(  44,    3,    0,    0 ),

			  'DSTDEV'          => array(  45,    3,    0,    0 ),

			  'VAR'             => array(  46,   -1,    0,    0 ),

			  'DVAR'            => array(  47,    3,    0,    0 ),

			  'TEXT'            => array(  48,    2,    1,    0 ),

			  'LINEST'          => array(  49,   -1,    0,    0 ),

			  'TREND'           => array(  50,   -1,    0,    0 ),

			  'LOGEST'          => array(  51,   -1,    0,    0 ),

			  'GROWTH'          => array(  52,   -1,    0,    0 ),

			  'PV'              => array(  56,   -1,    1,    0 ),

			  'FV'              => array(  57,   -1,    1,    0 ),

			  'NPER'            => array(  58,   -1,    1,    0 ),

			  'PMT'             => array(  59,   -1,    1,    0 ),

			  'RATE'            => array(  60,   -1,    1,    0 ),

			  'MIRR'            => array(  61,    3,    0,    0 ),

			  'IRR'             => array(  62,   -1,    0,    0 ),

			  'RAND'            => array(  63,    0,    1,    1 ),

			  'MATCH'           => array(  64,   -1,    0,    0 ),

			  'DATE'            => array(  65,    3,    1,    0 ),

			  'TIME'            => array(  66,    3,    1,    0 ),

			  'DAY'             => array(  67,    1,    1,    0 ),

			  'MONTH'           => array(  68,    1,    1,    0 ),

			  'YEAR'            => array(  69,    1,    1,    0 ),

			  'WEEKDAY'         => array(  70,   -1,    1,    0 ),

			  'HOUR'            => array(  71,    1,    1,    0 ),

			  'MINUTE'          => array(  72,    1,    1,    0 ),

			  'SECOND'          => array(  73,    1,    1,    0 ),

			  'NOW'             => array(  74,    0,    1,    1 ),

			  'AREAS'           => array(  75,    1,    0,    1 ),

			  'ROWS'            => array(  76,    1,    0,    1 ),

			  'COLUMNS'         => array(  77,    1,    0,    1 ),

			  'OFFSET'          => array(  78,   -1,    0,    1 ),

			  'SEARCH'          => array(  82,   -1,    1,    0 ),

			  'TRANSPOSE'       => array(  83,    1,    1,    0 ),

			  'TYPE'            => array(  86,    1,    1,    0 ),

			  'ATAN2'           => array(  97,    2,    1,    0 ),

			  'ASIN'            => array(  98,    1,    1,    0 ),

			  'ACOS'            => array(  99,    1,    1,    0 ),

			  'CHOOSE'          => array( 100,   -1,    1,    0 ),

			  'HLOOKUP'         => array( 101,   -1,    0,    0 ),

			  'VLOOKUP'         => array( 102,   -1,    0,    0 ),

			  'ISREF'           => array( 105,    1,    0,    0 ),

			  'LOG'             => array( 109,   -1,    1,    0 ),

			  'CHAR'            => array( 111,    1,    1,    0 ),

			  'LOWER'           => array( 112,    1,    1,    0 ),

			  'UPPER'           => array( 113,    1,    1,    0 ),

			  'PROPER'          => array( 114,    1,    1,    0 ),

			  'LEFT'            => array( 115,   -1,    1,    0 ),

			  'RIGHT'           => array( 116,   -1,    1,    0 ),

			  'EXACT'           => array( 117,    2,    1,    0 ),

			  'TRIM'            => array( 118,    1,    1,    0 ),

			  'REPLACE'         => array( 119,    4,    1,    0 ),

			  'SUBSTITUTE'      => array( 120,   -1,    1,    0 ),

			  'CODE'            => array( 121,    1,    1,    0 ),

			  'FIND'            => array( 124,   -1,    1,    0 ),

			  'CELL'            => array( 125,   -1,    0,    1 ),

			  'ISERR'           => array( 126,    1,    1,    0 ),

			  'ISTEXT'          => array( 127,    1,    1,    0 ),

			  'ISNUMBER'        => array( 128,    1,    1,    0 ),

			  'ISBLANK'         => array( 129,    1,    1,    0 ),

			  'T'               => array( 130,    1,    0,    0 ),

			  'N'               => array( 131,    1,    0,    0 ),

			  'DATEVALUE'       => array( 140,    1,    1,    0 ),

			  'TIMEVALUE'       => array( 141,    1,    1,    0 ),

			  'SLN'             => array( 142,    3,    1,    0 ),

			  'SYD'             => array( 143,    4,    1,    0 ),

			  'DDB'             => array( 144,   -1,    1,    0 ),

			  'INDIRECT'        => array( 148,   -1,    1,    1 ),

			  'CALL'            => array( 150,   -1,    1,    0 ),

			  'CLEAN'           => array( 162,    1,    1,    0 ),

			  'MDETERM'         => array( 163,    1,    2,    0 ),

			  'MINVERSE'        => array( 164,    1,    2,    0 ),

			  'MMULT'           => array( 165,    2,    2,    0 ),

			  'IPMT'            => array( 167,   -1,    1,    0 ),

			  'PPMT'            => array( 168,   -1,    1,    0 ),

			  'COUNTA'          => array( 169,   -1,    0,    0 ),

			  'PRODUCT'         => array( 183,   -1,    0,    0 ),

			  'FACT'            => array( 184,    1,    1,    0 ),

			  'DPRODUCT'        => array( 189,    3,    0,    0 ),

			  'ISNONTEXT'       => array( 190,    1,    1,    0 ),

			  'STDEVP'          => array( 193,   -1,    0,    0 ),

