Index: /issm/trunk-jpl/src/c/solutionsequences/solutionsequence_fct.cpp
===================================================================
--- /issm/trunk-jpl/src/c/solutionsequences/solutionsequence_fct.cpp	(revision 18356)
+++ /issm/trunk-jpl/src/c/solutionsequences/solutionsequence_fct.cpp	(revision 18357)
@@ -236,4 +236,6 @@
 		//double Qi_plus  = ml_serial[row]/deltat*(ulmax[row] - u[row]);
 		//double Qi_minus = ml_serial[row]/deltat*(ulmin[row] - u[row]);
+		_assert_(Qi_plus  >= 0.);
+		_assert_(Qi_minus <= 0.);
 		d = 1.;
 		if(Pi_plus!=0.) d = min(1.,Qi_plus/Pi_plus);