Index: /issm/trunk/src/c/solvers/solver_nonlinear.cpp
===================================================================
--- /issm/trunk/src/c/solvers/solver_nonlinear.cpp	(revision 7637)
+++ /issm/trunk/src/c/solvers/solver_nonlinear.cpp	(revision 7637)
@@ -0,0 +1,100 @@
+/*!\file: solver_nonlinear.cpp
+ * \brief: core of a non-linear solution, using fixed-point method 
+ */ 
+
+#include "../toolkits/toolkits.h"
+#include "../objects/objects.h"
+#include "../EnumDefinitions/EnumDefinitions.h"
+#include "../modules/modules.h"
+#include "../solutions/solutions.h"
+#include "./solvers.h"
+
+void solver_nonlinear(FemModel* femmodel,bool conserve_loads){
+
+	/*intermediary: */
+	Mat Kgg = NULL, Kff = NULL, Kfs   = NULL;
+	Vec ug  = NULL, uf  = NULL, old_ug= NULL, old_uf = NULL;
+	Vec pg  = NULL, pf  = NULL;
+	Vec dg  = NULL, df  = NULL;
+	
+	Loads* loads=NULL;
+	int converged;
+	int constraints_converged;
+	int num_unstable_constraints;
+	int count;
+
+	/*parameters:*/
+	bool kffpartitioning=false;
+	int min_mechanical_constraints;
+	int max_nonlinear_iterations;
+
+	/*Recover parameters: */
+	femmodel->parameters->FindParam(&kffpartitioning,KffEnum);
+	femmodel->parameters->FindParam(&min_mechanical_constraints,MinMechanicalConstraintsEnum);
+	femmodel->parameters->FindParam(&max_nonlinear_iterations,MaxNonlinearIterationsEnum);
+	
+	/*Were loads requested as output? : */
+	if(conserve_loads) loads=(Loads*)femmodel->loads->Copy(); //protect loads from being modified by the solution
+	else               loads=(Loads*)femmodel->loads;         //modify loads  in this solution
+
+	count=1;
+	converged=0;
+
+	/*Start non-linear iteration using input velocity: */
+	GetSolutionFromInputsx(&ug, femmodel->elements, femmodel->nodes, femmodel->vertices, loads, femmodel->materials, femmodel->parameters);
+	Reducevectorgtofx(&uf, ug, femmodel->nodesets,femmodel->parameters);
+
+	//Update once again the solution to make sure that vx and vxold are similar (for next step in transient or steadystate)
+	InputUpdateFromSolutionx(femmodel->elements,femmodel->nodes, femmodel->vertices, femmodel->loads, femmodel->materials, femmodel->parameters,ug);
+
+	for(;;){
+
+		//save pointer to old velocity
+		VecFree(&old_ug);old_ug=ug;
+		VecFree(&old_uf);old_uf=uf;
+
+		if(kffpartitioning){
+			SystemMatricesx(NULL,&Kff, &Kfs, NULL,&pf, NULL, &df, NULL,femmodel->elements,femmodel->nodes,femmodel->vertices,loads,femmodel->materials,femmodel->parameters);
+			Reduceloadx(pf, Kfs, femmodel->ys); MatFree(&Kfs);
+		}
+		else{
+			SystemMatricesx(&Kgg, NULL, NULL, &pg,NULL, &dg, NULL, NULL,femmodel->elements,femmodel->nodes,femmodel->vertices,loads,femmodel->materials,femmodel->parameters);
+			Reducematrixfromgtofx(&Kff,&Kfs,Kgg,femmodel->nodesets); MatFree(&Kgg);
+			Reduceloadfromgtofx(&pf, pg, Kfs, femmodel->ys, femmodel->nodesets); VecFree(&pg); MatFree(&Kfs);
+			Reducevectorgtofx(&df, dg, femmodel->nodesets,femmodel->parameters); VecFree(&dg);
+		}
+		
+		Solverx(&uf, Kff, pf, old_uf, df, femmodel->parameters);
+		Mergesolutionfromftogx(&ug, uf,femmodel->ys,femmodel->nodesets);
+		InputUpdateFromSolutionx( femmodel->elements,femmodel->nodes, femmodel->vertices, femmodel->loads, femmodel->materials, femmodel->parameters,ug);
+
+		PenaltyConstraintsx(&constraints_converged, &num_unstable_constraints, femmodel->elements,femmodel->nodes,femmodel->vertices,loads,femmodel->materials,femmodel->parameters);
+		_printf_(VerboseConvergence(),"   number of unstable constraints: %i\n",num_unstable_constraints);
+
+		convergence(&converged,Kff,pf,uf,old_uf,femmodel->parameters); MatFree(&Kff);VecFree(&pf); VecFree(&df);
+		InputUpdateFromConstantx( femmodel->elements,femmodel->nodes, femmodel->vertices, femmodel->loads, femmodel->materials, femmodel->parameters,converged,ConvergedEnum);
+
+		//rift convergence
+		if (!constraints_converged) {
+			if (converged){
+				if (num_unstable_constraints <= min_mechanical_constraints) converged=1;
+				else converged=0;
+			}
+		}
+
+		/*Increase count: */
+		count++;
+		if(converged==1)break;
+		if(count>=max_nonlinear_iterations){
+			_printf_(true,"   maximum number of iterations (%i) exceeded\n",max_nonlinear_iterations); 
+			break;
+		}
+	}
+
+	/*clean-up*/
+	if(conserve_loads) delete loads;
+	VecFree(&uf);
+	VecFree(&ug);
+	VecFree(&old_uf);
+	VecFree(&old_ug);
+}
Index: /issm/trunk/src/c/solvers/solvers.h
===================================================================
--- /issm/trunk/src/c/solvers/solvers.h	(revision 7636)
+++ /issm/trunk/src/c/solvers/solvers.h	(revision 7637)
@@ -13,5 +13,5 @@
 
 void solver_thermal_nonlinear(FemModel* femmodel);
-void solver_diagnostic_nonlinear(FemModel* femmodel,bool conserve_loads);
+void solver_nonlinear(FemModel* femmodel,bool conserve_loads);
 void solver_stokescoupling_nonlinear(FemModel* femmodel,bool conserve_loads);
 void solver_linear(FemModel* femmodel);