ceph/src/boost/libs/units/example/autoprefixes.cpp

   1 // Boost.Units - A C++ library for zero-overhead dimensional analysis and
   2 // unit/quantity manipulation and conversion
   3 //
   4 // Copyright (C) 2003-2008 Matthias Christian Schabel
   5 // Copyright (C) 2008 Steven Watanabe
   6 //
   7 // Distributed under the Boost Software License, Version 1.0. (See
   8 // accompanying file LICENSE_1_0.txt or copy at
   9 // http://www.boost.org/LICENSE_1_0.txt)
  10
  11 /**
  12 \file
  13
  14 \brief Example of using autoprefixes.
  15
  16 \details
  17 Example of using engineering (10^3) and binary (2^10) autoprefixes.
  18
  19 Output:
  20 @verbatim
  21 autoprefixes.cpp
  22 using native typeof
  23 Linking...
  24 Embedding manifest...
  25 Autorun "j:\Cpp\Misc\debug\autoprefixes.exe"
  26 2.345 m
  27 2.345 km
  28 5.49902 MJ
  29 5.49902 megajoule
  30 2.048 kb
  31 2 Kib
  32 2345.6
  33 23456
  34 2345.6
  35 23456
  36 m
  37 meter
  38 0
  39 1
  40 @endverbatim
  41 //[autoprefixes_output
  42
  43 //] [/autoprefixes_output
  44
  45 **/
  46
  47 #include <iostream>
  48
  49 #include <boost/units/io.hpp>
  50 #include <boost/units/pow.hpp>
  51 #include <boost/units/systems/si.hpp>
  52 #include <boost/units/systems/si/io.hpp>
  53 #include <boost/units/quantity.hpp>
  54
  55 struct byte_base_unit : boost::units::base_unit<byte_base_unit, boost::units::dimensionless_type, 3>
  56 {
  57   static const char* name() { return("byte"); }
  58   static const char* symbol() { return("b"); }
  59 };
  60
  61 struct thing_base_unit : boost::units::base_unit<thing_base_unit, boost::units::dimensionless_type, 4>
  62 {
  63   static const char* name() { return("thing"); }
  64   static const char* symbol() { return(""); }
  65 };
  66
  67 struct euro_base_unit : boost::units::base_unit<euro_base_unit, boost::units::dimensionless_type, 5>
  68 {
  69   static const char* name() { return("EUR"); }
  70   static const char* symbol() { return("\80"); }
  71 };
  72
  73 int main()
  74 {
  75   using std::cout;
  76   using std::endl;
  77
  78   using namespace boost::units;
  79   using namespace boost::units::si;
  80
  81  //[autoprefixes_snippet_1
  82   using boost::units::binary_prefix;
  83   using boost::units::engineering_prefix;
  84   using boost::units::no_prefix;
  85
  86   quantity<length> l = 2.345 * meters;   // A quantity of length, in units of meters.
  87   cout << engineering_prefix << l << endl; // Outputs "2.345 m".
  88   l =  1000.0 * l; // Increase it by 1000, so expect a k prefix.
  89   // Note that a double 1000.0 is required - an integer will fail to compile.
  90   cout << engineering_prefix << l << endl; // Output autoprefixed with k to "2.345 km".
  91
  92   quantity<energy> e = kilograms * pow<2>(l / seconds); // A quantity of energy.
  93   cout << engineering_prefix << e << endl; // 5.49902 MJ
  94   cout << name_format << engineering_prefix << e << endl; // 5.49902 megaJoule
  95   //] [/autoprefixes_snippet_1]
  96
  97   //[autoprefixes_snippet_2
  98   // Don't forget that the units name or symbol format specification is persistent.
  99   cout << symbol_format << endl; // Resets the format to the default symbol format.
 100
 101   quantity<byte_base_unit::unit_type> b = 2048. * byte_base_unit::unit_type();
 102   cout << engineering_prefix << b << endl;  // 2.048 kb
 103   cout << symbol_format << binary_prefix << b << endl; //  "2 Kib"
 104   //] [/autoprefixes_snippet_2]
 105
 106   // Note that scalar dimensionless values are *not* prefixed automatically by the engineering_prefix or binary_prefix iostream manipulators.
 107   //[autoprefixes_snippet_3
 108   const double s1 = 2345.6;
 109   const long x1 = 23456;
 110   cout << engineering_prefix << s1 << endl; // 2345.6
 111   cout << engineering_prefix << x1 << endl; // 23456
 112
 113   cout << binary_prefix << s1 << endl; // 2345.6
 114   cout << binary_prefix << x1 << endl; // 23456
 115   //] [/autoprefixes_snippet_3]
 116
 117   //[autoprefixes_snippet_4
 118   const length L; // A unit of length (but not a quantity of length).
 119   cout << L << endl; // Default length unit is meter,
 120   // but default is symbol format so output is just "m".
 121   cout << name_format << L << endl; // default length name is "meter".
 122   //] [/autoprefixes_snippet_4]
 123
 124   //[autoprefixes_snippet_5
 125   no_prefix(cout); // Clear any prefix flag.
 126   cout << no_prefix << endl; // Clear any prefix flag using `no_prefix` manipulator.
 127   //] [/autoprefixes_snippet_5]
 128
 129   //[autoprefixes_snippet_6
 130   cout << boost::units::get_autoprefix(cout) << endl; // 8 is `autoprefix_binary` from `enum autoprefix_mode`.
 131   cout << boost::units::get_format(cout) << endl; // 1 is `name_fmt` from `enum format_mode`.
 132   //] [/autoprefixes_snippet_6]
 133
 134
 135   quantity<thing_base_unit::unit_type> t = 2048. * thing_base_unit::unit_type();
 136   cout << name_format << engineering_prefix << t << endl;  // 2.048 kilothing
 137   cout << symbol_format << engineering_prefix << t << endl;  // 2.048 k
 138
 139   cout  << binary_prefix << t << endl; //  "2 Ki"
 140
 141   quantity<euro_base_unit::unit_type> ce = 2048. * euro_base_unit::unit_type();
 142   cout << name_format << engineering_prefix << ce << endl;  // 2.048 kiloEUR
 143   cout << symbol_format << engineering_prefix << ce << endl;  // 2.048 k\80
 144
 145
 146     return 0;
 147 } // int main()
 148