			  'VARP'            => array( 194,   -1,    0,    0 ),

			  'DSTDEVP'         => array( 195,    3,    0,    0 ),

			  'DVARP'           => array( 196,    3,    0,    0 ),

			  'TRUNC'           => array( 197,   -1,    1,    0 ),

			  'ISLOGICAL'       => array( 198,    1,    1,    0 ),

			  'DCOUNTA'         => array( 199,    3,    0,    0 ),

			  'USDOLLAR'        => array( 204,   -1,    1,    0 ),

			  'FINDB'           => array( 205,   -1,    1,    0 ),

			  'SEARCHB'         => array( 206,   -1,    1,    0 ),

			  'REPLACEB'        => array( 207,    4,    1,    0 ),

			  'LEFTB'           => array( 208,   -1,    1,    0 ),

			  'RIGHTB'          => array( 209,   -1,    1,    0 ),

			  'MIDB'            => array( 210,    3,    1,    0 ),

			  'LENB'            => array( 211,    1,    1,    0 ),

			  'ROUNDUP'         => array( 212,    2,    1,    0 ),

			  'ROUNDDOWN'       => array( 213,    2,    1,    0 ),

			  'ASC'             => array( 214,    1,    1,    0 ),

			  'DBCS'            => array( 215,    1,    1,    0 ),

			  'RANK'            => array( 216,   -1,    0,    0 ),

			  'ADDRESS'         => array( 219,   -1,    1,    0 ),

			  'DAYS360'         => array( 220,   -1,    1,    0 ),

			  '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 ),

			  'ISPMT'           => array( 350,    4,    1,    0 ),

			  'DATEDIF'         => array( 351,    3,    1,    0 ),

			  'DATESTRING'      => array( 352,    1,    1,    0 ),

			  'NUMBERSTRING'    => array( 353,    2,    1,    0 ),

			  'ROMAN'           => array( 354,   -1,    1,    0 ),

			  'GETPIVOTDATA'    => array( 358,   -1,    0,    0 ),

			  'HYPERLINK'       => array( 359,   -1,    1,    0 ),

			  'PHONETIC'        => array( 360,    1,    0,    0 ),

			  'AVERAGEA'        => array( 361,   -1,    0,    0 ),

			  'MAXA'            => array( 362,   -1,    0,    0 ),

			  'MINA'            => array( 363,   -1,    0,    0 ),

			  'STDEVPA'         => array( 364,   -1,    0,    0 ),

			  'VARPA'           => array( 365,   -1,    0,    0 ),

			  'STDEVA'          => array( 366,   -1,    0,    0 ),

			  'VARA'            => array( 367,   -1,    0,    0 ),

			  'BAHTTEXT'        => array( 368,    1,    0,    0 ),

			  );

	}



	/**

	 * Convert a token to the proper ptg value.

	 *

	 * @access private

	 * @param mixed $token The token to convert.

	 * @return mixed the converted token on success

	 */

	function _convert($token)

	{

		if (preg_match("/\"([^\"]|\"\"){0,255}\"/", $token)) {

			return $this->_convertString($token);



		} elseif (is_numeric($token)) {

			return $this->_convertNumber($token);



		// match references like A1 or $A$1

		} elseif (preg_match('/^\$?([A-Ia-i]?[A-Za-z])\$?(\d+)$/',$token)) {

			return $this->_convertRef2d($token);



		// match external references like Sheet1!A1 or Sheet1:Sheet2!A1 or Sheet1!$A$1 or Sheet1:Sheet2!$A$1

		} elseif (preg_match("/^" . self::REGEX_SHEET_TITLE_UNQUOTED . "(\:" . self::REGEX_SHEET_TITLE_UNQUOTED . ")?\!\\$?[A-Ia-i]?[A-Za-z]\\$?(\d+)$/u",$token)) {

			return $this->_convertRef3d($token);



		// match external references like 'Sheet1'!A1 or 'Sheet1:Sheet2'!A1 or 'Sheet1'!$A$1 or 'Sheet1:Sheet2'!$A$1

		} elseif (preg_match("/^'" . self::REGEX_SHEET_TITLE_QUOTED . "(\:" . self::REGEX_SHEET_TITLE_QUOTED . ")?'\!\\$?[A-Ia-i]?[A-Za-z]\\$?(\d+)$/u",$token)) {

			return $this->_convertRef3d($token);



		// match ranges like A1:B2 or $A$1:$B$2

		} elseif (preg_match('/^(\$)?[A-Ia-i]?[A-Za-z](\$)?(\d+)\:(\$)?[A-Ia-i]?[A-Za-z](\$)?(\d+)$/', $token)) {

			return $this->_convertRange2d($token);



		// match external ranges like Sheet1!A1:B2 or Sheet1:Sheet2!A1:B2 or Sheet1!$A$1:$B$2 or Sheet1:Sheet2!$A$1:$B$2

		} elseif (preg_match("/^" . self::REGEX_SHEET_TITLE_UNQUOTED . "(\:" . self::REGEX_SHEET_TITLE_UNQUOTED . ")?\!\\$?([A-Ia-i]?[A-Za-z])?\\$?(\d+)\:\\$?([A-Ia-i]?[A-Za-z])?\\$?(\d+)$/u",$token)) {

			return $this->_convertRange3d($token);



		// match external ranges like 'Sheet1'!A1:B2 or 'Sheet1:Sheet2'!A1:B2 or 'Sheet1'!$A$1:$B$2 or 'Sheet1:Sheet2'!$A$1:$B$2

		} elseif (preg_match("/^'" . self::REGEX_SHEET_TITLE_QUOTED . "(\:" . self::REGEX_SHEET_TITLE_QUOTED . ")?'\!\\$?([A-Ia-i]?[A-Za-z])?\\$?(\d+)\:\\$?([A-Ia-i]?[A-Za-z])?\\$?(\d+)$/u",$token)) {

			return $this->_convertRange3d($token);



		// operators (including parentheses)

		} elseif (isset($this->ptg[$token])) {

			return pack("C", $this->ptg[$token]);



        // match error codes

		} elseif (preg_match("/^#[A-Z0\/]{3,5}[!?]{1}$/", $token) or $token == '#N/A') {

		    return $this->_convertError($token);



		// commented so argument number can be processed correctly. See toReversePolish().

