diff --git a/PHPExcel/PHPExcel/Calculation/Functions.php b/PHPExcel/PHPExcel/Calculation/Functions.php
index 5a1e5ee..773ce1a 100755
--- a/PHPExcel/PHPExcel/Calculation/Functions.php
+++ b/PHPExcel/PHPExcel/Calculation/Functions.php
@@ -318,10 +318,10 @@ class PHPExcel_Calculation_Functions
     public static function ifCondition($condition)
     {
         $condition    = PHPExcel_Calculation_Functions::flattenSingleValue($condition);
-        if (!isset($condition{0})) {
+        if (!isset($condition[0])) {
             $condition = '=""';
         }
-        if (!in_array($condition{0}, array('>', '<', '='))) {
+        if (!in_array($condition[0], array('>', '<', '='))) {
             if (!is_numeric($condition)) {
                 $condition = PHPExcel_Calculation::wrapResult(strtoupper($condition));
             }
@@ -559,7 +559,7 @@ class PHPExcel_Calculation_Functions
                 return (integer) $value;
             case 'string':
                 //    Errors
-                if ((strlen($value) > 0) && ($value{0} == '#')) {
+                if ((strlen($value) > 0) && ($value[0] == '#')) {
                     return $value;
                 }
                 break;
@@ -609,7 +609,7 @@ class PHPExcel_Calculation_Functions
                 return 64;
         } elseif (is_string($value)) {
             //    Errors
-            if ((strlen($value) > 0) && ($value{0} == '#')) {
+            if ((strlen($value) > 0) && ($value[0] == '#')) {
                 return 16;
             }
             return 2;