summaryrefslogtreecommitdiffstats
path: root/src/boost/libs/math/example/root_elliptic_finding.cpp
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 18:24:20 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 18:24:20 +0000
commit483eb2f56657e8e7f419ab1a4fab8dce9ade8609 (patch)
treee5d88d25d870d5dedacb6bbdbe2a966086a0a5cf /src/boost/libs/math/example/root_elliptic_finding.cpp
parentInitial commit. (diff)
downloadceph-upstream.tar.xz
ceph-upstream.zip
Adding upstream version 14.2.21.upstream/14.2.21upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/boost/libs/math/example/root_elliptic_finding.cpp')
-rw-r--r--src/boost/libs/math/example/root_elliptic_finding.cpp878
1 files changed, 878 insertions, 0 deletions
diff --git a/src/boost/libs/math/example/root_elliptic_finding.cpp b/src/boost/libs/math/example/root_elliptic_finding.cpp
new file mode 100644
index 00000000..a1c81124
--- /dev/null
+++ b/src/boost/libs/math/example/root_elliptic_finding.cpp
@@ -0,0 +1,878 @@
+// Copyright Paul A. Bristow 2015
+
+// 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)
+
+// Comparison of finding roots using TOMS748, Newton-Raphson, Halley & Schroder algorithms.
+// root_n_finding_algorithms.cpp Generalised for nth root version.
+
+// http://en.wikipedia.org/wiki/Cube_root
+
+// Note that this file contains Quickbook mark-up as well as code
+// and comments, don't change any of the special comment mark-ups!
+// This program also writes files in Quickbook tables mark-up format.
+
+#include <boost/cstdlib.hpp>
+#include <boost/config.hpp>
+#include <boost/array.hpp>
+#include <boost/type_traits/is_floating_point.hpp>
+#include <boost/math/tools/roots.hpp>
+#include <boost/math/special_functions/ellint_1.hpp>
+#include <boost/math/special_functions/ellint_2.hpp>
+
+//using boost::math::policies::policy;
+//using boost::math::tools::eps_tolerance; // Binary functor for specified number of bits.
+//using boost::math::tools::bracket_and_solve_root;
+//using boost::math::tools::toms748_solve;
+//using boost::math::tools::halley_iterate;
+//using boost::math::tools::newton_raphson_iterate;
+//using boost::math::tools::schroder_iterate;
+
+#include <boost/math/special_functions/next.hpp> // For float_distance.
+
+#include <boost/multiprecision/cpp_bin_float.hpp> // is binary.
+using boost::multiprecision::cpp_bin_float_100;
+using boost::multiprecision::cpp_bin_float_50;
+
+#include <boost/timer/timer.hpp>
+#include <boost/system/error_code.hpp>
+#include <boost/preprocessor/stringize.hpp>
+
+// STL
+#include <iostream>
+#include <iomanip>
+#include <string>
+#include <vector>
+#include <limits>
+#include <fstream> // std::ofstream
+#include <cmath>
+#include <typeinfo> // for type name using typid(thingy).name();
+
+#ifdef __FILE__
+ std::string sourcefilename = __FILE__;
+#else
+ std::string sourcefilename("");
+#endif
+
+ std::string chop_last(std::string s)
+ {
+ std::string::size_type pos = s.find_last_of("\\/");
+ if(pos != std::string::npos)
+ s.erase(pos);
+ else if(s.empty())
+ abort();
+ else
+ s.erase();
+ return s;
+ }
+
+ std::string make_root()
+ {
+ std::string result;
+ if(sourcefilename.find_first_of(":") != std::string::npos)
+ {
+ result = chop_last(sourcefilename); // lose filename part
+ result = chop_last(result); // lose /example/
+ result = chop_last(result); // lose /math/
+ result = chop_last(result); // lose /libs/
+ }
+ else
+ {
+ result = chop_last(sourcefilename); // lose filename part
+ if(result.empty())
+ result = ".";
+ result += "/../../..";
+ }
+ return result;
+ }
+
+ std::string short_file_name(std::string s)
+ {
+ std::string::size_type pos = s.find_last_of("\\/");
+ if(pos != std::string::npos)
+ s.erase(0, pos + 1);
+ return s;
+ }
+
+ std::string boost_root = make_root();
+
+
+std::string fp_hardware; // Any hardware features like SEE or AVX
+
+const std::string roots_name = "libs/math/doc/roots/";
+
+const std::string full_roots_name(boost_root + "/libs/math/doc/roots/");
+
+const std::size_t nooftypes = 4;
+const std::size_t noofalgos = 4;
+
+double digits_accuracy = 1.0; // 1 == maximum possible accuracy.