		/*elseif (preg_match("/[A-Z0-9\xc0-\xdc\.]+/",$token))

		{

			return($this->_convertFunction($token,$this->_func_args));

		}*/



		// if it's an argument, ignore the token (the argument remains)

		} elseif ($token == 'arg') {

			return '';

		}



		// TODO: use real error codes

		throw new PHPExcel_Writer_Exception("Unknown token $token");

	}



	/**

	 * Convert a number token to ptgInt or ptgNum

	 *

	 * @access private

	 * @param mixed $num an integer or double for conversion to its ptg value

	 */

	function _convertNumber($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 (PHPExcel_Writer_Excel5_BIFFwriter::getByteOrder()) { // if it's Big Endian

				$num = strrev($num);

			}

			return pack("Cd", $this->ptg['ptgNum'], $num);

		}

	}



	/**

	 * Convert a string token to ptgStr

	 *

	 * @access private

	 * @param string $string A string for conversion to its ptg value.

	 * @return mixed the converted token on success

	 */

	function _convertString($string)

	{

		// chop away beggining and ending quotes

		$string = substr($string, 1, strlen($string) - 2);

		if (strlen($string) > 255) {

			throw new PHPExcel_Writer_Exception("String is too long");

		}



		return pack('C', $this->ptg['ptgStr']) . PHPExcel_Shared_String::UTF8toBIFF8UnicodeShort($string);

	}



	/**

	 * Convert a function to a ptgFunc or ptgFuncVarV depending on the number of

	 * args that it takes.

	 *

	 * @access private

	 * @param string  $token    The name of the function for convertion to ptg value.

	 * @param integer $num_args The number of arguments the function receives.

	 * @return string The packed ptg for the function

	 */

	function _convertFunction($token, $num_args)

	{

		$args     = $this->_functions[$token][1];

//		$volatile = $this->_functions[$token][3];



		// 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.

	 *

	 * @access private

	 * @param string	$range	An Excel range in the A1:A2

	 * @param int		$class

	 */

	function _convertRange2d($range, $class=0)

	{



		// TODO: possible class value 0,1,2 check Formula.pm

		// Split the range into 2 cell refs

		if (preg_match('/^(\$)?([A-Ia-i]?[A-Za-z])(\$)?(\d+)\:(\$)?([A-Ia-i]?[A-Za-z])(\$)?(\d+)$/', $range)) {

			list($cell1, $cell2) = explode(':', $range);

		} else {

			// TODO: use real error codes

			throw new PHPExcel_Writer_Exception("Unknown range separator");

		}



		// Convert the cell references

		list($row1, $col1) = $this->_cellToPackedRowcol($cell1);

		list($row2, $col2) = $this->_cellToPackedRowcol($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 {

			// TODO: use real error codes

			throw new PHPExcel_Writer_Exception("Unknown class $class");

		}

		return $ptgArea . $row1 . $row2 . $col1. $col2;

	}



	/**

	 * Convert an Excel 3d range such as "Sheet1!A1:D4" or "Sheet1:Sheet2!A1:D4" to

	 * a ptgArea3d.

	 *

	 * @access private

	 * @param string $token An Excel range in the Sheet1!A1:A2 format.

	 * @return mixed The packed ptgArea3d token on success.

	 */

	function _convertRange3d($token)

	{

//		$class = 0; // formulas like Sheet1!$A$1:$A$2 in list type data validation need this class (0x3B)



		// Split the ref at the ! symbol

		list($ext_ref, $range) = explode('!', $token);



		// Convert the external reference part (different for BIFF8)

		$ext_ref = $this->_getRefIndex($ext_ref);



		// Split the range into 2 cell refs

		list($cell1, $cell2) = explode(':', $range);



		// Convert the cell references

		if (preg_match("/^(\\$)?[A-Ia-i]?[A-Za-z](\\$)?(\d+)$/", $cell1)) {

			list($row1, $col1) = $this->_cellToPackedRowcol($cell1);

			list($row2, $col2) = $this->_cellToPackedRowcol($cell2);

		} else { // It's a rows range (like 26:27)

			 list($row1, $col1, $row2, $col2) = $this->_rangeToPackedRange($cell1.':'.$cell2);

		}



		// The ptg value depends on the class of the ptg.

//		if ($class == 0) {

			$ptgArea = pack("C", $this->ptg['ptgArea3d']);

//		} elseif ($class == 1) {

//			$ptgArea = pack("C", $this->ptg['ptgArea3dV']);

//		} elseif ($class == 2) {

//			$ptgArea = pack("C", $this->ptg['ptgArea3dA']);

//		} else {

//			throw new PHPExcel_Writer_Exception("Unknown class $class");

//		}



		return $ptgArea . $ext_ref . $row1 . $row2 . $col1. $col2;

	}



	/**

	 * Convert an Excel reference such as A1, $B2, C$3 or $D$4 to a ptgRefV.

	 *

	 * @access private

	 * @param string $cell An Excel cell reference

	 * @return string The cell in packed() format with the corresponding ptg

	 */

	function _convertRef2d($cell)

	{

//		$class = 2; // as far as I know, this is magick.



		// Convert the cell reference

		$cell_array = $this->_cellToPackedRowcol($cell);

		list($row, $col) = $cell_array;



		// 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 {

//			// TODO: use real error codes

//			throw new PHPExcel_Writer_Exception("Unknown class $class");

//		}

		return $ptgRef.$row.$col;

	}



	/**

	 * Convert an Excel 3d reference such as "Sheet1!A1" or "Sheet1:Sheet2!A1" to a

	 * ptgRef3d.

