/* * Normal distribution table generator * Taken from the uncopyrighted NISTnet code. */ #include <stdio.h> #include <stdlib.h> #include <math.h> #include <string.h> #include <limits.h> #include <linux/types.h> #include <linux/pkt_sched.h> #define TABLESIZE 16384 #define TABLEFACTOR NETEM_DIST_SCALE static double normal(double x, double mu, double sigma) { return .5 + .5*erf((x-mu)/(sqrt(2.0)*sigma)); } int main(int argc, char **argv) { int i, n; double x; double table[TABLESIZE+1]; for (x = -10.0; x < 10.05; x += .00005) { i = rint(TABLESIZE * normal(x, 0.0, 1.0)); table[i] = x; } printf("# This is the distribution table for the normal distribution.\n"); for (i = n = 0; i < TABLESIZE; i += 4) { int value = (int) rint(table[i]*TABLEFACTOR); if (value < SHRT_MIN) value = SHRT_MIN; if (value > SHRT_MAX) value = SHRT_MAX; printf(" %d", value); if (++n == 8) { putchar('\n'); n = 0; } } return 0; }