Index: ../trunk-jpl/src/m/exp/flowlines.m
===================================================================
--- ../trunk-jpl/src/m/exp/flowlines.m	(revision 20511)
+++ ../trunk-jpl/src/m/exp/flowlines.m	(revision 20512)
@@ -87,7 +87,7 @@
 	end
 
 	%velocity of the current triangle and norm it
-	ut=u(tria); vt=v(tria); normv=sqrt(ut.^2+vt.^2);
+	ut=u(tria); vt=v(tria); normv=max(eps,sqrt(ut.^2+vt.^2));
 	ut=ut./normv;vt=vt./normv;
 
 	%check counter
@@ -137,7 +137,7 @@
 	end
 
 	%velocity of the current triangle and norm it
-	ut=-u(tria); vt=-v(tria); normv=sqrt(ut.^2+vt.^2);
+	ut=-u(tria); vt=-v(tria); normv=max(eps,sqrt(ut.^2+vt.^2));
 	ut=ut./normv;vt=vt./normv;
 
 	%check counter