	 *

	 * @access private

	 * @param string $cell An Excel cell reference

	 * @return mixed The packed ptgRef3d token on success.

	 */

	function _convertRef3d($cell)

	{

//		$class = 2; // as far as I know, this is magick.



		// Split the ref at the ! symbol

		list($ext_ref, $cell) = explode('!', $cell);



		// Convert the external reference part (different for BIFF8)

		$ext_ref = $this->_getRefIndex($ext_ref);



		// Convert the cell reference part

		list($row, $col) = $this->_cellToPackedRowcol($cell);



		// The ptg value depends on the class of the ptg.

//		if ($class == 0) {

//			$ptgRef = pack("C", $this->ptg['ptgRef3d']);

//		} elseif ($class == 1) {

//			$ptgRef = pack("C", $this->ptg['ptgRef3dV']);

//		} elseif ($class == 2) {

			$ptgRef = pack("C", $this->ptg['ptgRef3dA']);

//		} else {

//			throw new PHPExcel_Writer_Exception("Unknown class $class");

//		}



		return $ptgRef . $ext_ref. $row . $col;

	}



    /**

     * Convert an error code to a ptgErr

     *

     * @access	private

	 * @param	string	$errorCode	The error code for conversion to its ptg value

     * @return	string				The error code ptgErr

     */

    function _convertError($errorCode)

    {

		switch ($errorCode) {

			case '#NULL!':	return pack("C", 0x00);

			case '#DIV/0!':	return pack("C", 0x07);

			case '#VALUE!':	return pack("C", 0x0F);

			case '#REF!':	return pack("C", 0x17);

			case '#NAME?':	return pack("C", 0x1D);

			case '#NUM!':	return pack("C", 0x24);

			case '#N/A':	return pack("C", 0x2A);

		}

		return pack("C", 0xFF);

    }



	/**

	 * Convert the sheet name part of an external reference, for example "Sheet1" or

	 * "Sheet1:Sheet2", to a packed structure.

	 *

	 * @access	private

	 * @param	string	$ext_ref	The name of the external reference

	 * @return	string				The reference index in packed() format

	 */

	function _packExtRef($ext_ref)

	{

		$ext_ref = preg_replace("/^'/", '', $ext_ref); // Remove leading  ' if any.

		$ext_ref = preg_replace("/'$/", '', $ext_ref); // Remove trailing ' if any.



		// Check if there is a sheet range eg., Sheet1:Sheet2.

		if (preg_match("/:/", $ext_ref)) {

			list($sheet_name1, $sheet_name2) = explode(':', $ext_ref);



			$sheet1 = $this->_getSheetIndex($sheet_name1);

			if ($sheet1 == -1) {

				throw new PHPExcel_Writer_Exception("Unknown sheet name $sheet_name1 in formula");

			}

			$sheet2 = $this->_getSheetIndex($sheet_name2);

			if ($sheet2 == -1) {

				throw new PHPExcel_Writer_Exception("Unknown sheet name $sheet_name2 in formula");

			}



			// Reverse max and min sheet numbers if necessary

			if ($sheet1 > $sheet2) {

				list($sheet1, $sheet2) = array($sheet2, $sheet1);

			}

		} else { // Single sheet name only.

			$sheet1 = $this->_getSheetIndex($ext_ref);

			if ($sheet1 == -1) {

				throw new PHPExcel_Writer_Exception("Unknown sheet name $ext_ref in formula");

			}

			$sheet2 = $sheet1;

		}



		// References are stored relative to 0xFFFF.

		$offset = -1 - $sheet1;



		return pack('vdvv', $offset, 0x00, $sheet1, $sheet2);

	}



	/**

	 * Look up the REF index that corresponds to an external sheet name

	 * (or range). If it doesn't exist yet add it to the workbook's references

	 * array. It assumes all sheet names given must exist.

	 *

	 * @access private

	 * @param string $ext_ref The name of the external reference

	 * @return mixed The reference index in packed() format on success

	 */

	function _getRefIndex($ext_ref)

	{

		$ext_ref = preg_replace("/^'/", '', $ext_ref); // Remove leading  ' if any.

		$ext_ref = preg_replace("/'$/", '', $ext_ref); // Remove trailing ' if any.

		$ext_ref = str_replace('\'\'', '\'', $ext_ref); // Replace escaped '' with '



		// Check if there is a sheet range eg., Sheet1:Sheet2.

		if (preg_match("/:/", $ext_ref)) {

			list($sheet_name1, $sheet_name2) = explode(':', $ext_ref);



			$sheet1 = $this->_getSheetIndex($sheet_name1);

			if ($sheet1 == -1) {

				throw new PHPExcel_Writer_Exception("Unknown sheet name $sheet_name1 in formula");

			}

			$sheet2 = $this->_getSheetIndex($sheet_name2);

			if ($sheet2 == -1) {

				throw new PHPExcel_Writer_Exception("Unknown sheet name $sheet_name2 in formula");

			}



			// Reverse max and min sheet numbers if necessary

			if ($sheet1 > $sheet2) {

				list($sheet1, $sheet2) = array($sheet2, $sheet1);

			}

		} else { // Single sheet name only.

