Fixed frontier attempt 4

Author: Diego Vaca

src/simulation/m_bubbles_EL_kernels.fpp

@@ -317,27 +317,51 @@ contains
 
         ! x-dir
         if (bc_x%beg == -2 .and. (cell(1) <= mapCells - 1)) then
-            cellaux(1) = abs(cellaux(1)) - 1
+            if (cell(1) >= 0) then
+                cellaux(1) = abs(cellaux(1)) - 1
+            else
+                print *, "Lagrangian bubbles must not be located in the ghost cells of a symmetric boundary (bc_x%beg)."
+            end if
         end if
         if (bc_x%end == -2 .and. (cell(1) >= m + 1 - mapCells)) then
-            cellaux(1) = cellaux(1) - (2*(cellaux(1) - m) - 1)
+            if (cell(1) <= m) then
+                cellaux(1) = cellaux(1) - (2*(cellaux(1) - m) - 1)
+            else
+                print *, "Lagrangian bubbles must not be located in the ghost cells of a symmetric boundary (bc_x%end)."
+            end if
         end if
 
         !y-dir
         if (bc_y%beg == -2 .and. (cell(2) <= mapCells - 1)) then
-            cellaux(2) = abs(cellaux(2)) - 1
+            if (cell(2) >= 0) then
+                cellaux(2) = abs(cellaux(2)) - 1
+            else
+                print *, "Lagrangian bubbles must not be located in the ghost cells of a symmetric boundary (bc_y%beg)."
+            end if
         end if
         if (bc_y%end == -2 .and. (cell(2) >= n + 1 - mapCells)) then
-            cellaux(2) = cellaux(2) - (2*(cellaux(2) - n) - 1)
+            if (cell(2) <= n) then
+                cellaux(2) = cellaux(2) - (2*(cellaux(2) - n) - 1)
+            else
+                print *, "Lagrangian bubbles must not be located in the ghost cells of a symmetric boundary (bc_y%end)."
+            end if
         end if
 
         if (p > 0) then
             !z-dir
             if (bc_z%beg == -2 .and. (cell(3) <= mapCells - 1)) then
-                cellaux(3) = abs(cellaux(3)) - 1
+                if (cell(3) >= 0) then
+                    cellaux(3) = abs(cellaux(3)) - 1
+                else
+                    print *, "Lagrangian bubbles must not be located in the ghost cells of a symmetric boundary (bc_z%beg)."
+                end if
             end if
             if (bc_z%end == -2 .and. (cell(3) >= p + 1 - mapCells)) then
-                cellaux(3) = cellaux(3) - (2*(cellaux(3) - p) - 1)
+                if (cell(3) <= p) then
+                    cellaux(3) = cellaux(3) - (2*(cellaux(3) - p) - 1)
+                else
+                    print *, "Lagrangian bubbles must not be located in the ghost cells of a symmetric boundary (bc_z%end)."
+                end if
             end if
         end if