Index: /issm/trunk-jpl/src/c/cores/controlvalidation_core.cpp
===================================================================
--- /issm/trunk-jpl/src/c/cores/controlvalidation_core.cpp	(revision 18616)
+++ /issm/trunk-jpl/src/c/cores/controlvalidation_core.cpp	(revision 18617)
@@ -15,4 +15,5 @@
 	IssmDouble  j0,j,yts;
 	IssmDouble  Ialpha,exponent,alpha;
+	IssmDouble* scaling_factors = NULL;
 	IssmDouble* jlist = NULL;
 	IssmDouble *G = NULL;
@@ -29,4 +30,5 @@
 	femmodel->parameters->FindParam(&num_responses,InversionNumCostFunctionsEnum);
 	femmodel->parameters->FindParam(&yts,ConstantsYtsEnum);
+	femmodel->parameters->FindParam(&scaling_factors,NULL,InversionControlScalingFactorsEnum);
 
 	/*Get initial guess*/
@@ -51,9 +53,5 @@
 	if(VerboseControl()) _printf0_("   Compute Initial cost function\n");
 	femmodel->CostFunctionx(&j0,&jlist,NULL);
-	_printf0_("Initial J(x+dk)      |  List of contributions\n");
-	_printf0_("_____________________________________________\n");
-	_printf0_("J(x) = "<<setw(12)<<setprecision(7)<<j0<<"  |  ");
-	for(int i=0;i<num_responses;i++) _printf0_(" "<<setw(12)<<setprecision(7)<<jlist[i]);
-	_printf0_("\n");
+	_printf0_("Initial cost function J(x) = "<<setw(12)<<setprecision(7)<<j0<<"\n");
 	xDelete<IssmDouble>(jlist);
 
@@ -62,11 +60,6 @@
 	for(int i=0;i<n;i++) G[i] = -G[i];
 
-	/*Range of tests*/
-	IssmDouble exp0 = 0.;
-	IssmDouble incr = -0.2;
-	IssmDouble exp1 = -18.;
-	int        num  = reCast<int,IssmDouble>((exp1-exp0)/incr);
-
 	/*Allocate output*/
+	int num = 26;
 	IssmDouble* output = xNew<IssmDouble>(2*num);
 
@@ -76,9 +69,6 @@
 	for(int m=0;m<num;m++){
 
-		/*Calculate alpha = 10^-exponent*/
-		exponent = exp0+m*incr;
-		alpha    = pow(10.,exponent);
-
 		/*Create new vector*/
+		alpha    = pow(2.,-m);
 		for(int i=0;i<n;i++) X[i] = X0[i] + alpha;
 
@@ -89,5 +79,5 @@
 
 		IssmDouble Den = 0.;
-		for(int i=0;i<n;i++) Den += alpha* G[i] * 1.;
+		for(int i=0;i<n;i++) Den += alpha* G[i] * scaling_factors[0];
 		Ialpha = fabs((j - j0)/Den - 1.);
 
Index: /issm/trunk-jpl/src/c/modules/ModelProcessorx/Control/CreateParametersControl.cpp
===================================================================
--- /issm/trunk-jpl/src/c/modules/ModelProcessorx/Control/CreateParametersControl.cpp	(revision 18616)
+++ /issm/trunk-jpl/src/c/modules/ModelProcessorx/Control/CreateParametersControl.cpp	(revision 18617)
@@ -78,4 +78,6 @@
 				break;
 			case 3:/*Validation*/
+				iomodel->FetchData(&control_scaling_factors,NULL,NULL,InversionControlScalingFactorsEnum);
+				parameters->AddObject(new DoubleVecParam(InversionControlScalingFactorsEnum,control_scaling_factors,num_controls));
 				break;
 			default:
Index: /issm/trunk-jpl/src/m/classes/inversionvalidation.m
===================================================================
--- /issm/trunk-jpl/src/m/classes/inversionvalidation.m	(revision 18616)
+++ /issm/trunk-jpl/src/m/classes/inversionvalidation.m	(revision 18617)
@@ -9,4 +9,5 @@
 		incomplete_adjoint          = 0
 		control_parameters          = NaN
+		control_scaling_factors     = NaN
 		cost_functions              = NaN
 		cost_functions_coefficients = NaN
@@ -40,4 +41,7 @@
 			self.control_parameters={'FrictionCoefficient'};
 
+			%Scaling factor for each control
+			self.control_scaling_factors=1;
+
 			%several responses can be used:
 			self.cost_functions=101;
@@ -56,4 +60,5 @@
 				{'BalancethicknessThickeningRate' 'FrictionCoefficient' 'MaterialsRheologyBbar' 'DamageDbar' 'Vx' 'Vy' 'Thickness',...
 				'BalancethicknessOmega' 'BalancethicknessApparentMassbalance'});
+			md = checkfield(md,'fieldname','inversion.control_scaling_factors','size',[1 num_controls],'>',0,'NaN',1);
 			md = checkfield(md,'fieldname','inversion.cost_functions','size',[1 num_costfunc],'values',[101:105 201 501:506 601:604]);
 			md = checkfield(md,'fieldname','inversion.cost_functions_coefficients','size',[md.mesh.numberofvertices num_costfunc],'>=',0);
@@ -77,4 +82,5 @@
 			fielddisplay(obj,'incomplete_adjoint','1: linear viscosity, 0: non-linear viscosity');
 			fielddisplay(obj,'control_parameters','ex: {''FrictionCoefficient''}, or {''MaterialsRheologyBbar''}');
+			fielddisplay(obj,'control_scaling_factors','order of magnitude of each control (useful for multi-parameter optimization)');
 			fielddisplay(obj,'cost_functions','indicate the type of response for each optimization step');
 			fielddisplay(obj,'cost_functions_coefficients','cost_functions_coefficients applied to the misfit of each vertex and for each control_parameter');
@@ -105,4 +111,5 @@
 			if ~obj.iscontrol, return; end
 			WriteData(fid,'object',obj,'class','inversion','fieldname','incomplete_adjoint','format','Boolean');
+			WriteData(fid,'object',obj,'class','inversion','fieldname','control_scaling_factors','format','DoubleMat','mattype',3);
 			WriteData(fid,'object',obj,'class','inversion','fieldname','cost_functions_coefficients','format','DoubleMat','mattype',1);
 			WriteData(fid,'object',obj,'class','inversion','fieldname','min_parameters','format','DoubleMat','mattype',3);