			$sheet1 = $this->_getSheetIndex($ext_ref);

			if ($sheet1 == -1) {

				throw new PHPExcel_Writer_Exception("Unknown sheet name $ext_ref in formula");

			}

			$sheet2 = $sheet1;

		}



		// assume all references belong to this document

		$supbook_index = 0x00;

		$ref = pack('vvv', $supbook_index, $sheet1, $sheet2);

		$total_references = count($this->_references);

		$index = -1;

		for ($i = 0; $i < $total_references; ++$i) {

			if ($ref == $this->_references[$i]) {

				$index = $i;

				break;

			}

		}

		// if REF was not found add it to references array

		if ($index == -1) {

			$this->_references[$total_references] = $ref;

			$index = $total_references;

		}



		return pack('v', $index);

	}



	/**

	 * Look up the index that corresponds to an external sheet name. The hash of

	 * sheet names is updated by the addworksheet() method of the

	 * PHPExcel_Writer_Excel5_Workbook class.

	 *

	 * @access	private

	 * @param	string	$sheet_name		Sheet name

	 * @return	integer					The sheet index, -1 if the sheet was not found

	 */

	function _getSheetIndex($sheet_name)

	{

		if (!isset($this->_ext_sheets[$sheet_name])) {

			return -1;

		} else {

			return $this->_ext_sheets[$sheet_name];

		}

	}



	/**

	 * This method is used to update the array of sheet names. It is

	 * called by the addWorksheet() method of the

	 * PHPExcel_Writer_Excel5_Workbook class.

	 *

	 * @access public

	 * @see PHPExcel_Writer_Excel5_Workbook::addWorksheet()

	 * @param string  $name  The name of the worksheet being added

	 * @param integer $index The index of the worksheet being added

	 */

	function setExtSheet($name, $index)

	{

		$this->_ext_sheets[$name] = $index;

	}



	/**

	 * pack() row and column into the required 3 or 4 byte format.

	 *

	 * @access private

	 * @param string $cell The Excel cell reference to be packed

	 * @return array Array containing the row and column in packed() format

	 */

	function _cellToPackedRowcol($cell)

	{

		$cell = strtoupper($cell);

		list($row, $col, $row_rel, $col_rel) = $this->_cellToRowcol($cell);

		if ($col >= 256) {

			throw new PHPExcel_Writer_Exception("Column in: $cell greater than 255");

		}

		if ($row >= 65536) {

			throw new PHPExcel_Writer_Exception("Row in: $cell greater than 65536 ");

		}



		// Set the high bits to indicate if row or col are relative.

		$col |= $col_rel << 14;

		$col |= $row_rel << 15;

		$col = pack('v', $col);



		$row = pack('v', $row);



		return array($row, $col);

	}



	/**

	 * pack() row range into the required 3 or 4 byte format.

	 * Just using maximum col/rows, which is probably not the correct solution

	 *

	 * @access private

	 * @param string $range The Excel range to be packed

	 * @return array Array containing (row1,col1,row2,col2) in packed() format

	 */

	function _rangeToPackedRange($range)

	{

		preg_match('/(\$)?(\d+)\:(\$)?(\d+)/', $range, $match);

		// return absolute rows if there is a $ in the ref

		$row1_rel = empty($match[1]) ? 1 : 0;

		$row1     = $match[2];

		$row2_rel = empty($match[3]) ? 1 : 0;

		$row2     = $match[4];

		// Convert 1-index to zero-index

		--$row1;

		--$row2;

		// Trick poor inocent Excel

		$col1 = 0;

		$col2 = 65535; // FIXME: maximum possible value for Excel 5 (change this!!!)



		// FIXME: this changes for BIFF8

		if (($row1 >= 65536) or ($row2 >= 65536)) {

			throw new PHPExcel_Writer_Exception("Row in: $range greater than 65536 ");

		}



		// Set the high bits to indicate if rows are relative.

		$col1 |= $row1_rel << 15;

		$col2 |= $row2_rel << 15;

		$col1 = pack('v', $col1);

		$col2 = pack('v', $col2);



		$row1 = pack('v', $row1);

		$row2 = pack('v', $row2);



		return array($row1, $col1, $row2, $col2);

	}



	/**

	 * 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 (0,1) values to indicate

	 * whether the row or column are relative references.

	 *

	 * @access private

	 * @param string $cell The Excel cell reference in A1 format.

	 * @return array

	 */

	function _cellToRowcol($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;

		$col_ref_length = strlen($col_ref);

		for ($i = 0; $i < $col_ref_length; ++$i) {

			$col += (ord($col_ref{$i}) - 64) * 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.

	 *

	 * @access private

	 */

	function _advance()

	{

		$i = $this->_current_char;

		$formula_length = strlen($this->_formula);

		// eat up white spaces

		if ($i < $formula_length) {

			while ($this->_formula{$i} == " ") {

				++$i;

			}



			if ($i < ($formula_length - 1)) {

				$this->_lookahead = $this->_formula{$i+1};

			}

			$token = '';

		}



		while ($i < $formula_length) {

			$token .= $this->_formula{$i};



			if ($i < ($formula_length - 1)) {

				$this->_lookahead = $this->_formula{$i+1};

			} else {

				$this->_lookahead = '';

			}



			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;

			}



			if ($i < ($formula_length - 2)) {

				$this->_lookahead = $this->_formula{$i+2};

			} else { // if we run out of characters _lookahead becomes empty

				$this->_lookahead = '';

			}

			++$i;

		}

		//die("Lexical error ".$this->_current_char);

	}



	/**

	 * Checks if it's a valid token.

	 *

	 * @access private

	 * @param mixed $token The token to check.

	 * @return mixed       The checked token or false on failure

	 */

	function _match($token)

	{

		switch($token) {

			case "+":

			case "-":

			case "*":

			case "/":

			case "(":

			case ")":

			case ",":

			case ";":

			case ">=":

			case "<=":

			case "=":

			case "<>":

			case "^":

			case "&":

			case "%":

				return $token;

				break;

			case ">":

				if ($this->_lookahead == '=') { // it's a GE token

					break;

				}

				return $token;

				break;

			case "<":

				// it's a LE or a NE token

				if (($this->_lookahead == '=') or ($this->_lookahead == '>')) {

					break;

				}

				return $token;

				break;

			default:

				// if it's a reference A1 or $A$1 or $A1 or A$1

				if (preg_match('/^\$?[A-Ia-i]?[A-Za-z]\$?[0-9]+$/',$token) and

				   !preg_match("/[0-9]/",$this->_lookahead) and

				   ($this->_lookahead != ':') and ($this->_lookahead != '.') and

				   ($this->_lookahead != '!'))

