"Dave Sill" <[EMAIL PROTECTED]> wrote:
>--IPiIw4QAe+
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>etc.
Argh. Forgot about my Emacs' broken MIME. Here's the program:
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
main(int argc, char **argv)
{
int hash[10000], i;
int size=16, reps=100000000, seed=0;
long j;
float mean, variance=0, stddev;
if (argc >= 2) {
sscanf (argv[1], "%d", &size);
if (size > 10000)
exit (1);
}
if (argc >= 3)
sscanf (argv[2], "%d", &reps);
if (argc >= 4)
sscanf (argv[3], "%d", &seed);
mean=reps/size;
printf ("size=%d, reps=%d, seed=%d\n", size, reps, seed);
for (i=0; i<size; i++) {
hash[i]=0;
}
srand48 (seed);
for (i=0; i<reps; i++) {
j=lrand48();
hash[j%size]++;
}
for (i=0; i<size; i++) {
printf ("%d: %d\n", i, hash[i]);
variance += pow(hash[i] - mean, 2.0);
}
variance /= (float)size-1;
stddev=sqrt(variance);
printf ("mean=%f, variance=%f\n", mean, variance);
printf ("stddev=%f (%f%)\n", stddev, stddev/mean*100);
}
-Dave
