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// Copyright John Maddock 2007.
// Copyright Paul A. Bristow 2010
// Use, modification and distribution are subject to the
// Boost Software License, Version 1.0. (See accompanying file
// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
// Note that this file contains quickbook mark-up as well as code
// and comments, don't change any of the special comment mark-ups!
#include <iostream>
using std::cout; using std::endl;
// Setting (approximate) precision 25 bits in a single function call using make_policy.
//[policy_ref_snip11
#include <boost/math/distributions/normal.hpp>
using boost::math::normal_distribution;
using namespace boost::math::policies;
const int bits = 25; // approximate precision.
double q = quantile(
normal_distribution<double, policy<digits2<bits> > >(),
0.05); // 5% quantile.
//] //[/policy_ref_snip11]
int main()
{
std::streamsize p = 2 + (bits * 30103UL) / 100000UL;
// Approximate number of significant decimal digits for 25 bits.
cout.precision(p);
cout << bits << " binary bits is approximately equivalent to " << p << " decimal digits " << endl;
cout << "quantile(normal_distribution<double, policy<digits2<25> > >(), 0.05 = "
<< q << endl; // -1.64485
}
/*
Output:
25 binary bits is approximately equivalent to 9 decimal digits
quantile(normal_distribution<double, policy<digits2<25> > >(), 0.05 = -1.64485363
*/
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