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diff --git a/src/boost/libs/math/example/policy_ref_snip11.cpp b/src/boost/libs/math/example/policy_ref_snip11.cpp
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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 approoximately 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 approoximately equivalent to 9 decimal digits
+ quantile(normal_distribution<double, policy<digits2<25> > >(), 0.05 = -1.64485363
+ */
+