
Support XLS functions


* Funct. cells

  _CELL( nRow, nCol [, lAbsRefRow] [, lAbsRefCol] )

  _SUM( nIniRow, nIniCol, nEndRow, nEndCol [, lAbsRefIniRow ] [, lAbsRefIniCol ] [, lAbsRefEndRow ] [, lAbsRefEndCol] )
  _MULT( nIniRow, nIniCol, nEndRow, nEndCol [, lAbsRefIniRow ] [, lAbsRefIniCol ] [, lAbsRefEndRow ] [, lAbsRefEndCol] )


* Funct. Math.

  _ABS( Number )
  _INTE( Number )
  _MOD( Dividend, Divisor ) 
  _ROUND( Number, Decimals )    
  _SIGN( Number )

  _SQRT( Number )
  _EXP( Number )
  _LN( Number )
  _LOG( Number )

  _PI()
  _RANDOM()

  _SIN( Angle )
  _COS( Angle )
  _TAN( Angle )
  _ASIN( Sin )
  _ACOS( Cos )
  _ATAN( Tan )