[Boost-commit] svn:boost r75288 - sandbox/multiprecision/libs/multiprecision/example/using_library_example

Subject: [Boost-commit] svn:boost r75288 - sandbox/multiprecision/libs/multiprecision/example/using_library_example
From: pbristow_at_[hidden]
Date: 2011-11-03 13:42:33

Author: pbristow
Date: 2011-11-03 13:42:32 EDT (Thu, 03 Nov 2011)
New Revision: 75288
URL: http://svn.boost.org/trac/boost/changeset/75288

Log:
examples using pre-built library
Added:
   sandbox/multiprecision/libs/multiprecision/example/using_library_example/
   sandbox/multiprecision/libs/multiprecision/example/using_library_example/using_library_example.cpp   (contents, props changed)

Added: sandbox/multiprecision/libs/multiprecision/example/using_library_example/using_library_example.cpp
==============================================================================
--- (empty file)
+++ sandbox/multiprecision/libs/multiprecision/example/using_library_example/using_library_example.cpp	2011-11-03 13:42:32 EDT (Thu, 03 Nov 2011)
@@ -0,0 +1,162 @@
+//! \file
+
+// Copyright Paul A. Bristow 2011.
+
+// 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)
+
+// This file is written to be included from a Quickbook .qbk document.
+// It can be compiled by the C++ compiler, and run. Any output can
+// also be added here as comment or included or pasted in elsewhere.
+// Caution: this file contains Quickbook markup as well as code
+// and comments: don't change any of the special comment markups!
+
+// This file also includes Doxygen-style documentation about the function of the code.
+// See http://www.doxygen.org for details.
+
+// Below are snippets of code that can be included into a Quickbook program.
+
+//[using_library_example_1
+
+/*` 
+
+[h5 Multiprecision example using a pre-built library.]
+
+Select the mp_float back-end big-number type
+by defining BOOST_MULTIPRECISION_BACKEND_MP_FLOAT_TYPE_xxx, for example,
+as a compiler defined preprocessor macro.
+
+For example [^#define BOOST_MULTIPRECISION_BACKEND_MP_FLOAT_TYPE_EFX;]
+in MS Project Properties, Preprocessor, Preprocessor definitions
+or select backend type EFX (which has the Boost licence) below
+with the #define below.
+*/
+
+#define BOOST_MULTIPRECISION_BACKEND_MP_FLOAT_TYPE_EFX
+
+/*`
+[note If you have other files that use mp_float, they will all need this #define,
+so a single project-wide definition may be more convenient.]
+
+[warning Ensure that MS language extensions are NOT disabled.]
+
+Includes are needed to use multiprecision, mp_float.hpp for arithmetic and trig functions,
+and mp_float_functions.hpp to be able to use various constants.
+*/
+
+#include <boost/multiprecision/mp_float.hpp> 
+#include <boost/multiprecision/mp_float_functions.hpp> // for constants.
+
+//] [using_library_example_1] // This ends the snippet.
+
+#include <iostream>
+using std::cout;
+using std::cin;
+using std::endl;
+using std::dec;
+using std::hex;
+using std::boolalpha;
+using std::showpoint;
+
+#include <iomanip>
+using std::setprecision;
+using std::setw;
+#include <string>
+using std::string;
+
+#include <cassert>
+#include <limits>
+
+// using namespace boost::multiprecision; // Not recommended.
+
+//[using_library_example_2
+int main()
+{
+  using boost::multiprecision::mp_float;
+
+  cout << "BOOST_MULTIPRECISION_BACKEND_MP_FLOAT_DIGITS10 = " << BOOST_MULTIPRECISION_BACKEND_MP_FLOAT_DIGITS10 << endl;
+
+  cout.precision(std::numeric_limits<mp_float>::max_digits10);
+  cout << "std::numeric_limits<multiprecision>::max_digits10  = " << std::numeric_limits<mp_float>::max_digits10 << endl;
+  cout << "std::numeric_limits<multiprecision>::digits10  = " << std::numeric_limits<mp_float>::digits10 << endl;
+
+
+//] [using_library_example_2]
+
+//[using_library_example_3
+  mp_float float_ten(10);
+
+  mp_float float_hundred = boost::multiprecision::hundred();
+
+  mp_float googol;
+  googol = pow(float_ten, float_hundred);
+  cout << "googol = " << showpoint << googol << endl; //  = 1.000000000000000000000000000000000000000000000000000000000e+100
+
+  mp_float googolplex;
+  googolplex = pow(float_ten, googol);
+  cout << "googolplex = " << showpoint << googolplex << endl; // inf!
+
+  mp_float mp_float_max = boost::multiprecision::value_max();
+  cout << "std::numeric_limits<mp_float>::max() = " << std::numeric_limits<mp_float>::max() << endl;
+
+
+  //cout << "boost::multiprecision::value_max() = " << showpoint << mp_float_max << endl;
+  //] [using_library_example_3]
+
+//[using_library_example_4
+
+  using boost::multiprecision::pi; // Convenient to permit just pi().
+
+  mp_float my_pi;
+  my_pi = pi();
+  cout << "boost::multiprecision::pi(); = " << pi() << endl;
+  cout << " 4/3 pi(); = " << 4 * pi()/3 << endl;
+
+//] [using_library_example_4]
+
+//[using_library_example_5
+
+  //mp_float r = 41/47; // zero!
+  // mp_float r = (41.)/47; //
+  //mp_float r = 41./47; // 1.190969240806423525258295702651707417479877984460367184892
+  mp_float r = static_cast<mp_float>(41)/47; //
+
+  mp_float t = tan (r);
+
+  cout << "tan (41/47) = " << t << endl;
+
+  //1.190969240806423525258295702651707417479877984460367184892
+
+  //1.190969240806423433854995358643916551662102246296735478573
+  //1.1909692408064234338549953586439165516621022462967354785730460059437472
+
+//] [using_library_example_5]
+
+} // int main()
+
+/*
+
+//[library_eg_output
+
+ using_library_example.cpp
+  Generating code
+  Finished generating code
+  using_library_example.vcxproj -> I:\boost-sandbox\multiprecision\libs\multiprecision\build\Release\using_library_example.exe
+  BOOST_MULTIPRECISION_BACKEND_MP_FLOAT_DIGITS10 = 50
+  std::numeric_limits<multiprecision>::max_digits10  = 58
+  std::numeric_limits<multiprecision>::digits10  = 50
+  googol = 1.000000000000000000000000000000000000000000000000000000000e+100
+  googolplex = inf
+  std::numeric_limits<mp_float>::max() = 1.000000000000000000000000000000000000000000000000000000000e+003063937869882635617
+  boost::multiprecision::pi(); = 3.141592653589793238462643383279502884197169399375105820975
+   4/3 pi(); = 4.188790204786390984616857844372670512262892532500141094633
+  tan (41/47) = 1.190969240806423433854995358643916551662102246296735478573
+
+//] [/library_eg_output]
+
+
+
+*/
+