41 lines
1.2 KiB
C++
41 lines
1.2 KiB
C++
// Copyright John Maddock 2007.
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// Copyright Paul A. Bristow 2010
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// Use, modification and distribution are subject to the
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// Boost Software License, Version 1.0. (See accompanying file
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// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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// Note that this file contains quickbook mark-up as well as code
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// and comments, don't change any of the special comment mark-ups!
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double some_value = 2.;
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//[policy_ref_snip3
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#include <boost/math/special_functions/gamma.hpp>
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using namespace boost::math::policies;
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using boost::math::tgamma;
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// Define a new policy *not* internally promoting RealType to double:
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typedef policy<
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promote_double<false>
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> my_policy;
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// Call the function, applying the new policy:
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double t1 = tgamma(some_value, my_policy());
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// Alternatively we could use helper function make_policy,
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// and concisely define everything at the call site:
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double t2 = tgamma(some_value, make_policy(promote_double<false>()));
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//] //[\policy_ref_snip3]
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#include <iostream>
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using std::cout; using std::endl;
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int main()
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{
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cout << "tgamma(some_value, my_policy()) = " << t1
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<< ", tgamma(some_value, make_policy(promote_double<false>()) = " << t2 << endl;
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}
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