+
+std::stringstream ss;
+
+std::ofstream fout;
+
+std::vector<std::string> algo_names =
+{
+ "TOMS748", "Newton", "Halley", "Schr'''&#xf6;'''der"
+};
+
+std::vector<std::string> names =
+{
+ "float", "double", "long double", "cpp_bin_float50"
+};
+
+uintmax_t iters; // Global as value of iterations is not returned.
+
+struct root_info
+{ // for a floating-point type, float, double ...
+ std::size_t max_digits10; // for type.
+ std::string full_typename; // for type from type_id.name().
+ std::string short_typename; // for type "float", "double", "cpp_bin_float_50" ....
+ std::size_t bin_digits; // binary in floating-point type numeric_limits<T>::digits;
+ int get_digits; // fraction of maximum possible accuracy required.
+ // = digits * digits_accuracy
+ // Vector of values (4) for each algorithm, TOMS748, Newton, Halley & Schroder.
+ //std::vector< boost::int_least64_t> times; converted to int.
+ std::vector<int> times; // arbirary units (ticks).
+ //boost::int_least64_t min_time = std::numeric_limits<boost::int_least64_t>::max(); // Used to normalize times (as int).
+ std::vector<double> normed_times;
+ int min_time = (std::numeric_limits<int>::max)(); // Used to normalize times.
+ std::vector<uintmax_t> iterations;
+ std::vector<long int> distances;
+ std::vector<cpp_bin_float_100> full_results;
+}; // struct root_info
+
+std::vector<root_info> root_infos; // One element for each floating-point type used.
+
+inline std::string build_test_name(const char* type_name, const char* test_name)
+{
+ std::string result(BOOST_COMPILER);
+ result += "|";
+ result += BOOST_STDLIB;
+ result += "|";
+ result += BOOST_PLATFORM;
+ result += "|";
+ result += type_name;
+ result += "|";
+ result += test_name;
+#if defined(_DEBUG) || !defined(NDEBUG)
+ result += "|";
+ result += " debug";
+#else
+ result += "|";
+ result += " release";
+#endif
+ result += "|";
+ return result;
+} // std::string build_test_name
+
+// Algorithms //////////////////////////////////////////////
+
+// No derivatives - using TOMS748 internally.
+//[elliptic_noderv_func
+template <typename T = double>
+struct elliptic_root_functor_noderiv
+{ // Nth root of x using only function - no derivatives.
+ elliptic_root_functor_noderiv(T const& arc, T const& radius) : m_arc(arc), m_radius(radius)
+ { // Constructor just stores value a to find root of.
+ }
+ T operator()(T const& x)
+ {
+ using std::sqrt;
+ // return the difference between required arc-length, and the calculated arc-length for an
+ // ellipse with radii m_radius and x:
+ T a = (std::max)(m_radius, x);
+ T b = (std::min)(m_radius, x);
+ T k = sqrt(1 - b * b / (a * a));
+ return 4 * a * boost::math::ellint_2(k) - m_arc;
+ }
+private:
+ T m_arc; // length of arc.
+ T m_radius; // one of the two radii of the ellipse
+}; // template <class T> struct elliptic_root_functor_noderiv
+//]
+//[elliptic_root_noderiv
+template <class T = double>
+T elliptic_root_noderiv(T radius, T arc)
+{ // return the other radius of an ellipse, given one radii and the arc-length
+ using namespace std; // Help ADL of std functions.
+ using namespace boost::math::tools; // For bracket_and_solve_root.
+
+ T guess = sqrt(arc * arc / 16 - radius * radius);
+ T factor = 1.2; // How big steps to take when searching.
+
+ const boost::uintmax_t maxit = 50; // Limit to maximum iterations.
+ boost::uintmax_t it = maxit; // Initally our chosen max iterations, but updated with actual.
+ bool is_rising = true; // arc-length increases if one radii increases, so function is rising
+ // Define a termination condition, stop when nearly all digits are correct, but allow for
+ // the fact that we are returning a range, and must have some inaccuracy in the elliptic integral:
+ eps_tolerance<T> tol(std::numeric_limits<T>::digits - 2);
+ // Call bracket_and_solve_root to find the solution, note that this is a rising function:
+ std::pair<T, T> r = bracket_and_solve_root(elliptic_root_functor_noderiv<T>(arc, radius), guess, factor, is_rising, tol, it);
+ //<-
+ iters = it;
+ //->
+ // Result is midway between the endpoints of the range:
+ return r.first + (r.second - r.first) / 2;
+} // template <class T> T elliptic_root_noderiv(T x)
+//]
+// Using 1st derivative only Newton-Raphson
+//[elliptic_1deriv_func
+template <class T = double>
+struct elliptic_root_functor_1deriv
+{ // Functor also returning 1st derviative.
