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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 14:18:53 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 14:18:53 +0000
commita0e0018c9a7ef5ce7f6d2c3ae16aecbbd16a8f67 (patch)
tree8feaf1a1932871b139b3b30be4c09c66489918be /netem/stats.c
parentInitial commit. (diff)
downloadiproute2-upstream.tar.xz
iproute2-upstream.zip
Adding upstream version 6.1.0.upstream/6.1.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'netem/stats.c')
-rw-r--r--netem/stats.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/netem/stats.c b/netem/stats.c
new file mode 100644
index 0000000..ed70f16
--- /dev/null
+++ b/netem/stats.c
@@ -0,0 +1,77 @@
+/*
+ * Experimental data distribution table generator
+ * Taken from the uncopyrighted NISTnet code (public domain).
+ *
+ * Rread in a series of "random" data values, either
+ * experimentally or generated from some probability distribution.
+ * From this, report statistics.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <malloc.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+void
+stats(FILE *fp)
+{
+ struct stat info;
+ double *x;
+ int limit;
+ int n=0, i;
+ double mu=0.0, sigma=0.0, sumsquare=0.0, sum=0.0, top=0.0, rho=0.0;
+ double sigma2=0.0;
+
+ fstat(fileno(fp), &info);
+ if (info.st_size > 0) {
+ limit = 2*info.st_size/sizeof(double); /* @@ approximate */
+ } else {
+ limit = 10000;
+ }
+ x = (double *)malloc(limit*sizeof(double));
+
+ for (i=0; i<limit; ++i){
+ fscanf(fp, "%lf", &x[i]);
+ if (feof(fp))
+ break;
+ sumsquare += x[i]*x[i];
+ sum += x[i];
+ ++n;
+ }
+ mu = sum/(double)n;
+ sigma = sqrt((sumsquare - (double)n*mu*mu)/(double)(n-1));
+
+ for (i=1; i < n; ++i){
+ top += ((double)x[i]-mu)*((double)x[i-1]-mu);
+ sigma2 += ((double)x[i-1] - mu)*((double)x[i-1] - mu);
+
+ }
+ rho = top/sigma2;
+
+ printf("mu = %12.6f\n", mu);
+ printf("sigma = %12.6f\n", sigma);
+ printf("rho = %12.6f\n", rho);
+ /*printf("sigma2 = %10.4f\n", sqrt(sigma2/(double)(n-1)));*/
+ /*printf("correlation rho = %10.6f\n", top/((double)(n-1)*sigma*sigma));*/
+}
+
+
+int
+main(int argc, char **argv)
+{
+ FILE *fp;
+
+ if (argc > 1) {
+ fp = fopen(argv[1], "r");
+ if (!fp) {
+ perror(argv[1]);
+ exit(1);
+ }
+ } else {
+ fp = stdin;
+ }
+ stats(fp);
+ return 0;
+}