stability_th_cov.c

这个代码是tcl程序

#include<stdio.h>
#include<stdlib.h>
#include<math.h>

#define max_samples 10000
double cwnd[max_samples];
int sample_num;

#define resolution 1  /*number of samples per second*/
#define interval_num 6
int interval_duration[interval_num] = {1, 5, 10, 20, 40, 80}; /*unit: seoond*/

double flow_c2[interval_num];

double calculate_mean_within_interval(double* cwnd, int start, int num){
	double mean;
	int i;
	
	mean = 0;
	for(i=start;i<start+num;i++){
		mean += cwnd[i];
	}
	mean = mean/num;
	return mean;
}

double calculate_c2_per_flow_for_one_interval(double* cwnd, int total_num, int interval){
	double dd, mean, second_moment, c2;
	int num, i;

	mean = 0;
	second_moment = 0;
	num = 0;
	for(i=0;i<total_num;i=i+interval){
		if ((i+interval)<total_num) {
			dd = calculate_mean_within_interval(cwnd, i, interval);
		}else if ((total_num-i)>10) { /*less than 10 samples, then drop it*/
			dd = calculate_mean_within_interval(cwnd, i, total_num-i);
		}
		else
			break;
		mean += dd;
		second_moment += dd*dd;
		num++;
	}
	mean = mean/num;
	second_moment = second_moment/num;
	c2 = sqrt(second_moment-mean*mean)/mean;
	return c2;
}

void calculate_c2_per_flow_for_all_intervals(double* cwnd, int total_num){
	int i;

	for(i=0;i<interval_num;i++){
		flow_c2[i] += calculate_c2_per_flow_for_one_interval(cwnd, total_num, interval_duration[i]*resolution);
	}
}

void read_file(char* name, double* cwnd){
   char line[1024];
   float cwnd_time, cwnd_value;
   int i;
   FILE *file;

     file = fopen(name, "rt");
     if (file==0){
       printf("No file: %s\n", name);
       exit(-1);
     }
     sample_num = 0;
     while(!feof(file))
     {
       if (fgets(line, sizeof(line), file)==0)
         break;
       if (sscanf(line, "%f %f", &cwnd_time, &cwnd_value)==0)
         break;
	if(cwnd_time<200)
		continue;
       cwnd[sample_num] = cwnd_value;
       if (sample_num > max_samples) 
       {
	  printf("Please increase max_samples\n");
	  exit(-1);
       }
       sample_num++;
     }
     fclose(file);
}

void run(){
	char name[128];
	int i;
	
	for(i=0;i<interval_num;i++)
		flow_c2[i] = 0;
	for(i=0;i<4;i++){
		sprintf(name, "th_%i.out", i);
		read_file(name, cwnd);	
		calculate_c2_per_flow_for_all_intervals(cwnd, sample_num);
	}
	for(i=0;i<interval_num;i++){
		flow_c2[i] = flow_c2[i]/4;
		printf("%i %f\n", (i+1), flow_c2[i]);
	}
}

int main(){
	run();
}