+ BOOST_STATIC_ASSERT_MSG(boost::is_integral<T>::value == false, "Only floating-point type types can be used!");
+
+ elliptic_root_functor_1deriv(T const& arc, T const& radius) : m_arc(arc), m_radius(radius)
+ { // Constructor just stores value a to find root of.
+ }
+ std::pair<T, T> operator()(T const& x)
+ {
+ using std::sqrt;
+ // Return the difference between required arc-length, and the calculated arc-length for an
+ // ellipse with radii m_radius and x, plus it's derivative.
+ // See http://www.wolframalpha.com/input/?i=d%2Fda+[4+*+a+*+EllipticE%281+-+b^2%2Fa^2%29]
+ // We require two elliptic integral calls, but from these we can calculate both
+ // the function and it's derivative:
+ T a = (std::max)(m_radius, x);
+ T b = (std::min)(m_radius, x);
+ T a2 = a * a;
+ T b2 = b * b;
+ T k = sqrt(1 - b2 / a2);
+ T Ek = boost::math::ellint_2(k);
+ T Kk = boost::math::ellint_1(k);
+ T fx = 4 * a * Ek - m_arc;
+ T dfx = 4 * (a2 * Ek - b2 * Kk) / (a2 - b2);
+ return std::make_pair(fx, dfx);
+ }
+private:
+ T m_arc; // length of arc.
+ T m_radius; // one of the two radii of the ellipse
+}; // struct elliptic_root__functor_1deriv
+//]
+//[elliptic_1deriv
+template <class T = double>
+T elliptic_root_1deriv(T radius, T arc)
+{
+ using namespace std; // Help ADL of std functions.
+ using namespace boost::math::tools; // For newton_raphson_iterate.
+
+ BOOST_STATIC_ASSERT_MSG(boost::is_integral<T>::value == false, "Only floating-point type types can be used!");
+
+ T guess = sqrt(arc * arc / 16 - radius * radius);
+ T min = 0; // Minimum possible value is zero.
+ T max = arc; // Maximum possible value is the arc length.
+
+ // Accuracy doubles at each step, so stop when just over half of the digits are
+ // correct, and rely on that step to polish off the remainder:
+ int get_digits = static_cast<int>(std::numeric_limits<T>::digits * 0.6);
+ const boost::uintmax_t maxit = 20;
+ boost::uintmax_t it = maxit;
+ T result = newton_raphson_iterate(elliptic_root_functor_1deriv<T>(arc, radius), guess, min, max, get_digits, it);
+ //<-
+ iters = it;
+ //->
+ return result;
+} // T elliptic_root_1_deriv Newton-Raphson
+//]
+
+// Using 1st and 2nd derivatives with Halley algorithm.
+//[elliptic_2deriv_func
+template <class T = double>
+struct elliptic_root_functor_2deriv
+{ // Functor returning both 1st and 2nd derivatives.
+ BOOST_STATIC_ASSERT_MSG(boost::is_integral<T>::value == false, "Only floating-point type types can be used!");
+
+ elliptic_root_functor_2deriv(T const& arc, T const& radius) : m_arc(arc), m_radius(radius) {}
+ std::tuple<T, T, T> operator()(T const& x)
+ {
+ using std::sqrt;
+ // Return the difference between required arc-length, and the calculated arc-length for an
+ // ellipse with radii m_radius and x, plus it's derivative.
+ // See http://www.wolframalpha.com/input/?i=d^2%2Fda^2+[4+*+a+*+EllipticE%281+-+b^2%2Fa^2%29]
+ // for the second derivative.
+ T a = (std::max)(m_radius, x);
+ T b = (std::min)(m_radius, x);
+ T a2 = a * a;
+ T b2 = b * b;
+ T k = sqrt(1 - b2 / a2);
+ T Ek = boost::math::ellint_2(k);
+ T Kk = boost::math::ellint_1(k);
+ T fx = 4 * a * Ek - m_arc;
+ T dfx = 4 * (a2 * Ek - b2 * Kk) / (a2 - b2);
+ T dfx2 = 4 * b2 * ((a2 + b2) * Kk - 2 * a2 * Ek) / (a * (a2 - b2) * (a2 - b2));
+ return std::make_tuple(fx, dfx, dfx2);
+ }
+private:
+ T m_arc; // length of arc.
+ T m_radius; // one of the two radii of the ellipse
+};
+//]
+//[elliptic_2deriv
+template <class T = double>
+T elliptic_root_2deriv(T radius, T arc)
+{
+ using namespace std; // Help ADL of std functions.
+ using namespace boost::math::tools; // For halley_iterate.
