adding rowcolToCell() (JT Hughes)

git-svn-id: https://svn.php.net/repository/pear/packages/Spreadsheet_Excel_Writer/trunk@141432 c90b9560-bf6c-de11-be94-00142212c4b1

Writer.php

@@ -71,5 +71,34 @@ class Spreadsheet_Excel_Writer extends Spreadsheet_Excel_Writer_Workbook
         header("Pragma: public");
     }
 
+    /**
+    * Utility function for writing formulas
+    * Converts a cell's coordinates to the A1 format.
+    *
+    * @access public
+    * @static
+    * @param integer $row Row for the cell to convert (0-indexed).
+    * @param integer $col Column for the cell to convert (0-indexed).
+    * @return string The cell identifier in A1 format
+    */
+    function rowcolToCell($row, $col)
+    {
+        if ($col > 255) { //maximum column value exceeded
+            return new PEAR_Error("Maximum column value exceeded: $col");
+        }
+        
+        $int = (int)($col / 26);
+        $frac = $col % 26;
+        $chr1 = '';
+        
+        if ($int > 0) {
+            $chr1 = chr(ord('A') + $int - 1);
+        }
+        
+        $chr2 = chr(ord('A') + $frac);
+        $row++;
+        
+        return $chr1.$chr2.$row;
+    }
 }
 ?>