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// Copyright Christopher Kormanyos 2013.
// Copyright Paul A. Bristow 2013.
// Copyright John Maddock 2013.
// Distributed under 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).
#ifdef _MSC_VER
# pragma warning (disable : 4512) // assignment operator could not be generated.
# pragma warning (disable : 4996) // assignment operator could not be generated.
#endif
#include <iostream>
#include <limits>
#include <vector>
#include <algorithm>
#include <iomanip>
#include <iterator>
//[neumann_zeros_example_1
/*`[h5 Calculating zeros of the Neumann function.]
This example also shows how Boost.Math and Boost.Multiprecision can be combined to provide
a many decimal digit precision. For 50 decimal digit precision we need to include
*/
#include <boost/multiprecision/cpp_dec_float.hpp>
/*`and a `typedef` for `float_type` may be convenient
(allowing a quick switch to re-compute at built-in `double` or other precision)
*/
typedef boost::multiprecision::cpp_dec_float_50 float_type;
//`To use the functions for finding zeros of the `cyl_neumann` function we need:
#include <boost/math/special_functions/bessel.hpp>
//] [/neumann_zerso_example_1]
int main()
{
try
{
{
//[neumann_zeros_example_2
/*`The Neumann (Bessel Y) function zeros are evaluated very similarly:
*/
using boost::math::cyl_neumann_zero;
double zn = cyl_neumann_zero(2., 1);
std::cout << "cyl_neumann_zero(2., 1) = " << zn << std::endl;
std::vector<float> nzeros(3); // Space for 3 zeros.
cyl_neumann_zero<float>(2.F, 1, nzeros.size(), nzeros.begin());
std::cout << "cyl_neumann_zero<float>(2.F, 1, ";
// Print the zeros to the output stream.
std::copy(nzeros.begin(), nzeros.end(),
std::ostream_iterator<float>(std::cout, ", "));
std::cout << "\n""cyl_neumann_zero(static_cast<float_type>(220)/100, 1) = "
<< cyl_neumann_zero(static_cast<float_type>(220)/100, 1) << std::endl;
// 3.6154383428745996706772556069431792744372398748422
//] //[/neumann_zeros_example_2]
}
}
catch (std::exception const& ex)
{
std::cout << "Thrown exception " << ex.what() << std::endl;
}
} // int main()
/*
Output:
cyl_neumann_zero(2., 1) = 3.38424
cyl_neumann_zero<float>(2.F, 1,
3.38424
6.79381
10.0235
3.61544
*/
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