Very basic empirical distribution (for unordered data).

emperical_dist.cpp

#include "stdafx.h"
#include "emperical_dist.h"

void emperical_dist(double* vals, double* res, int* vlen, int* dlen) {
	int i, j, tmp, n = *vlen;
	double *valsAt, val; 
	for(i=0; i<*dlen; ++i, ++res){
		valsAt = vals;
		val = *res;
		tmp = 0;
		for(j=0; j<n; ++j, ++valsAt) if(*valsAt <= val) ++tmp;
		*res = (double)tmp / (double)n;
	}
}