				{

					return $token;

				}

				// If it's an external reference (Sheet1!A1 or Sheet1:Sheet2!A1 or Sheet1!$A$1 or Sheet1:Sheet2!$A$1)

				elseif (preg_match("/^" . self::REGEX_SHEET_TITLE_UNQUOTED . "(\:" . self::REGEX_SHEET_TITLE_UNQUOTED . ")?\!\\$?[A-Ia-i]?[A-Za-z]\\$?[0-9]+$/u",$token) and

					   !preg_match("/[0-9]/",$this->_lookahead) and

					   ($this->_lookahead != ':') and ($this->_lookahead != '.'))

				{

					return $token;

				}

				// If it's an external reference ('Sheet1'!A1 or 'Sheet1:Sheet2'!A1 or 'Sheet1'!$A$1 or 'Sheet1:Sheet2'!$A$1)

				elseif (preg_match("/^'" . self::REGEX_SHEET_TITLE_QUOTED . "(\:" . self::REGEX_SHEET_TITLE_QUOTED . ")?'\!\\$?[A-Ia-i]?[A-Za-z]\\$?[0-9]+$/u",$token) and

					   !preg_match("/[0-9]/",$this->_lookahead) and

					   ($this->_lookahead != ':') and ($this->_lookahead != '.'))

				{

					return $token;

				}

				// if it's a range A1:A2 or $A$1:$A$2

				elseif (preg_match('/^(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+:(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+$/', $token) and

					   !preg_match("/[0-9]/",$this->_lookahead))

				{

					return $token;

				}

				// If it's an external range like Sheet1!A1:B2 or Sheet1:Sheet2!A1:B2 or Sheet1!$A$1:$B$2 or Sheet1:Sheet2!$A$1:$B$2

				elseif (preg_match("/^" . self::REGEX_SHEET_TITLE_UNQUOTED . "(\:" . self::REGEX_SHEET_TITLE_UNQUOTED . ")?\!\\$?([A-Ia-i]?[A-Za-z])?\\$?[0-9]+:\\$?([A-Ia-i]?[A-Za-z])?\\$?[0-9]+$/u",$token) and

					   !preg_match("/[0-9]/",$this->_lookahead))

				{

					return $token;

				}

				// If it's an external range like 'Sheet1'!A1:B2 or 'Sheet1:Sheet2'!A1:B2 or 'Sheet1'!$A$1:$B$2 or 'Sheet1:Sheet2'!$A$1:$B$2

				elseif (preg_match("/^'" . self::REGEX_SHEET_TITLE_QUOTED . "(\:" . self::REGEX_SHEET_TITLE_QUOTED . ")?'\!\\$?([A-Ia-i]?[A-Za-z])?\\$?[0-9]+:\\$?([A-Ia-i]?[A-Za-z])?\\$?[0-9]+$/u",$token) and

					   !preg_match("/[0-9]/",$this->_lookahead))

				{

					return $token;

				}

				// If it's a number (check that it's not a sheet name or range)

				elseif (is_numeric($token) and

						(!is_numeric($token.$this->_lookahead) or ($this->_lookahead == '')) and

						($this->_lookahead != '!') and ($this->_lookahead != ':'))

				{

					return $token;

				}

				// If it's a string (of maximum 255 characters)

				elseif (preg_match("/\"([^\"]|\"\"){0,255}\"/",$token) and $this->_lookahead != '"' and (substr_count($token, '"')%2 == 0))

				{

					return $token;

				}

			    // If it's an error code

			    elseif (preg_match("/^#[A-Z0\/]{3,5}[!?]{1}$/", $token) or $token == '#N/A')

			    {

			        return $token;

			    }

				// if it's a function call

				elseif (preg_match("/^[A-Z0-9\xc0-\xdc\.]+$/i",$token) and ($this->_lookahead == "("))

				{

					return $token;

				}

				//	It's an argument of some description (e.g. a named range),

				//		precise nature yet to be determined

				elseif(substr($token,-1) == ')') {

					return $token;

				}

				return '';

		}

	}



	/**

	 * The parsing method. It parses a formula.

	 *

	 * @access public

	 * @param string $formula The formula to parse, without the initial equal

	 *                        sign (=).

	 * @return mixed true on success

	 */

	function parse($formula)

	{

		$this->_current_char = 0;

		$this->_formula      = $formula;

		$this->_lookahead    = isset($formula{1}) ? $formula{1} : '';

		$this->_advance();

		$this->_parse_tree   = $this->_condition();

		return true;

	}



	/**

	 * It parses a condition. It assumes the following rule:

	 * Cond -> Expr [(">" | "<") Expr]

	 *

	 * @access private

	 * @return mixed The parsed ptg'd tree on success

	 */

	function _condition()

	{

		$result = $this->_expression();

		if ($this->_current_token == "<") {

			$this->_advance();

			$result2 = $this->_expression();

			$result = $this->_createTree('ptgLT', $result, $result2);

		} elseif ($this->_current_token == ">") {

			$this->_advance();

			$result2 = $this->_expression();

			$result = $this->_createTree('ptgGT', $result, $result2);

		} elseif ($this->_current_token == "<=") {

			$this->_advance();

			$result2 = $this->_expression();

			$result = $this->_createTree('ptgLE', $result, $result2);

