diff -u -r1.9 -r1.10
--- SiPixels.java	22 Sep 2009 18:26:53 -0000	1.9
+++ SiPixels.java	22 Sep 2009 18:46:49 -0000	1.10
@@ -137,7 +137,8 @@

 
         for (int irow = row - 1; irow <= row + 1; irow++) {
             for (int icol = col - 1; icol <= col + 1; icol++) {

-                if (irow == 0 && icol == 0) continue;

+//  RP: Not sure why this corner cell was not allowed to be a neighbor - comment out and see if something breaks
+//                if (irow == 0 && icol == 0) continue;

                 int neighbor = getCellID(irow, icol);
                 if (neighbor >= 0) {
                     neighbors.add(neighbor);

@@ -358,7 +359,7 @@

                 int ipixel = getCellID(ixmin + ix, iymin + iy);
 
                 //  Make sure we have a valid pixel

-                if (ipixel >= 0) {

+                if (isValidCell(ipixel)) {

 
                     //  Calculate the charge in this pixel
                     int pixel_charge = (int) Math.round(normalization * prob[ix][iy]);