diff --git a/src/read_dump.cpp b/src/read_dump.cpp
index f5c9ddc850..164496c762 100644
--- a/src/read_dump.cpp
+++ b/src/read_dump.cpp
@@ -584,21 +584,11 @@ int ReadDump::fields_and_keywords(int narg, char **arg)
 
   iarg = 0;
   while (iarg < narg) {
-    if (strcmp(arg[iarg],"x") == 0) fieldtype[nfield++] = X;
-    else if (strcmp(arg[iarg],"y") == 0) fieldtype[nfield++] = Y;
-    else if (strcmp(arg[iarg],"z") == 0) fieldtype[nfield++] = Z;
-    else if (strcmp(arg[iarg],"vx") == 0) fieldtype[nfield++] = VX;
-    else if (strcmp(arg[iarg],"vy") == 0) fieldtype[nfield++] = VY;
-    else if (strcmp(arg[iarg],"vz") == 0) fieldtype[nfield++] = VZ;
-    else if (strcmp(arg[iarg],"q") == 0) {
-      if (!atom->q_flag)
-        error->all(FLERR,"Read dump of atom property that isn't allocated");
-      fieldtype[nfield++] = Q;
-    }
-    else if (strcmp(arg[iarg],"ix") == 0) fieldtype[nfield++] = IX;
-    else if (strcmp(arg[iarg],"iy") == 0) fieldtype[nfield++] = IY;
-    else if (strcmp(arg[iarg],"iz") == 0) fieldtype[nfield++] = IZ;
-    else break;
+    int type = whichtype(arg[iarg]);
+    if (type < 0) break;
+    if (type == Q && !atom->q_flag)
+      error->all(FLERR,"Read dump of atom property that isn't allocated");
+    fieldtype[nfield++] = type;
     iarg++;
   }
 
@@ -662,9 +652,10 @@ int ReadDump::fields_and_keywords(int narg, char **arg)
       iarg += 2;
     } else if (strcmp(arg[iarg],"label") == 0) {
       if (iarg+3 > narg) error->all(FLERR,"Illegal read_dump command");
+      int type = whichtype(arg[iarg+1]);
       int i;
       for (i = 0; i < nfield; i++)
-        if (fieldlabel[i] && strcmp(arg[iarg+1],fieldlabel[i]) == 0) break;
+        if (type == fieldtype[i]) break;
       if (i == nfield) error->all(FLERR,"Illegal read_dump command");
       int n = strlen(arg[iarg+2]) + 1;
       fieldlabel[i] = new char[n];
@@ -699,6 +690,28 @@ int ReadDump::fields_and_keywords(int narg, char **arg)
   return narg-iarg;
 }
 
+/* ----------------------------------------------------------------------
+   check if str is a field argument
+   if yes, return index of which
+   if not, return -1
+------------------------------------------------------------------------- */
+
+int ReadDump::whichtype(char *str)
+{
+  int type = -1;
+  if (strcmp(str,"x") == 0) type = X;
+  else if (strcmp(str,"y") == 0) type = Y;
+  else if (strcmp(str,"z") == 0) type = Z;
+  else if (strcmp(str,"vx") == 0) type = VX;
+  else if (strcmp(str,"vy") == 0) type = VY;
+  else if (strcmp(str,"vz") == 0) type = VZ;
+  else if (strcmp(str,"q") == 0) type = Q;
+  else if (strcmp(str,"ix") == 0) type = IX;
+  else if (strcmp(str,"iy") == 0) type = IY;
+  else if (strcmp(str,"iz") == 0) type = IZ;
+  return type;
+}
+
 /* ----------------------------------------------------------------------
    process each of N atoms in chunk read from dump file
    if in replace mode and atom ID matches current atom,
diff --git a/src/read_dump.h b/src/read_dump.h
index 168acff1ce..95a7306fd5 100644
--- a/src/read_dump.h
+++ b/src/read_dump.h
@@ -82,6 +82,7 @@ private:
 
   class Reader *reader;           // class that reads dump file
 
+  int whichtype(char *);
   void process_atoms(int);
   void delete_atoms();