Index: /issm/trunk-jpl/src/c/analyses/StressbalanceAnalysis.cpp
===================================================================
--- /issm/trunk-jpl/src/c/analyses/StressbalanceAnalysis.cpp	(revision 23839)
+++ /issm/trunk-jpl/src/c/analyses/StressbalanceAnalysis.cpp	(revision 23840)
@@ -871,6 +871,8 @@
 			break;
 		case 11:
+			iomodel->FetchDataToInput(elements,"md.friction.m",FrictionMEnum);
 			iomodel->FetchDataToInput(elements,"md.friction.C",FrictionCEnum);
 			iomodel->FetchDataToInput(elements,"md.friction.Cmax",FrictionCmaxEnum);
+			break;
 		default:
 			_error_("friction law "<< frictionlaw <<" not supported");
@@ -968,5 +970,5 @@
 			break;
 		case 11:
-			parameters->AddObject(iomodel->CopyConstantObject("md.friction.m",FrictionMEnum));
+			parameters->AddObject(new IntParam(FrictionCouplingEnum,2));
 			break;
 		default: _error_("Friction law "<<frictionlaw<<" not implemented yet");
Index: /issm/trunk-jpl/src/c/classes/Loads/Friction.cpp
===================================================================
--- /issm/trunk-jpl/src/c/classes/Loads/Friction.cpp	(revision 23839)
+++ /issm/trunk-jpl/src/c/classes/Loads/Friction.cpp	(revision 23840)
@@ -56,4 +56,9 @@
 	}
 
+
+	/*Checks*/
+	_assert_(!xIsNan<IssmDouble>(*palpha_complement));
+	_assert_(!xIsInf<IssmDouble>(*palpha_complement));
+
 }/*}}}*/
 void Friction::GetAlphaHydroComplement(IssmDouble* palpha_complement, Gauss* gauss){/*{{{*/
@@ -93,5 +98,4 @@
 					(Gamma/As - (alpha*q_exp*pow(Chi,q_exp-1.)* Gamma * Gamma/As));
 
-	_assert_(!xIsNan<IssmDouble>(alpha_complement));
 	/*Assign output pointers:*/
 	*palpha_complement=alpha_complement;
@@ -154,7 +158,4 @@
 	else alpha_complement=pow(Neff,r)*pow(vmag,(s-1));
 
-	_assert_(!xIsNan<IssmDouble>(alpha_complement));
-	_assert_(!xIsInf<IssmDouble>(alpha_complement));
-
 	/*Assign output pointers:*/
 	*palpha_complement=alpha_complement;
@@ -200,4 +201,9 @@
 			_error_("Friction law "<< this->law <<" not supported");
 	}
+
+	/*Checks*/
+	_assert_(!xIsNan<IssmDouble>(*palpha2));
+	_assert_(!xIsInf<IssmDouble>(*palpha2));
+	_assert_(*palpha2>=0);
 
 }/*}}}*/
@@ -245,6 +251,4 @@
 	if(alpha2_coulomb<alpha2) alpha2=alpha2_coulomb;
 
-	_assert_(!xIsNan<IssmDouble>(alpha2));
-
 	/*Assign output pointers:*/
 	*palpha2=alpha2;
@@ -292,5 +296,4 @@
 	else	alpha2=Neff * C_param * pow(Gamma,1./n) * pow(vmag,-1);
 
-	_assert_(!xIsNan<IssmDouble>(alpha2));
 	/*Assign output pointers:*/
 	*palpha2=alpha2;
@@ -324,5 +327,4 @@
 
 	alpha2=drag_coefficient*drag_coefficient*Neff;
-	_assert_(!xIsNan<IssmDouble>(alpha2));
 
 	/*Assign output pointers:*/
@@ -396,8 +398,4 @@
 	alpha2 = alpha2 * exp((deltaTref - deltaT)/(2*gamma));
 
-	/*Final checks in debuging mode*/
-	_assert_(!xIsNan<IssmDouble>(alpha2));
-	_assert_(!xIsInf<IssmDouble>(alpha2));
-
 	/*Assign output pointers:*/
 	*palpha2=alpha2;
@@ -430,5 +428,4 @@
 	if(vmag==0. && (s-1.)<0.) alpha2=0.;
 	else alpha2=drag_coefficient*drag_coefficient*pow(Neff,r)*pow(vmag,(s-1.));
-	_assert_(!xIsNan<IssmDouble>(alpha2));
 