+
+ BOOST_STATIC_ASSERT_MSG(boost::is_integral<T>::value == false, "Only floating-point type types can be used!");
+
+ T guess = sqrt(arc * arc / 16 - radius * radius);
+ T min = 0; // Minimum possible value is zero.
+ T max = arc; // radius can't be larger than the arc length.
+
+ // Accuracy triples at each step, so stop when just over one-third of the digits
+ // are correct, and the last iteration will polish off the remaining digits:
+ int get_digits = static_cast<int>(std::numeric_limits<T>::digits * 0.4);
+ const boost::uintmax_t maxit = 20;
+ boost::uintmax_t it = maxit;
+ T result = halley_iterate(elliptic_root_functor_2deriv<T>(arc, radius), guess, min, max, get_digits, it);
+ //<-
+ iters = it;
+ //->
+ return result;
+} // nth_2deriv Halley
+//]
+// Using 1st and 2nd derivatives using Schroder algorithm.
+
+template <class T = double>
+T elliptic_root_2deriv_s(T arc, T radius)
+{ // return nth root of x using 1st and 2nd derivatives and Schroder.
+
+ using namespace std; // Help ADL of std functions.
+ using namespace boost::math::tools; // For schroder_iterate.
+
+ BOOST_STATIC_ASSERT_MSG(boost::is_integral<T>::value == false, "Only floating-point type types can be used!");
+
+ T guess = sqrt(arc * arc / 16 - radius * radius);
+ T min = 0; // Minimum possible value is zero.
+ T max = arc; // radius can't be larger than the arc length.
+
+ int digits = std::numeric_limits<T>::digits; // Maximum possible binary digits accuracy for type T.
+ int get_digits = static_cast<int>(digits * digits_accuracy);
+ const boost::uintmax_t maxit = 20;
+ boost::uintmax_t it = maxit;
+ T result = schroder_iterate(elliptic_root_functor_2deriv<T>(arc, radius), guess, min, max, get_digits, it);
+ iters = it;
+
+ return result;
+} // T elliptic_root_2deriv_s Schroder
+
+//////////////////////////////////////////////////////// end of algorithms - perhaps in a separate .hpp?
+
+//! Print 4 floating-point types info: max_digits10, digits and required accuracy digits as a Quickbook table.
+int table_type_info(double digits_accuracy)
+{
+ std::string qbk_name = full_roots_name; // Prefix by boost_root file.
+
+ qbk_name += "type_info_table";
+ std::stringstream ss;
+ ss.precision(3);
+ ss << "_" << digits_accuracy * 100;
+ qbk_name += ss.str();
+
+#ifdef _MSC_VER
+ qbk_name += "_msvc.qbk";
+#else // assume GCC
+ qbk_name += "_gcc.qbk";
+#endif
+
+ // Example: type_info_table_100_msvc.qbk
+ fout.open(qbk_name, std::ios_base::out);
+
+ if (fout.is_open())
+ {
+ std::cout << "Output type table to " << qbk_name << std::endl;
+ }
+ else
+ { // Failed to open.
+ std::cout << " Open file " << qbk_name << " for output failed!" << std::endl;
+ std::cout << "errno " << errno << std::endl;
+ return errno;
+ }
+
+ fout <<
+ "[/"
+ << qbk_name
+ << "\n"
+ "Copyright 2015 Paul A. Bristow.""\n"
+ "Copyright 2015 John Maddock.""\n"
+ "Distributed under the Boost Software License, Version 1.0.""\n"
+ "(See accompanying file LICENSE_1_0.txt or copy at""\n"
+ "http://www.boost.org/LICENSE_1_0.txt).""\n"
+ "]""\n"
+ << std::endl;
+
+ fout << "[h6 Fraction of maximum possible bits of accuracy required is " << digits_accuracy << ".]\n" << std::endl;
+
+ std::string table_id("type_info");
+ table_id += ss.str(); // Fraction digits accuracy.
+
+#ifdef _MSC_VER
+ table_id += "_msvc";
+#else // assume GCC
+ table_id += "_gcc";
+#endif
+
+ fout << "[table:" << table_id << " Digits for float, double, long double and cpp_bin_float_50\n"
+ << "[[type name] [max_digits10] [binary digits] [required digits]]\n";// header.
+
+ // For all fout types:
+
+ fout << "[[" << "float" << "]"
+ << "[" << std::numeric_limits<float>::max_digits10 << "]" // max_digits10
+ << "[" << std::numeric_limits<float>::digits << "]"// < "Binary digits
+ << "[" << static_cast<int>(std::numeric_limits<float>::digits * digits_accuracy) << "]]\n"; // Accuracy digits.
