/*We use the Cauchy Gourat theorem to compute the derivatives of the double(Mellin+Laplace) transform */
static dcomplex dermellin(dcomplex l, double sg, double r, int nummom)
{
dcomplex term, cv, mu;
int i;
double r0,sumr, sumi/*,x[NPOINTS_FUSAITAGL+1],w[NPOINTS_FUSAITAGL+1]*/;
double v;
double *x,*w;
x=malloc((NPOINTS_FUSAITAGL+1)*sizeof(double));
w=malloc((NPOINTS_FUSAITAGL+1)*sizeof(double));
sumr=0.0;
sumi=0.0;
gauleg(0, 2*M_PI, x, w,NPOINTS_FUSAITAGL);
v = 2*r/(sg*sg)-1.0;
cv = Complex(v,0.0);
mu = Csqrt(Cadd(Complex(v*v,0), RCmul(2.0,l)));
r0 = Creal(RCmul(0.5,Csub(mu,cv)));
if(r0>1.0) r0=0.25;
for (i=1;i<=NPOINTS_FUSAITAGL;i++)
{
term = RCmul(pow(r0,nummom), Cexp(Complex(0.0, nummom*x[i])));
sumr += w[i]*Creal(Cdiv(mellintransform(l, RCmul(r0, Cexp(Complex(0.0, x[i]))), sg, r), term));
sumi += w[i]*Cimag(Cdiv(mellintransform(l, RCmul(r0, Cexp(Complex(0.0, x[i]))), sg, r), term));
}
free(x);
free(w);
return Complex(exp(factln(nummom))*sumr/(2.0*M_PI),exp(factln(nummom))*sumi/(2.0*M_PI));
}
float bico(int n, int k)
/*returns the binomial coefficient Cn(haut)k(bas) = n!/(k!(n-k)!) as a floating-
point number*/
{
float factln(int n);
return (float)floor(0.5+exp(factln(n)-factln(k)-factln(n-k)));
}
arma::mat factln(const arma::imat& x) {
arma::mat ans; ans.copy_size(x);
for(size_t i = 0; i < x.n_elem; i++) {
ans[i] = factln(x[i]);
}
return ans;
}
double bino_pdf(int k, int n, float p)
{
double ln_binco = factln(n)-factln(k)-factln(n-k);
double ln_ret = ln_binco + k*log(p) + (n-k)*log(1-p);
return exp(ln_ret);
}
//funcao log-choose
double Lchoose(int n, int k){
return(factln(n) - factln(k) - factln((n) - (k)));
}
template<> template<typename eT> arma_hot arma_pure arma_inline eT
eop_core<eop_factln>::process(const eT val, const eT ) {
return factln(val);
}
/**
* Compute the binomial coefficient (n,k)
* Taken from numerical recipes.
**/
inline double bico(const int64 n, const int64 k)
{
MTOOLS_ASSERT((n >= 0) || (k >= 0) || (k <= n));
if (n < 171) return floor(0.5 + factrl(n) / (factrl(k)*factrl(n - k)));
return floor(0.5 + exp(factln(n) - factln(k) - factln(n - k)));
}
double bico(int n, int k)
{
double factln(int n);
return floor(0.5+exp(factln(n)-factln(k)-factln(n-k)));
}
float bico(int n, int k) // returns binomial coefficients (nCk)
{
if (k == 1) return n;
if (k == 0) return 1.0;
else return floor(0.5+exp(factln(n)-factln(k)-factln(n-k)));
}
/* function bico(int n, int k)
* ----------------------------
* Binomial coefficient
*/
REAL_TYPE bico(int n, int k)
{
return std::floor(0.5+std::exp(factln(n)-factln(k)-factln(n-k)));
}
float bico(int n, int k) {
return floor(0.5+exp(factln(n)-factln(k)-factln(n-k)));
}
