Changes steplength calculation for L-BFGS

test steplength set to 0.5 aand 1.0

par/in_and_out/ifos3d.inp

@@ -40,7 +40,7 @@ point_source_(explosive=1;force_in_x=2;in_y=3;in_z=4;custom=5)_(QUELLTYP) = 4
 force_angle_between_x_y_(in_degree)_(ALPHA) = 45.0
 force_angle_between_x_z_(in_degree)_(BETA) =  45.0
 # Plane wave (PW) excitation,if PLANE_WAVE_DEPTH>0, SRCREC is treated as 0
-depth_of_PW_excitation_(no<=0)_(in_meter)_(PLANE_WAVE_DEPTH) = 0.0direct.com/
+depth_of_PW_excitation_(no<=0)_(in_meter)_(PLANE_WAVE_DEPTH) = 0.0
 dip_of_PW_from_vertical_(in_degrees)_(PHI) =0.0
 duration_of_source-signal_PW_(in_seconds)_(TS) = 0.0033
 # External signal input instead of QUELLART

src/fd.h

@@ -367,7 +367,7 @@ void zero_invers(int NX, int NY, int NZ, float **** Ffvx, float **** Ffvy, float
 void precon_grad(int nx,int ny,int nz, float ***grad1, float ***grad2,float ***grad3, int nsrc, float **  srcpos, int ntr_glob, int **recpos, float finv, int iteration,int cdf);
 void outgrad(int nx,int ny,int nz,float ***grad1, float ***grad2,float ***grad3, float finv, int iteration, char outfile[STRING_SIZE]);
 void outmod(int nx,int ny,int nz,float ***rho, float ***pi,float ***u, int iteration);
-void steplength(float *L2, float * step, int iteration);
+void steplength(float *L2, float * step, int iteration, int it_group);
 void zero_grad(int NX, int NY, int NZ, float *** grad1, float *** grad2, float *** grad3);
 void cpmodel(int nx, int ny, int nz, float ***rho, float ***pi, float ***u,float  ***  testrho, float ***  testpi, float ***  testu);
 void conjugate(int nx,int ny,int nz, float ***grad1, float ***grad2,float ***grad3, float ***gradprior1, float ***gradprior2, float ***gradprior3, float ***gradprior4, float ***gradprior5, float ***gradprior6,float *beta, int iteration,int cdf);

src/ifos3d.c

@@ -1003,13 +1003,9 @@ CPML_coeff(K_x,alpha_prime_x,a_x,b_x,K_x_half,alpha_prime_x_half,a_x_half,b_x_ha
 			fprintf(FP,"\n STEPLENGTH CALCULATION ITERATION %d \n", iteration);
 				if(LBFGS||!LBFGS){
 			for (steptest=1;steptest<=2;steptest++){
-				if(cdf==1) step[4]=0.02;
-				/*if(cdf==1)step[4]=1-(groupnum-1)/4;*/
+				if(cdf==1) step[4]=TESTSTEP;
+				
 				step[steptest]=0.0; step[steptest]=step[4]*steptest;
-				/*if(iteration>10)step[steptest]=0.015*steptest;
-				if(iteration>20)step[steptest]=0.01*steptest;
-				if(iteration>30) step[steptest]=0.005*steptest;
-				if(iteration>50) step[steptest]=0.003*steptest;*/
 				fprintf(FP,"step[%d]=%e",steptest,step[steptest]);
 				
 				if(MYID==0) fprintf(FI,"\n steptest %d: steplength=%e \n",steptest ,step[steptest]);
@@ -1109,7 +1105,7 @@ CPML_coeff(K_x,alpha_prime_x,a_x,b_x,K_x_half,alpha_prime_x_half,a_x_half,b_x_ha
 
 			if(MYID==0)fprintf(FP,"\n\n\n Steplength Parabel \n");
 			MPI_Barrier(MPI_COMM_WORLD);
-			steplength(misfit,step,iteration); /*find optimal steplength*/
+			steplength(misfit,step,iteration, it_group); /*find optimal steplength*/
 			}
 			
 			if(MYID==0)fprintf(FP,"\n Modelupdate \n");

src/steplength.c

@@ -23,17 +23,18 @@
  -------------------------------------------------------------*/
 
 #include "fd.h"
-void steplength(float *L2, float *step, int iteration){
+void steplength(float *L2, float *step, int iteration, int it_group){
 
 		extern FILE *FP;
 		extern FILE *FI;
-		extern int MYID;
+		extern int MYID, LBFGS;
 		extern float TESTSTEP;
 		float a=0.0, b=0.0, c=0.0;
 		float teststep=0.0;
   
 		teststep=TESTSTEP;
 		
+
 		if(MYID==0)fprintf(FP,"Start estimation of optimal steplength\n");
 		
 		/*calculation of the steplength parabola*/
@@ -61,9 +62,14 @@ void steplength(float *L2, float *step, int iteration){
 			if(MYID==0)fprintf(FP,"steplength larger stepmax, set to stepmax");
 		}
 		
+		if(LBFGS && it_group>1 && step[3]>1.0){
+			step[3]=1.0;
+			if(MYID==0)fprintf(FP,"steplength larger 1.0, set to 1.0");
+		}
+		
 		if(step[3]<=0){
 			 step[3]=0.1*step[1];
-			 if(MYID==0)fprintf(FP,"steplength smaller 0,  set to step[2]");
+			 if(MYID==0)fprintf(FP,"steplength smaller 0,  set to %e", step[3]);
 		}
 		
 		if(step[3]<0.1*step[1]){ step[3]=0.1*step[1];
@@ -79,7 +85,7 @@ void steplength(float *L2, float *step, int iteration){
 		
 		if(step[4]<0.2*teststep) step[4]=0.2*teststep;
 		if(step[4]>teststep) step[4]=teststep;
-		
+		if(LBFGS && it_group>1) step[4]=0.5;
 		if(MYID==0)fprintf(FI,"new test-steplength4: %e\n", step[4]);
 
 }