		} elseif ($this->_current_token == ">=") {

			$this->_advance();

			$result2 = $this->_expression();

			$result = $this->_createTree('ptgGE', $result, $result2);

		} elseif ($this->_current_token == "=") {

			$this->_advance();

			$result2 = $this->_expression();

			$result = $this->_createTree('ptgEQ', $result, $result2);

		} elseif ($this->_current_token == "<>") {

			$this->_advance();

			$result2 = $this->_expression();

			$result = $this->_createTree('ptgNE', $result, $result2);

		} elseif ($this->_current_token == "&") {

		    $this->_advance();

		    $result2 = $this->_expression();

		    $result = $this->_createTree('ptgConcat', $result, $result2);

		}

		return $result;

	}



	/**

	 * It parses a expression. It assumes the following rule:

	 * Expr -> Term [("+" | "-") Term]

	 *      -> "string"

	 *      -> "-" Term : Negative value

	 *      -> "+" Term : Positive value

	 *      -> Error code

	 *

	 * @access private

	 * @return mixed The parsed ptg'd tree on success

	 */

	function _expression()

	{

		// If it's a string return a string node

		if (preg_match("/\"([^\"]|\"\"){0,255}\"/", $this->_current_token)) {

			$tmp = str_replace('""', '"', $this->_current_token);

			if (($tmp == '"') || ($tmp == '')) $tmp = '""';	//	Trap for "" that has been used for an empty string

			$result = $this->_createTree($tmp, '', '');

			$this->_advance();

			return $result;

        // If it's an error code

        } elseif (preg_match("/^#[A-Z0\/]{3,5}[!?]{1}$/", $this->_current_token) or $this->_current_token == '#N/A'){

		    $result = $this->_createTree($this->_current_token, 'ptgErr', '');

		    $this->_advance();

		    return $result;

		// If it's a negative value

        } elseif ($this->_current_token == "-") {

			// catch "-" Term

			$this->_advance();

			$result2 = $this->_expression();

			$result = $this->_createTree('ptgUminus', $result2, '');

			return $result;

        // If it's a positive value

		} elseif ($this->_current_token == "+") {

			// catch "+" Term

			$this->_advance();

			$result2 = $this->_expression();

			$result = $this->_createTree('ptgUplus', $result2, '');

			return $result;

		}

		$result = $this->_term();

		while (($this->_current_token == "+") or

			   ($this->_current_token == "-") or

			   ($this->_current_token == "^")) {

		/**/

			if ($this->_current_token == "+") {

				$this->_advance();

				$result2 = $this->_term();

				$result = $this->_createTree('ptgAdd', $result, $result2);

			} elseif ($this->_current_token == "-") {

				$this->_advance();

				$result2 = $this->_term();

				$result = $this->_createTree('ptgSub', $result, $result2);

			} else {

				$this->_advance();

				$result2 = $this->_term();

				$result = $this->_createTree('ptgPower', $result, $result2);

			}

		}

		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.

	 *

	 * @access private

	 * @see _fact()

	 * @return array The parsed ptg'd tree

	 */

	function _parenthesizedExpression()

	{

		$result = $this->_createTree('ptgParen', $this->_expression(), '');

		return $result;

	}



	/**

	 * It parses a term. It assumes the following rule:

	 * Term -> Fact [("*" | "/") Fact]

	 *

	 * @access private

	 * @return mixed The parsed ptg'd tree on success

	 */

	function _term()

	{

		$result = $this->_fact();

		while (($this->_current_token == "*") or

			   ($this->_current_token == "/")) {

		/**/

			if ($this->_current_token == "*") {

				$this->_advance();

				$result2 = $this->_fact();

				$result = $this->_createTree('ptgMul', $result, $result2);

			} else {

				$this->_advance();

				$result2 = $this->_fact();

				$result = $this->_createTree('ptgDiv', $result, $result2);

			}

		}

		return $result;

	}



	/**

	 * It parses a factor. It assumes the following rule:

	 * Fact -> ( Expr )

	 *       | CellRef

	 *       | CellRange

	 *       | Number

	 *       | Function

	 *

	 * @access private

	 * @return mixed The parsed ptg'd tree on success

	 */

	function _fact()

	{

		if ($this->_current_token == "(") {

			$this->_advance();         // eat the "("

			$result = $this->_parenthesizedExpression();

			if ($this->_current_token != ")") {

				throw new PHPExcel_Writer_Exception("')' token expected.");

			}

			$this->_advance();         // eat the ")"

			return $result;

		}

		// if it's a reference

		if (preg_match('/^\$?[A-Ia-i]?[A-Za-z]\$?[0-9]+$/',$this->_current_token))

		{

			$result = $this->_createTree($this->_current_token, '', '');

			$this->_advance();

			return $result;

		}

		// If it's an external reference (Sheet1!A1 or Sheet1:Sheet2!A1 or Sheet1!$A$1 or Sheet1:Sheet2!$A$1)

		elseif (preg_match("/^" . self::REGEX_SHEET_TITLE_UNQUOTED . "(\:" . self::REGEX_SHEET_TITLE_UNQUOTED . ")?\!\\$?[A-Ia-i]?[A-Za-z]\\$?[0-9]+$/u",$this->_current_token))

		{

			$result = $this->_createTree($this->_current_token, '', '');

			$this->_advance();

			return $result;

		}

		// If it's an external reference ('Sheet1'!A1 or 'Sheet1:Sheet2'!A1 or 'Sheet1'!$A$1 or 'Sheet1:Sheet2'!$A$1)

		elseif (preg_match("/^'" . self::REGEX_SHEET_TITLE_QUOTED . "(\:" . self::REGEX_SHEET_TITLE_QUOTED . ")?'\!\\$?[A-Ia-i]?[A-Za-z]\\$?[0-9]+$/u",$this->_current_token))

		{

			$result = $this->_createTree($this->_current_token, '', '');

			$this->_advance();

			return $result;

		}

		// if it's a range A1:B2 or $A$1:$B$2

		elseif (preg_match('/^(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+:(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+$/',$this->_current_token) or

				preg_match('/^(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+\.\.(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+$/',$this->_current_token))

		{

			// must be an error?