+
+ fout << "[[" << "float" << "]"
+ << "[" << std::numeric_limits<double>::max_digits10 << "]" // max_digits10
+ << "[" << std::numeric_limits<double>::digits << "]"// < "Binary digits
+ << "[" << static_cast<int>(std::numeric_limits<double>::digits * digits_accuracy) << "]]\n"; // Accuracy digits.
+
+ fout << "[[" << "long double" << "]"
+ << "[" << std::numeric_limits<long double>::max_digits10 << "]" // max_digits10
+ << "[" << std::numeric_limits<long double>::digits << "]"// < "Binary digits
+ << "[" << static_cast<int>(std::numeric_limits<long double>::digits * digits_accuracy) << "]]\n"; // Accuracy digits.
+
+ fout << "[[" << "cpp_bin_float_50" << "]"
+ << "[" << std::numeric_limits<cpp_bin_float_50>::max_digits10 << "]" // max_digits10
+ << "[" << std::numeric_limits<cpp_bin_float_50>::digits << "]"// < "Binary digits
+ << "[" << static_cast<int>(std::numeric_limits<cpp_bin_float_50>::digits * digits_accuracy) << "]]\n"; // Accuracy digits.
+
+ fout << "] [/table table_id_msvc] \n" << std::endl; // End of table.
+
+ fout.close();
+ return 0;
+} // type_table
+
+//! Evaluate root N timing for each algorithm, and for one floating-point type T.
+template <typename T>
+int test_root(cpp_bin_float_100 big_radius, cpp_bin_float_100 big_arc, cpp_bin_float_100 answer, const char* type_name, std::size_t type_no)
+{
+ std::size_t max_digits = 2 + std::numeric_limits<T>::digits * 3010 / 10000;
+ // For new versions use max_digits10
+ // std::cout.precision(std::numeric_limits<T>::max_digits10);
+ std::cout.precision(max_digits);
+ std::cout << std::showpoint << std::endl; // Show trailing zeros too.
+
+ root_infos.push_back(root_info());
+
+ root_infos[type_no].max_digits10 = max_digits;
+ root_infos[type_no].full_typename = typeid(T).name(); // Full typename.
+ root_infos[type_no].short_typename = type_name; // Short typename.
+ root_infos[type_no].bin_digits = std::numeric_limits<T>::digits;
+ root_infos[type_no].get_digits = static_cast<int>(std::numeric_limits<T>::digits * digits_accuracy);
+
+ T radius = static_cast<T>(big_radius);
+ T arc = static_cast<T>(big_arc);
+
+ T result; // root
+ T sum = 0;
+ T ans = static_cast<T>(answer);
+
+ using boost::timer::nanosecond_type;
+ using boost::timer::cpu_times;
+ using boost::timer::cpu_timer;
+
+ long eval_count = boost::is_floating_point<T>::value ? 1000000 : 10000; // To give a sufficiently stable timing for the fast built-in types,
+ // This takes an inconveniently long time for multiprecision cpp_bin_float_50 etc types.
+
+ cpu_times now; // Holds wall, user and system times.
+
+ { // Evaluate times etc for each algorithm.
+ //algorithm_names.push_back("TOMS748"); //
+ cpu_timer ti; // Can start, pause, resume and stop, and read elapsed.
+ ti.start();
+ for(long i = eval_count; i >= 0; --i)
+ {
+ result = elliptic_root_noderiv(radius, arc); //
+ sum += result;
+ }
+ now = ti.elapsed();
+ int time = static_cast<int>(now.user / eval_count);
+ root_infos[type_no].times.push_back(time); // CPU time taken.
+ if (time < root_infos[type_no].min_time)
+ {
+ root_infos[type_no].min_time = time;
+ }
+ ti.stop();
+ long int distance = static_cast<int>(boost::math::float_distance<T>(result, ans));
+ root_infos[type_no].distances.push_back(distance);
+ root_infos[type_no].iterations.push_back(iters); //
+ root_infos[type_no].full_results.push_back(result);
+ }
+ {
+ // algorithm_names.push_back("Newton"); // algorithm
+ cpu_timer ti; // Can start, pause, resume and stop, and read elapsed.
+ ti.start();
+ for(long i = eval_count; i >= 0; --i)
+ {
+ result = elliptic_root_1deriv(radius, arc); //
+ sum += result;
+ }
+ now = ti.elapsed();
+ int time = static_cast<int>(now.user / eval_count);
+ root_infos[type_no].times.push_back(time); // CPU time taken.
+ if (time < root_infos[type_no].min_time)
+ {
+ root_infos[type_no].min_time = time;
+ }
+
+ ti.stop();
+ long int distance = static_cast<int>(boost::math::float_distance<T>(result, ans));
+ root_infos[type_no].distances.push_back(distance);
+ root_infos[type_no].iterations.push_back(iters); //
+ root_infos[type_no].full_results.push_back(result);
+ }
+ {
+ //algorithm_names.push_back("Halley"); // algorithm
+ cpu_timer ti; // Can start, pause, resume and stop, and read elapsed.
