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			66 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			66 lines
		
	
	
		
			1.8 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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| 
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| #include <iostream>
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| using std::cout; using std::endl;
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| #include <cerrno> // for ::errno
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| 
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| //[policy_eg_2
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| 
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| #include <boost/math/special_functions/gamma.hpp>
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| using boost::math::tgamma;
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| 
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| int main()
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| {
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|    // using namespace boost::math::policies; // or
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|    using boost::math::policies::errno_on_error;
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|    using boost::math::policies::make_policy;
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|    using boost::math::policies::pole_error;
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|    using boost::math::policies::domain_error;
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|    using boost::math::policies::overflow_error;
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|    using boost::math::policies::evaluation_error;
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| 
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|    errno = 0;
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|    std::cout << "Result of tgamma(30000) is: " 
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|       << boost::math::tgamma(
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|          30000, 
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|          make_policy(
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|             domain_error<errno_on_error>(),
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|             pole_error<errno_on_error>(),
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|             overflow_error<errno_on_error>(),
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|             evaluation_error<errno_on_error>() 
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|          )
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|       ) << std::endl;
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|    // Check errno was set:
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|    std::cout << "errno = " << errno << std::endl;
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|    // and again with evaluation at a pole:
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|    std::cout << "Result of tgamma(-10) is: " 
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|       << boost::math::tgamma(
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|          -10, 
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|          make_policy(
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|             domain_error<errno_on_error>(),
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|             pole_error<errno_on_error>(),
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|             overflow_error<errno_on_error>(),
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|             evaluation_error<errno_on_error>() 
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|          )
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|       ) << std::endl;
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|    // Check errno was set:
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|    std::cout << "errno = " << errno << std::endl;
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| }
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| 
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| //] //[/policy_eg_2]
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| 
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| /*
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| 
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| Output:
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| 
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|   Result of tgamma(30000) is: 1.#INF
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|   errno = 34
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|   Result of tgamma(-10) is: 1.#QNAN
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|   errno = 33
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| */
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| 
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