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- // Boost.Units - A C++ library for zero-overhead dimensional analysis and
- // unit/quantity manipulation and conversion
- //
- // Copyright (C) 2003-2008 Matthias Christian Schabel
- // Copyright (C) 2008 Steven Watanabe
- //
- // 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)
- /**
- \file tutorial.cpp
-
- \brief Basic tutorial using SI units.
- \details
- Tutorial
- Defines a function that computes the work, in joules,
- done by exerting a force in newtons over a specified distance
- in meters and outputs the result to std::cout.
- Also code for computing the complex impedance
- using std::complex<double> as the value type.
- Output:
- @verbatim
- //[tutorial_output
- F = 2 N
- dx = 2 m
- E = 4 J
- V = (12.5,0) V
- I = (3,4) A
- Z = (1.5,-2) Ohm
- I*Z = (12.5,0) V
- I*Z == V? true
- //]
- @endverbatim
- */
- //[tutorial_code
- #include <complex>
- #include <iostream>
- #include <boost/typeof/std/complex.hpp>
- #include <boost/units/systems/si/energy.hpp>
- #include <boost/units/systems/si/force.hpp>
- #include <boost/units/systems/si/length.hpp>
- #include <boost/units/systems/si/electric_potential.hpp>
- #include <boost/units/systems/si/current.hpp>
- #include <boost/units/systems/si/resistance.hpp>
- #include <boost/units/systems/si/io.hpp>
- using namespace boost::units;
- using namespace boost::units::si;
- constexpr
- quantity<energy>
- work(const quantity<force>& F, const quantity<length>& dx)
- {
- return F * dx; // Defines the relation: work = force * distance.
- }
- int main()
- {
- /// Test calculation of work.
- quantity<force> F(2.0 * newton); // Define a quantity of force.
- quantity<length> dx(2.0 * meter); // and a distance,
- quantity<energy> E(work(F,dx)); // and calculate the work done.
-
- std::cout << "F = " << F << std::endl
- << "dx = " << dx << std::endl
- << "E = " << E << std::endl
- << std::endl;
- /// Test and check complex quantities.
- typedef std::complex<double> complex_type; // double real and imaginary parts.
-
- // Define some complex electrical quantities.
- quantity<electric_potential, complex_type> v = complex_type(12.5, 0.0) * volts;
- quantity<current, complex_type> i = complex_type(3.0, 4.0) * amperes;
- quantity<resistance, complex_type> z = complex_type(1.5, -2.0) * ohms;
-
- std::cout << "V = " << v << std::endl
- << "I = " << i << std::endl
- << "Z = " << z << std::endl
- // Calculate from Ohm's law voltage = current * resistance.
- << "I * Z = " << i * z << std::endl
- // Check defined V is equal to calculated.
- << "I * Z == V? " << std::boolalpha << (i * z == v) << std::endl
- << std::endl;
- return 0;
- }
- //]
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