Files
mp-units/example/box_example.cpp
2021-04-02 18:56:28 +02:00

107 lines
4.1 KiB
C++

// The MIT License (MIT)
//
// Copyright (c) 2018 Mateusz Pusz
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
#include <units/format.h>
#include <units/generic/dimensionless.h>
#include <units/isq/si/amount_of_substance.h>
#include <units/isq/si/area.h>
#include <units/isq/si/constants.h>
#include <units/isq/si/density.h>
#include <units/isq/si/force.h>
#include <units/isq/si/length.h>
#include <units/isq/si/mass.h>
#include <units/isq/si/speed.h> // IWYU pragma: keep
#include <units/isq/si/time.h>
#include <units/isq/si/volume.h>
#include <cassert>
#include <iostream>
#include <utility>
namespace {
using namespace units::isq;
using namespace si::references;
inline constexpr Acceleration auto g = si::si2019::standard_gravity<>;
inline constexpr Density auto air_density = 1.225 * (kg / m3);
class Box {
si::area<si::square_metre> base_;
si::length<si::metre> height_;
si::density<si::kilogram_per_metre_cub> density_ = air_density;
public:
constexpr Box(const si::length<si::metre>& length, const si::length<si::metre>& width, si::length<si::metre> height) : base_(length * width), height_(std::move(height)) {}
[[nodiscard]] constexpr si::force<si::newton> filled_weight() const
{
const Volume auto volume = base_ * height_;
const Mass auto mass = density_ * volume;
return mass * g;
}
[[nodiscard]] constexpr si::length<si::metre> fill_level(const si::mass<si::kilogram>& measured_mass) const
{
return height_ * measured_mass * g / filled_weight();
}
[[nodiscard]] constexpr si::volume<si::cubic_metre> spare_capacity(const si::mass<si::kilogram>& measured_mass) const
{
return (height_ - fill_level(measured_mass)) * base_;
}
constexpr void set_contents_density(const si::density<si::kilogram_per_metre_cub>& density_in)
{
assert(density_in > air_density);
density_ = density_in;
}
};
} // namespace
int main()
{
using namespace units;
const si::length<si::metre> height = 200.0 * mm;
auto box = Box(1000.0 * mm, 500.0 * mm, height);
box.set_contents_density(1000.0 * (kg / m3));
const auto fill_time = 200.0 * s; // time since starting fill
const auto measured_mass = 20.0 * kg; // measured mass at fill_time
const Length auto fill_level = box.fill_level(measured_mass);
const Dimensionless auto fill_percent = quantity_cast<percent>(fill_level / height);
const Volume auto spare_capacity = box.spare_capacity(measured_mass);
const auto input_flow_rate = measured_mass / fill_time; // unknown dimension
const Speed auto float_rise_rate = fill_level / fill_time;
const Time auto fill_time_left = (height / fill_level - 1) * fill_time;
std::cout << "mp-units box example...\n";
std::cout << fmt::format("fill height at {} = {} ({} full)\n", fill_time, fill_level, fill_percent);
std::cout << fmt::format("spare_capacity at {} = {}\n", fill_time, spare_capacity);
std::cout << fmt::format("input flow rate after {} = {}\n", fill_time, input_flow_rate);
std::cout << fmt::format("float rise rate = {}\n", float_rise_rate);
std::cout << fmt::format("box full E.T.A. at current flow rate = {}\n", fill_time_left);
}