code: function Misc_ColNum($ColRef, $IsODF) {
  
  		if ($IsODF) {
  			$p = strpos($ColRef, '.');
  			if ($p!==false) $ColRef = substr($ColRef, $p); // delete the table name wich is in prefix
  			$ColRef = str_replace( array('.','$'), '', $ColRef);
  			$ColRef = explode(':', $ColRef);
  			$ColRef = $ColRef[0];
  		}
  
  		$num = 0;
  		$rank = 0;
  		for ($i=strlen($ColRef)-1;$i>=0;$i--) {
  			$l = $ColRef[$i];
  			if (!is_numeric($l)) {
  				$l = ord(strtoupper($l)) -64;
  				if ($l>0 && $l<27) {
  					$num = $num + $l*pow(26,$rank);
  				} else {
  					return $this->RaiseError('(Sheet) Reference of cell \''.$ColRef.'\' cannot be recognized.');
  				}
  				$rank++;
  			}
  		}
  
  		return $num;
  
  	}
docs: Return the column number from a cell reference like "B3".