From 67503ebecc3f35cdbe93ea7f775e65cf79cc55c3 Mon Sep 17 00:00:00 2001
From: sjplimp <sjplimp@f3b2605a-c512-4ea7-a41b-209d697bcdaa>
Date: Fri, 22 Mar 2013 22:16:40 +0000
Subject: [PATCH] git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@9707
 f3b2605a-c512-4ea7-a41b-209d697bcdaa

---
 src/fix_external.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/fix_external.cpp b/src/fix_external.cpp
index c9083e0334..8cddd0dbce 100644
--- a/src/fix_external.cpp
+++ b/src/fix_external.cpp
@@ -110,13 +110,13 @@ void FixExternal::post_force(int vflag)
   // invoke the callback in driver program
   // it will fill fexternal with forces
 
-  if (mode == PF_CALLBACK && ntimestep & ncall == 0)
+  if (mode == PF_CALLBACK && ntimestep % ncall == 0)
     (this->callback)(ptr_caller,update->ntimestep,
                      atom->nlocal,atom->tag,atom->x,fexternal);
 
   // add forces from fexternal to atoms in group
 
-  if (ntimestep & napply == 0) {
+  if (ntimestep % napply == 0) {
     double **f = atom->f;
     int *mask = atom->mask;
     int nlocal = atom->nlocal;