 	/*Assign output pointers:*/
@@ -477,5 +474,4 @@
 	if(vmag==0. && (s-1.)<0.) alpha2=0.;
 	else alpha2=drag_coefficient*drag_coefficient*pow(Neff,r)*pow(vmag,(s-1.));
-	_assert_(!xIsNan<IssmDouble>(alpha2));
 
 	/*Assign output pointers:*/
@@ -500,5 +496,4 @@
 	if(vmag==0. && (1./m-1.)<0.) alpha2=0.;
 	else alpha2=pow(C,-1./m)*pow(vmag,(1./m-1.));
-	_assert_(!xIsNan<IssmDouble>(alpha2));
 
 	/*Assign output pointers:*/
@@ -595,8 +590,4 @@
 	IssmDouble alpha2 = tau_c/(pow(ub+1.e-10,1.-q)*pow(u0,q));
 
-	/*Final checks in debuging mode*/
-	_assert_(!xIsNan<IssmDouble>(alpha2));
-	_assert_(!xIsInf<IssmDouble>(alpha2));
-
 	/*Assign output pointers:*/
 	*palpha2=alpha2;
@@ -613,5 +604,5 @@
 
 	/*diverse: */
-	IssmDouble  C,Cmax,m;
+	IssmDouble  C,Cmax,m,alpha2;
 
 	/*Recover parameters: */
@@ -625,9 +616,10 @@
 
 	/*Compute alpha^2*/
-	IssmDouble alpha2= (C*pow(ub,m-1.)) / pow(1.+  pow(C/(Cmax*N),1./m)*ub,m);
-
-	/*Checks*/
-	_assert_(!xIsNan<IssmDouble>(alpha2));
-	_assert_(alpha2>=0);
+	if(ub<1e-10){
+		alpha2 = 0.;
+	}
+	else{
+		alpha2= (C*pow(ub,m-1.)) / pow(1.+  pow(C/(Cmax*N),1./m)*ub,m);
+	}
 
 	/*Assign output pointers:*/
Index: /issm/trunk-jpl/src/m/classes/frictionschoof.m
===================================================================
--- /issm/trunk-jpl/src/m/classes/frictionschoof.m	(revision 23839)
+++ /issm/trunk-jpl/src/m/classes/frictionschoof.m	(revision 23840)
@@ -8,5 +8,5 @@
 		C    = NaN;
 		Cmax = NaN;
-		m    = 0.;
+		m    = NaN;
 	end
 	methods
@@ -25,7 +25,4 @@
 		function self = setdefaultparameters(self) % {{{
 
-			%default m is 1/n = 1/3
-			self.m = 1./3.;
-
 		end % }}}
 		function md = checkconsistency(self,md,solution,analyses) % {{{
@@ -35,5 +32,5 @@
 			md = checkfield(md,'fieldname','friction.C','timeseries',1,'NaN',1,'Inf',1,'>',0.);
 			md = checkfield(md,'fieldname','friction.Cmax','timeseries',1,'NaN',1,'Inf',1,'>',0.);
-			md = checkfield(md,'fieldname','friction.m','NaN',1,'Inf',1,'numel',1,'>',0.);
+			md = checkfield(md,'fieldname','friction.m','NaN',1,'Inf',1,'>',0.,'size',[md.mesh.numberofelements,1]);
 		end % }}}
 		function disp(self) % {{{
@@ -55,5 +52,5 @@
 			WriteData(fid,prefix,'class','friction','object',self,'fieldname','C','format','DoubleMat','mattype',1,'timeserieslength',md.mesh.numberofvertices+1,'yts',md.constants.yts);
 			WriteData(fid,prefix,'class','friction','object',self,'fieldname','Cmax','format','DoubleMat','mattype',1,'timeserieslength',md.mesh.numberofvertices+1,'yts',md.constants.yts);
-			WriteData(fid,prefix,'class','friction','object',self,'fieldname','m','format','Double');
+			WriteData(fid,prefix,'class','friction','object',self,'fieldname','m','format','DoubleMat','mattype',2);