diff --git a/src/compute_reduce.cpp b/src/compute_reduce.cpp
index d226c0585d..9342cb1c80 100644
--- a/src/compute_reduce.cpp
+++ b/src/compute_reduce.cpp
@@ -350,7 +350,8 @@ double ComputeReduce::compute_scalar()
     MPI_Allreduce(&one,&scalar,1,MPI_DOUBLE,MPI_MAX,world);
   } else if (mode == AVE) {
     MPI_Allreduce(&one,&scalar,1,MPI_DOUBLE,MPI_SUM,world);
-    scalar /= count(0);
+    bigint n = count(0);
+    if (n) scalar /= n;
   }
 
   return scalar;
@@ -419,7 +420,8 @@ void ComputeReduce::compute_vector()
   } else if (mode == AVE) {
     for (int m = 0; m < nvalues; m++) {
       MPI_Allreduce(&onevec[m],&vector[m],1,MPI_DOUBLE,MPI_SUM,world);
-      vector[m] /= count(m);
+      bigint n = count(m);
+      if (n) vector[m] /= n;
     }
   }
 }
diff --git a/src/fix_store_state.cpp b/src/fix_store_state.cpp
index 54c94ad050..7f49140d57 100644
--- a/src/fix_store_state.cpp
+++ b/src/fix_store_state.cpp
@@ -440,7 +440,7 @@ void FixStoreState::end_of_step()
       // evaluate atom-style variable
       
       } else if (which[m] == VARIABLE)
-	input->variable->compute_atom(n,igroup,&values[0][m],nvalues,1);
+	input->variable->compute_atom(n,igroup,&values[0][m],nvalues,0);
     }
   }
 
diff --git a/src/variable.cpp b/src/variable.cpp
index 22286ee5d2..d98897df69 100644
--- a/src/variable.cpp
+++ b/src/variable.cpp
@@ -210,6 +210,7 @@ void Variable::set(int narg, char **arg)
       if (nvar == maxvar) extend();
       style[nvar] = UNIVERSE;
       num[nvar] = narg - 2;
+      pad[nvar] = 0;
       data[nvar] = new char*[num[nvar]];
       copy(num[nvar],&arg[2],data[nvar]);
     } else if (strcmp(arg[1],"uloop") == 0) {
@@ -500,7 +501,7 @@ void Variable::compute_atom(int ivar, int igroup,
   if (sumflag == 0) {
     int m = 0;
     for (int i = 0; i < nlocal; i++) {
-      if (mask[i] && groupbit) result[m] = eval_tree(tree,i);
+      if (mask[i] & groupbit) result[m] = eval_tree(tree,i);
       else result[m] = 0.0;
       m += stride;
     }