void randirichlet(double *x, double *pp, int n)
/**
generate dirichlet r.v. parameters pp
*/
{
double y ;
int i ;
for (i=0; i<n; i++) {
x[i] = rangam(pp[i]) ;
}
bal1(x,n) ;
}
void randirichlet(double *x, double *pp, int n)
/**
generate dirichlet r.v. parameters pp
*/
{
int i ;
vzero(x, n) ;
for (i=0; i<n; i++) {
if (pp[i] > 0.0) {
x[i] = rangam(pp[i]) ;
}
}
bal1(x,n) ;
}
void ranmultinom(int *samp, int n, double *p, int len)
// multinomial sample p is prob dist n samples returned
// work is O(len^2) which is silly
{
int x ;
double *pp ;
if (len==0) return ;
ivzero(samp, len) ;
if (n<=0) return ;
if (len==1) {
samp[0] = n ;
return ;
}
ZALLOC(pp, len, double) ;
copyarr(p, pp, len) ;
bal1(pp, len) ;
samp[0] = x = ranbinom(n, pp[0]) ;
ranmultinom(samp+1, n-x, p+1, len-1) ;
free(pp) ;
}
