diff --git a/src/variable.cpp b/src/variable.cpp
index b581e4ce0d..f20c78adc2 100644
--- a/src/variable.cpp
+++ b/src/variable.cpp
@@ -3643,7 +3643,7 @@ tagint Variable::int_between_brackets(char *&ptr, int varallow)
      atan2(y,x),random(x,y,z),normal(x,y,z),ceil(),floor(),round(),ternary(),
      ramp(x,y),stagger(x,y),logfreq(x,y,z),logfreq2(x,y,z),
      logfreq3(x,y,z),stride(x,y,z),stride2(x,y,z,a,b,c),vdisplace(x,y),
-     swiggle(x,y,z),cwiggle(x,y,z)
+     swiggle(x,y,z),cwiggle(x,y,z),sign(x)
 ------------------------------------------------------------------------- */
 
 int Variable::math_function(char *word, char *contents, Tree **tree, Tree **treestack,
diff --git a/src/verlet.cpp b/src/verlet.cpp
index d72383bf4a..0222a0d2a0 100644
--- a/src/verlet.cpp
+++ b/src/verlet.cpp
@@ -282,7 +282,7 @@ void Verlet::run(int n)
       }
       timer->stamp();
       comm->exchange();
-      //if (sortflag && ntimestep >= atom->nextsort) atom->sort();
+      if (sortflag && ntimestep >= atom->nextsort) atom->sort();
       comm->borders();
       if (triclinic) domain->lamda2x(atom->nlocal+atom->nghost);
       timer->stamp(Timer::COMM);