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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!
double some_value = 2.;
//[policy_ref_snip3
#include <boost/math/special_functions/gamma.hpp>
using namespace boost::math::policies;
using boost::math::tgamma;
// Define a new policy *not* internally promoting RealType to double:
typedef policy<
promote_double<false>
> my_policy;
// Call the function, applying the new policy:
double t1 = tgamma(some_value, my_policy());
// Alternatively we could use helper function make_policy,
// and concisely define everything at the call site:
double t2 = tgamma(some_value, make_policy(promote_double<false>()));
//] //[\policy_ref_snip3]
#include <iostream>
using std::cout; using std::endl;
int main()
{
cout << "tgamma(some_value, my_policy()) = " << t1
<< ", tgamma(some_value, make_policy(promote_double<false>()) = " << t2 << endl;
}
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