+ ti.start();
+ for(long i = eval_count; i >= 0; --i)
+ {
+ result = elliptic_root_2deriv(radius, arc); //
+ sum += result;
+ }
+ now = ti.elapsed();
+ int time = static_cast<int>(now.user / eval_count);
+ root_infos[type_no].times.push_back(time); // CPU time taken.
+ ti.stop();
+ if (time < root_infos[type_no].min_time)
+ {
+ root_infos[type_no].min_time = time;
+ }
+ long int distance = static_cast<int>(boost::math::float_distance<T>(result, ans));
+ root_infos[type_no].distances.push_back(distance);
+ root_infos[type_no].iterations.push_back(iters); //
+ root_infos[type_no].full_results.push_back(result);
+ }
+ {
+ // algorithm_names.push_back("Schr'''&#xf6;'''der"); // algorithm
+ cpu_timer ti; // Can start, pause, resume and stop, and read elapsed.
+ ti.start();
+ for(long i = eval_count; i >= 0; --i)
+ {
+ result = elliptic_root_2deriv_s(arc, radius); //
+ sum += result;
+ }
+ now = ti.elapsed();
+ int time = static_cast<int>(now.user / eval_count);
+ root_infos[type_no].times.push_back(time); // CPU time taken.
+ if (time < root_infos[type_no].min_time)
+ {
+ root_infos[type_no].min_time = time;
+ }
+ ti.stop();
+ long int distance = static_cast<int>(boost::math::float_distance<T>(result, ans));
+ root_infos[type_no].distances.push_back(distance);
+ root_infos[type_no].iterations.push_back(iters); //
+ root_infos[type_no].full_results.push_back(result);
+ }
+ for (size_t i = 0; i != root_infos[type_no].times.size(); i++) // For each time.
+ { // Normalize times.
+ root_infos[type_no].normed_times.push_back(static_cast<double>(root_infos[type_no].times[i]) / root_infos[type_no].min_time);
+ }
+
+ std::cout << "Accumulated result was: " << sum << std::endl;
+
+ return 4; // eval_count of how many algorithms used.
+} // test_root
+
+/*! Fill array of times, interations, etc for Nth root for all 4 types,
+ and write a table of results in Quickbook format.
+ */
+void table_root_info(cpp_bin_float_100 radius, cpp_bin_float_100 arc)
+{
+ using std::abs;
+
+ std::cout << nooftypes << " floating-point types tested:" << std::endl;
+#if defined(_DEBUG) || !defined(NDEBUG)
+ std::cout << "Compiled in debug mode." << std::endl;
+#else
+ std::cout << "Compiled in optimise mode." << std::endl;
+#endif
+ std::cout << "FP hardware " << fp_hardware << std::endl;
+ // Compute the 'right' answer for root N at 100 decimal digits.
+ cpp_bin_float_100 full_answer = elliptic_root_noderiv(radius, arc);
+
+ root_infos.clear(); // Erase any previous data.
+ // Fill the elements of the array for each floating-point type.
+
+ test_root<float>(radius, arc, full_answer, "float", 0);
+ test_root<double>(radius, arc, full_answer, "double", 1);
+ test_root<long double>(radius, arc, full_answer, "long double", 2);
+ test_root<cpp_bin_float_50>(radius, arc, full_answer, "cpp_bin_float_50", 3);
+
+ // Use info from 4 floating point types to
+
+ // Prepare Quickbook table for a single root
+ // with columns of times, iterations, distances repeated for various floating-point types,
+ // and 4 rows for each algorithm.
+
+ std::stringstream table_info;
+ table_info.precision(3);
+ table_info << "[table:elliptic root with radius " << radius << " and arc length " << arc << ") for float, double, long double and cpp_bin_float_50 types";
+ if (fp_hardware != "")
+ {
+ table_info << ", using " << fp_hardware;
+ }
+ table_info << std::endl;
+
+ fout << table_info.str()
+ << "[[][float][][][] [][double][][][] [][long d][][][] [][cpp50][][]]\n"
+ << "[[Algo ]";
+ for (size_t tp = 0; tp != nooftypes; tp++)
+ { // For all types:
+ fout << "[Its]" << "[Times]" << "[Norm]" << "[Dis]" << "[ ]";
+ }
+ fout << "]" << std::endl;
+
+ // Row for all algorithms.
