--- branches/development/src/utils/Grid3d.hpp	2011/11/22 20:38:56	1665
+++ branches/development/src/utils/Grid3d.hpp	2013/02/20 15:39:39	1850
@@ -35,7 +35,7 @@
  *                                                                      
  * [1]  Meineke, et al., J. Comp. Chem. 26, 252-271 (2005).             
  * [2]  Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006).          
- * [3]  Sun, Lin & Gezelter, J. Chem. Phys. 128, 24107 (2008).          
+ * [3]  Sun, Lin & Gezelter, J. Chem. Phys. 128, 234107 (2008).          
  * [4]  Kuang & Gezelter,  J. Chem. Phys. 133, 164101 (2010).
  * [5]  Vardeman, Stocker & Gezelter, J. Chem. Theory Comput. 7, 834 (2011).
  */
@@ -99,8 +99,8 @@ namespace OpenMD {
   private:
     
     int isValidGrid(unsigned int i, unsigned int j, unsigned int k) const {
-      int index = i * dim2_*dim3_ + j * dim3_ + k;
-      return index < data_.size() ? index : -1;
+      unsigned int index = i * dim2_*dim3_ + j * dim3_ + k;
+      return index < data_.size() ? int(index) : -1;
     };
     
     unsigned int dim1_;