X-Git-Url: https://hackdaworld.org/gitweb/?a=blobdiff_plain;f=moldyn.c;h=4c43f2e1641dbd2a35bfab5f9ffdc78243d9c6b2;hb=b776d78d5fe14e550e2b4a51a2b837742ed6f850;hp=c130ef442b838175272e62f375daa4fbaa8e199b;hpb=f60d78f7f3243120dc284f9c089849e610f9ec0f;p=physik%2Fposic.git

diff --git a/moldyn.c b/moldyn.c
index c130ef4..4c43f2e 100644
--- a/moldyn.c
+++ b/moldyn.c
@@ -1838,6 +1838,7 @@ int calc_fluctuations(double start,double end,t_moldyn *moldyn) {
 	int count,ret;
 	double time,pot,kin,tot;
 	double p_sum,k_sum,t_sum;
+	double p2_sum,k2_sum,t2_sum;
 	char buf[64];
 	char file[128+7];
 
@@ -1850,7 +1851,7 @@ int calc_fluctuations(double start,double end,t_moldyn *moldyn) {
 		return fd;
 	}
 
-	/* first calc the averages */
+	/* calc the averages of A and A^2 */
 	p_sum=0.0;
 	k_sum=0.0;
 	t_sum=0.0;
@@ -1865,38 +1866,21 @@ int calc_fluctuations(double start,double end,t_moldyn *moldyn) {
 		p_sum+=pot;
 		k_sum+=kin;
 		t_sum+=tot;
+		p2_sum+=(pot*pot);
+		k2_sum+=(kin*kin);
+		t2_sum+=(tot*tot);
 		count+=1;
 	}
 
-	moldyn->p_m=p_sum/count;
+	/* averages */
 	moldyn->k_m=k_sum/count;
+	moldyn->p_m=p_sum/count;
 	moldyn->t_m=t_sum/count;
 
-	/* mean square fluctuations */
-	if(lseek(fd,SEEK_SET,0)<0) {
-		perror("[moldyn] lseek");
-		return -1;
-	}
-	count=0;
-	p_sum=0.0;
-	k_sum=0.0;
-	t_sum=0.0;
-	while(1) {
-		ret=get_line(fd,buf,63);
-		if(ret<=0) break;
-		if(buf[0]=='#') continue;
-		sscanf(buf,"%lf %lf %lf %lf",&time,&kin,&pot,&tot);
-		if(time<start) continue;
-		if(time>end) break;
-		k_sum+=((kin-moldyn->k_m)*(kin-moldyn->k_m));
-		p_sum+=((pot-moldyn->p_m)*(pot-moldyn->p_m));
-		t_sum+=((tot-moldyn->t_m)*(tot-moldyn->t_m));
-		count+=1;
-	}
-
-	moldyn->dp2_m=p_sum/count;
-	moldyn->dk2_m=k_sum/count;
-	moldyn->dt2_m=t_sum/count;
+	/* rms */
+	moldyn->dk2_m=k2_sum/count-moldyn->k_m*moldyn->k_m;
+	moldyn->dp2_m=p2_sum/count-moldyn->p_m*moldyn->p_m;
+	moldyn->dt2_m=t2_sum/count-moldyn->t_m*moldyn->t_m;
 
 	printf("  averages   : %f %f %f\n",moldyn->k_m,
 	                                moldyn->p_m,