Index: /issm/trunk/src/c/Container/Inputs.cpp
===================================================================
--- /issm/trunk/src/c/Container/Inputs.cpp	(revision 5681)
+++ /issm/trunk/src/c/Container/Inputs.cpp	(revision 5682)
@@ -99,4 +99,32 @@
 }
 /*}}}*/
+/*FUNCTION Inputs::GetParameterValue(double* pvalue,GaussTria* gauss,int enum_type){{{1*/
+void Inputs::GetParameterValue(double* pvalue,GaussPenta* gauss, int enum_type){
+
+	vector<Object*>::iterator object;
+	Input* input=NULL;
+	bool   found=false;
+
+	/*Go through inputs and check whether any input with the same name is already in: */
+	for ( object=objects.begin() ; object < objects.end(); object++ ){
+
+		input=(Input*)(*object); 
+		if (input->EnumType()==enum_type){
+			found=true;
+			break;
+		}
+	}
+
+	if (!found){
+		/*we could not find an input with the correct enum type. No defaults values were provided, 
+		 * error out: */
+		ISSMERROR("could not find input with enum type %i (%s)",enum_type,EnumToString(enum_type));
+	}
+
+	/*Ok, we have an input if we made it here, request the input to return the values: */
+	input->GetParameterValue(pvalue,gauss);
+
+}
+/*}}}*/
 /*FUNCTION Inputs::GetParameterValue(double* pvalue,double* gauss,int enum_type,double defaultvalue){{{1*/
 void Inputs::GetParameterValue(double* pvalue,double* gauss, int enum_type,double defaultvalue){
Index: /issm/trunk/src/c/Container/Inputs.h
===================================================================
--- /issm/trunk/src/c/Container/Inputs.h	(revision 5681)
+++ /issm/trunk/src/c/Container/Inputs.h	(revision 5682)
@@ -17,4 +17,5 @@
 class Node;
 class GaussTria;
+class GaussPenta;
 
 class Inputs: public DataSet{
@@ -49,4 +50,5 @@
 		void GetParameterValue(double* pvalue,double* gauss,int enum_type);
 		void GetParameterValue(double* pvalue,GaussTria* gauss,int enum_type);
+		void GetParameterValue(double* pvalue,GaussPenta* gauss,int enum_type);
 		void GetParameterValue(double* pvalue,double* gauss,int enum_type,double defaultvalue);
 		void GetParameterDerivativeValue(double* derivativevalues, double* xyz_list, double* gauss,int enum_type);
Index: /issm/trunk/src/c/objects/Elements/Penta.cpp
===================================================================
--- /issm/trunk/src/c/objects/Elements/Penta.cpp	(revision 5681)
+++ /issm/trunk/src/c/objects/Elements/Penta.cpp	(revision 5682)
@@ -2879,5 +2879,5 @@
 
 			/*Calculate DL on gauss point */
-			friction->GetAlpha2(&alpha2_gauss, gauss_tria,VxEnum,VyEnum,VzEnum);
+			friction->GetAlpha2(&alpha2_gauss, gauss,VxEnum,VyEnum,VzEnum);
 
 			DLStokes[0][0]=alpha2_gauss*gauss->weight*Jdet2d;
Index: /issm/trunk/src/c/objects/Loads/Friction.cpp
===================================================================
--- /issm/trunk/src/c/objects/Loads/Friction.cpp	(revision 5681)
+++ /issm/trunk/src/c/objects/Loads/Friction.cpp	(revision 5682)
@@ -177,4 +177,65 @@
 }
 /*}}}*/
+/*FUNCTION Friction::GetAlpha2{{{1*/
+void Friction::GetAlpha2(double* palpha2, GaussPenta* gauss,int vxenum,int vyenum,int vzenum){
+
+	/*This routine calculates the basal friction coefficient 
+	  alpha2= drag^2 * Neff ^r * vel ^s, with Neff=rho_ice*g*thickness+rho_ice*g*bed, r=q/p and s=1/p**/
+
+	/*diverse: */
+	double  r,s;
+	double  drag_p, drag_q;
+	double  gravity,rho_ice,rho_water;
+	double  Neff;
+	double  thickness,bed;
+	double  vx,vy,vz,vmag;
+	double  drag_coefficient;
+	double  alpha2;
+
+
+	/*Recover parameters: */
+	inputs->GetParameterValue(&drag_p,DragPEnum);
+	inputs->GetParameterValue(&drag_q,DragQEnum);
+	inputs->GetParameterValue(&thickness, gauss,ThicknessEnum);
+	inputs->GetParameterValue(&bed, gauss,BedEnum);
+	inputs->GetParameterValue(&drag_coefficient, gauss,DragCoefficientEnum);
+
+	/*Get material parameters: */
+	gravity=matpar->GetG();
+	rho_ice=matpar->GetRhoIce();
+	rho_water=matpar->GetRhoWater();
+
+	//compute r and q coefficients: */
+	r=drag_q/drag_p;
+	s=1./drag_p;
+
+	//From bed and thickness, compute effective pressure when drag is viscous:
+	Neff=gravity*(rho_ice*thickness+rho_water*bed);
+
+	/*If effective pressure becomes negative, sliding becomes unstable (Paterson 4th edition p 148). This is because 
+	  the water pressure is so high, the ice sheet elevates over its ice bumps and slides. But the limit behaviour 
+	  for friction should be an ice shelf sliding (no basal drag). Therefore, for any effective pressure Neff < 0, we should 
+	  replace it by Neff=0 (ie, equival it to an ice shelf)*/
+	if (Neff<0)Neff=0;
+
+	if(strcmp(element_type,"2d")==0){
+		inputs->GetParameterValue(&vx, gauss,vxenum);
+		inputs->GetParameterValue(&vy, gauss,vyenum);
+		vmag=sqrt(pow(vx,2)+pow(vy,2));
+	}
+	else if (strcmp(element_type,"3d")==0){
+		inputs->GetParameterValue(&vx, gauss,vxenum);
+		inputs->GetParameterValue(&vy, gauss,vyenum);
+		inputs->GetParameterValue(&vz, gauss,vzenum);
+		vmag=sqrt(pow(vx,2)+pow(vy,2)+pow(vz,2));
+	}
+	else ISSMERROR("element_type %s not supported yet",element_type);
+
+	alpha2=pow(drag_coefficient,2)*pow(Neff,r)*pow(vmag,(s-1));
+
+	/*Assign output pointers:*/
+	*palpha2=alpha2;
+}
+/*}}}*/
 /*FUNCTION Friction::GetAlphaComplement {{{1*/
 void Friction::GetAlphaComplement(double* palpha_complement, double* gauss,int vxenum,int vyenum){
Index: /issm/trunk/src/c/objects/Loads/Friction.h
===================================================================
--- /issm/trunk/src/c/objects/Loads/Friction.h	(revision 5681)
+++ /issm/trunk/src/c/objects/Loads/Friction.h	(revision 5682)
@@ -29,4 +29,5 @@
 		void  GetAlpha2(double* palpha2, double* gauss,int vxenum,int vyenum,int vzenum);
 		void  GetAlpha2(double* palpha2, GaussTria* gauss,int vxenum,int vyenum,int vzenum);
+		void  GetAlpha2(double* palpha2, GaussPenta* gauss,int vxenum,int vyenum,int vzenum);
 		void  GetAlphaComplement(double* alpha_complement, double* gauss,int vxenum,int vyenum);
 		void  GetAlphaComplement(double* alpha_complement, GaussTria* gauss,int vxenum,int vyenum);