Problem - Kevin Tafuro

In all cases, we start with a number with uniform distribution using the API from
Recipe 11.12.
Note that these functions use math operations defined in the standard math library.
On many platforms, you will have to link against the appropriate library (usually by
adding -lm to your link line).
#include
#define NVCONST 1.7155277699141
double spc_rand_normalvariate(double mu, double sigma) {
double myr1, myr2, t1, t2;
do {
myr1 = spc_rand_real( );
myr2 = spc_rand_real( );
t1 = NVCONST * (myr1 - 0.5) / myr2;
t2 = t1 * t1 / 4.0;
} while (t2 > -log(myr2));
return mu + t1 * sigma;
}
double spc_rand_lognormalvariate(double mu, double sigma) {
return exp(spc_rand_normalvariate(mu, sigma));
}
double spc_rand_paretovariate(double alpha) {
return 1.0 / pow(spc_rand_real( ), 1.0 / alpha);
}
double spc_rand_weibullvariate(double alpha, double beta) {
return alpha * pow(-log(spc_rand_real( )), 1.0 / beta);
}
double spc_rand_expovariate(double lambda) {
double myr = spc_rand_real( );
while (myr