llvm/libcxx/test/std/numerics/rand/rand.dist/rand.dist.samp/rand.dist.samp.pconst/param_ctor_iterator.pass.cpp

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// <random>

// template<class RealType = double>
// class piecewise_constant_distribution

// template<class InputIterator>
//     param_type(InputIteratorB firstB, InputIteratorB lastB,
//                InputIteratorW firstW);

#include <random>

#include <cassert>
#include <vector>

#include "test_macros.h"

int main(int, char**)
{
    {
        typedef std::piecewise_constant_distribution<> D;
        typedef D::param_type P;
        double b[] = {10};
        double p[] = {12};
        P pa(b, b, p);
        std::vector<double> iv = pa.intervals();
        assert(iv.size() == 2);
        assert(iv[0] == 0);
        assert(iv[1] == 1);
        std::vector<double> dn = pa.densities();
        assert(dn.size() == 1);
        assert(dn[0] == 1);
    }
    {
        typedef std::piecewise_constant_distribution<> D;
        typedef D::param_type P;
        double b[] = {10};
        double p[] = {12};
        P pa(b, b+1, p);
        std::vector<double> iv = pa.intervals();
        assert(iv.size() == 2);
        assert(iv[0] == 0);
        assert(iv[1] == 1);
        std::vector<double> dn = pa.densities();
        assert(dn.size() == 1);
        assert(dn[0] == 1);
    }
    {
        typedef std::piecewise_constant_distribution<> D;
        typedef D::param_type P;
        double b[] = {10, 15};
        double p[] = {12};
        P pa(b, b+2, p);
        std::vector<double> iv = pa.intervals();
        assert(iv.size() == 2);
        assert(iv[0] == 10);
        assert(iv[1] == 15);
        std::vector<double> dn = pa.densities();
        assert(dn.size() == 1);
        assert(dn[0] == 1/5.);
    }
    {
        typedef std::piecewise_constant_distribution<> D;
        typedef D::param_type P;
        double b[] = {10, 15, 16};
        double p[] = {.25, .75};
        P pa(b, b+3, p);
        std::vector<double> iv = pa.intervals();
        assert(iv.size() == 3);
        assert(iv[0] == 10);
        assert(iv[1] == 15);
        assert(iv[2] == 16);
        std::vector<double> dn = pa.densities();
        assert(dn.size() == 2);
        assert(dn[0] == .25/5.);
        assert(dn[1] == .75);
    }
    {
        typedef std::piecewise_constant_distribution<> D;
        typedef D::param_type P;
        double b[] = {10, 14, 16, 17};
        double p[] = {25, 62.5, 12.5};
        P pa(b, b+4, p);
        std::vector<double> iv = pa.intervals();
        assert(iv.size() == 4);
        assert(iv[0] == 10);
        assert(iv[1] == 14);
        assert(iv[2] == 16);
        assert(iv[3] == 17);
        std::vector<double> dn = pa.densities();
        assert(dn.size() == 3);
        assert(dn[0] == .0625);
        assert(dn[1] == .3125);
        assert(dn[2] == .125);
    }

  return 0;
}