+ for (std::size_t algo = 0; algo != noofalgos; algo++)
+ {
+ fout << "[[" << std::left << std::setw(9) << algo_names[algo] << "]";
+ for (size_t tp = 0; tp != nooftypes; tp++)
+ { // For all types:
+ fout
+ << "[" << std::right << std::showpoint
+ << std::setw(3) << std::setprecision(2) << root_infos[tp].iterations[algo] << "]["
+ << std::setw(5) << std::setprecision(5) << root_infos[tp].times[algo] << "][";
+ fout << std::setw(3) << std::setprecision(3);
+ double normed_time = root_infos[tp].normed_times[algo];
+ if (abs(normed_time - 1.00) <= 0.05)
+ { // At or near the best time, so show as blue.
+ fout << "[role blue " << normed_time << "]";
+ }
+ else if (abs(normed_time) > 4.)
+ { // markedly poor so show as red.
+ fout << "[role red " << normed_time << "]";
+ }
+ else
+ { // Not the best, so normal black.
+ fout << normed_time;
+ }
+ fout << "]["
+ << std::setw(3) << std::setprecision(2) << root_infos[tp].distances[algo] << "][ ]";
+ } // tp
+ fout << "]" << std::endl;
+ } // for algo
+ fout << "] [/end of table root]\n";
+} // void table_root_info
+
+/*! Output program header, table of type info, and tables for 4 algorithms and 4 floating-point types,
+ for Nth root required digits_accuracy.
+ */
+
+int roots_tables(cpp_bin_float_100 radius, cpp_bin_float_100 arc, double digits_accuracy)
+{
+ ::digits_accuracy = digits_accuracy;
+ // Save globally so that it is available to root-finding algorithms. Ugly :-(
+
+#if defined(_DEBUG) || !defined(NDEBUG)
+ std::string debug_or_optimize("Compiled in debug mode.");
+#else
+ std::string debug_or_optimize("Compiled in optimise mode.");
+#endif
+
+ // Create filename for roots_table
+ std::string qbk_name = full_roots_name;
+ qbk_name += "elliptic_table";
+
+ std::stringstream ss;
+ ss.precision(3);
+ // ss << "_" << N // now put all the tables in one .qbk file?
+ ss << "_" << digits_accuracy * 100
+ << std::flush;
+ // Assume only save optimize mode runs, so don't add any _DEBUG info.
+ qbk_name += ss.str();
+
+#ifdef _MSC_VER
+ qbk_name += "_msvc";
+#else // assume GCC
+ qbk_name += "_gcc";
+#endif
+ if (fp_hardware != "")
+ {
+ qbk_name += fp_hardware;
+ }
+ qbk_name += ".qbk";
+
+ fout.open(qbk_name, std::ios_base::out);
+
+ if (fout.is_open())
+ {
+ std::cout << "Output root table to " << qbk_name << std::endl;
+ }
+ else
+ { // Failed to open.
+ std::cout << " Open file " << qbk_name << " for output failed!" << std::endl;
+ std::cout << "errno " << errno << std::endl;
+ return errno;
+ }
+
+ fout <<
+ "[/"
+ << qbk_name
+ << "\n"
+ "Copyright 2015 Paul A. Bristow.""\n"
+ "Copyright 2015 John Maddock.""\n"
+ "Distributed under the Boost Software License, Version 1.0.""\n"
+ "(See accompanying file LICENSE_1_0.txt or copy at""\n"
+ "http://www.boost.org/LICENSE_1_0.txt).""\n"
+ "]""\n"
+ << std::endl;
+
+ // Print out the program/compiler/stdlib/platform names as a Quickbook comment:
+ fout << "\n[h6 Program [@../../example/" << short_file_name(sourcefilename) << " " << short_file_name(sourcefilename) << "],\n "
+ << BOOST_COMPILER << ", "
+ << BOOST_STDLIB << ", "
+ << BOOST_PLATFORM << "\n"
+ << debug_or_optimize
+ << ((fp_hardware != "") ? ", " + fp_hardware : "")
+ << "]" // [h6 close].
+ << std::endl;
+
+ //fout << "Fraction of full accuracy " << digits_accuracy << std::endl;
+
+ table_root_info(radius, arc);
+
+ fout.close();
+
+ // table_type_info(digits_accuracy);
+
+ return 0;
+} // roots_tables
+
+
+int main()
+{
+ using namespace boost::multiprecision;
+ using namespace boost::math;
+
+
+ try
+ {
+ std::cout << "Tests run with " << BOOST_COMPILER << ", "
+ << BOOST_STDLIB << ", " << BOOST_PLATFORM << ", ";
+
+// How to: Configure Visual C++ Projects to Target 64-Bit Platforms
+// https://msdn.microsoft.com/en-us/library/9yb4317s.aspx
+
+#ifdef _M_X64 // Defined for compilations that target x64 processors.
