/* Web Polygraph       http://www.web-polygraph.org/
 * (C) 2003-2006 The Measurement Factory
 * Licensed under the Apache License, Version 2.0 */

#include "pgl/pgl.h"

#include "xstd/h/math.h"
#include "xstd/h/iostream.h"

#include "xstd/Rnd.h"
#include "pgl/popDistrs.h"


/* UnifPopDistr */

int UnifPopDistr::choose(RndGen &rng, int lastOid) {
	return 1 + rng(0, lastOid);
}

ostream &UnifPopDistr::print(ostream &os) const {
	return os << "popUnif()";
}


/* ZipfPopDistr */

ZipfPopDistr::ZipfPopDistr(double aSkew): theSkew(aSkew) {
}

int ZipfPopDistr::choose(RndGen &rng, int lastOid) {
	const double rn = rng();
	return 1 + lastOid - (int)pow(lastOid+1, pow(rn,theSkew));
}

ostream &ZipfPopDistr::print(ostream &os) const {
	return os << "popZipf(" << theSkew << ')';
}