			$result = $this->_createTree($this->_current_token, '', '');

			$this->_advance();

			return $result;

		}

		// If it's an external range (Sheet1!A1:B2 or Sheet1:Sheet2!A1:B2 or Sheet1!$A$1:$B$2 or Sheet1:Sheet2!$A$1:$B$2)

		elseif (preg_match("/^" . self::REGEX_SHEET_TITLE_UNQUOTED . "(\:" . self::REGEX_SHEET_TITLE_UNQUOTED . ")?\!\\$?([A-Ia-i]?[A-Za-z])?\\$?[0-9]+:\\$?([A-Ia-i]?[A-Za-z])?\\$?[0-9]+$/u",$this->_current_token))

		{

			// must be an error?

			//$result = $this->_current_token;

			$result = $this->_createTree($this->_current_token, '', '');

			$this->_advance();

			return $result;

		}

		// If it's an external range ('Sheet1'!A1:B2 or 'Sheet1'!A1:B2 or 'Sheet1'!$A$1:$B$2 or 'Sheet1'!$A$1:$B$2)

		elseif (preg_match("/^'" . self::REGEX_SHEET_TITLE_QUOTED . "(\:" . self::REGEX_SHEET_TITLE_QUOTED . ")?'\!\\$?([A-Ia-i]?[A-Za-z])?\\$?[0-9]+:\\$?([A-Ia-i]?[A-Za-z])?\\$?[0-9]+$/u",$this->_current_token))

		{

			// must be an error?

			//$result = $this->_current_token;

			$result = $this->_createTree($this->_current_token, '', '');

			$this->_advance();

			return $result;

		}

		// If it's a number or a percent

		elseif (is_numeric($this->_current_token))

		{

		    if($this->_lookahead == '%'){

		        $result = $this->_createTree('ptgPercent', $this->_current_token, '');

		    } else {

		        $result = $this->_createTree($this->_current_token, '', '');

		    }

		    $this->_advance();

		    return $result;

		}

		// if it's a function call

		elseif (preg_match("/^[A-Z0-9\xc0-\xdc\.]+$/i",$this->_current_token))

		{

			$result = $this->_func();

			return $result;

		}

		throw new PHPExcel_Writer_Exception("Syntax 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]* )

	 *

	 * @access private

	 * @return mixed The parsed ptg'd tree on success

	 */

	function _func()

	{

		$num_args = 0; // number of arguments received

		$function = strtoupper($this->_current_token);

		$result   = ''; // initialize result

		$this->_advance();

		$this->_advance();         // eat the "("

		while ($this->_current_token != ')') {

		/**/

			if ($num_args > 0) {

				if ($this->_current_token == "," or

					$this->_current_token == ";")

				{

					$this->_advance();  // eat the "," or ";"

				} else {

					throw new PHPExcel_Writer_Exception("Syntax error: comma expected in ".

									  "function $function, arg #{$num_args}");

				}

				$result2 = $this->_condition();

				$result = $this->_createTree('arg', $result, $result2);

			} else { // first argument

				$result2 = $this->_condition();

				$result = $this->_createTree('arg', '', $result2);

			}

			++$num_args;

		}

		if (!isset($this->_functions[$function])) {

			throw new PHPExcel_Writer_Exception("Function $function() doesn't exist");

		}

		$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)) {

			throw new PHPExcel_Writer_Exception("Incorrect number of arguments in function $function() ");

		}



		$result = $this->_createTree($function, $result, $num_args);

		$this->_advance();         // eat the ")"

		return $result;

	}



	/**

	 * Creates a tree. In fact an array which may have one or two arrays (sub-trees)

	 * as elements.

	 *

	 * @access private

	 * @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.

	 * @return array A tree

	 */

	function _createTree($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.

	 * @return string The tree in reverse polish notation

	 */

	function toReversePolish($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'])) {

			$converted_tree = $this->toReversePolish($tree['left']);

			$polish .= $converted_tree;

		} elseif ($tree['left'] != '') { // It's a final node

			$converted_tree = $this->_convert($tree['left']);

			$polish .= $converted_tree;

		}

		if (is_array($tree['right'])) {

			$converted_tree = $this->toReversePolish($tree['right']);

			$polish .= $converted_tree;

		} elseif ($tree['right'] != '') { // It's a final node

			$converted_tree = $this->_convert($tree['right']);

			$polish .= $converted_tree;

		}

		// if it's a function convert it here (so we can set it's arguments)

		if (preg_match("/^[A-Z0-9\xc0-\xdc\.]+$/",$tree['value']) and

			!preg_match('/^([A-Ia-i]?[A-Za-z])(\d+)$/',$tree['value']) and

			!preg_match("/^[A-Ia-i]?[A-Za-z](\d+)\.\.[A-Ia-i]?[A-Za-z](\d+)$/",$tree['value']) and

			!is_numeric($tree['value']) and

			!isset($this->ptg[$tree['value']]))

		{

			// left subtree for a function is always an array.

			if ($tree['left'] != '') {

				$left_tree = $this->toReversePolish($tree['left']);

			} else {

				$left_tree = '';

			}

			// add it's left subtree and return.

			return $left_tree.$this->_convertFunction($tree['value'], $tree['right']);

		} else {

			$converted_tree = $this->_convert($tree['value']);

		}

		$polish .= $converted_tree;

		return $polish;

	}



}