+ std::cout << "X64 " << std::endl;
+ fp_hardware += "_X64";
+#else
+# ifdef _M_IX86
+ std::cout << "X32 " << std::endl;
+ fp_hardware += "_X86";
+# endif
+#endif
+
+#ifdef _M_AMD64
+ std::cout << "AMD64 " << std::endl;
+ // fp_hardware += "_AMD64";
+#endif
+
+// https://msdn.microsoft.com/en-us/library/7t5yh4fd.aspx
+// /arch (x86) options /arch:[IA32|SSE|SSE2|AVX|AVX2]
+// default is to use SSE and SSE2 instructions by default.
+// https://msdn.microsoft.com/en-us/library/jj620901.aspx
+// /arch (x64) options /arch:AVX and /arch:AVX2
+
+// MSVC doesn't bother to set these SSE macros!
+// http://stackoverflow.com/questions/18563978/sse-sse2-is-enabled-control-in-visual-studio
+// https://msdn.microsoft.com/en-us/library/b0084kay.aspx predefined macros.
+
+// But some of these macros are *not* defined by MSVC,
+// unlike AVX (but *are* defined by GCC and Clang).
+// So the macro code above does define them.
+#if (defined(_M_AMD64) || defined (_M_X64))
+# define _M_X64
+# define __SSE2__
+#else
+# ifdef _M_IX86_FP // Expands to an integer literal value indicating which /arch compiler option was used:
+ std::cout << "Floating-point _M_IX86_FP = " << _M_IX86_FP << std::endl;
+# if (_M_IX86_FP == 2) // 2 if /arch:SSE2, /arch:AVX or /arch:AVX2
+# define __SSE2__ // x32
+# elif (_M_IX86_FP == 1) // 1 if /arch:SSE was used.
+# define __SSE__ // x32
+# elif (_M_IX86_FP == 0) // 0 if /arch:IA32 was used.
+# define _X32 // No special FP instructions.
+# endif
+# endif
+#endif
+// Set the fp_hardware that is used in the .qbk filename.
+#ifdef __AVX2__
+ std::cout << "Floating-point AVX2 " << std::endl;
+ fp_hardware += "_AVX2";
+# else
+# ifdef __AVX__
+ std::cout << "Floating-point AVX " << std::endl;
+ fp_hardware += "_AVX";
+# else
+# ifdef __SSE2__
+ std::cout << "Floating-point SSE2 " << std::endl;
+ fp_hardware += "_SSE2";
+# else
+# ifdef __SSE__
+ std::cout << "Floating-point SSE " << std::endl;
+ fp_hardware += "_SSE";
+# endif
+# endif
+# endif
+# endif
+
+#ifdef _M_IX86
+ std::cout << "Floating-point X86 _M_IX86 = " << _M_IX86 << std::endl;
+ // https://msdn.microsoft.com/en-us/library/aa273918%28v=vs.60%29.aspx#_predir_table_1..3
+ // 600 = Pentium Pro
+#endif
+
+#ifdef _MSC_FULL_VER
+ std::cout << "Floating-point _MSC_FULL_VER " << _MSC_FULL_VER << std::endl;
+#endif
+
+#ifdef __MSVC_RUNTIME_CHECKS
+ std::cout << "Runtime __MSVC_RUNTIME_CHECKS " << std::endl;
+#endif
+
+ BOOST_MATH_CONTROL_FP;
+
+ cpp_bin_float_100 radius("28.");
+ cpp_bin_float_100 arc("300.");
+ // Compute full answer to more than precision of tests.
+ //T value = 28.; // integer (exactly representable as floating-point)
+ // whose cube root is *not* exactly representable.
+ // Wolfram Alpha command N[28 ^ (1 / 3), 100] computes cube root to 100 decimal digits.
+ // 3.036588971875662519420809578505669635581453977248111123242141654169177268411884961770250390838097895
+
+ std::cout.precision(100);
+ std::cout << "radius 1" << radius << std::endl;
+ std::cout << "arc length" << arc << std::endl;
+ // std::cout << ",\n""answer = " << full_answer << std::endl;
+ std::cout.precision(6);
+ // cbrt cpp_bin_float_100 full_answer("3.036588971875662519420809578505669635581453977248111123242141654169177268411884961770250390838097895");
+
+ // Output the table of types, maxdigits10 and digits and required digits for some accuracies.
+
+ // Output tables for some roots at full accuracy.
+ roots_tables(radius, arc, 1.);
+
+ // Output tables for some roots at less accuracy.
+ //roots_tables(full_value, 0.75);
+
+ return boost::exit_success;
+ }
+ catch (std::exception const& ex)
+ {
+ std::cout << "exception thrown: " << ex.what() << std::endl;
+ return boost::exit_failure;
+ }
+} // int main()
+
+/*
+
+*/