Merge branch 'master' into chiphogg/switch-to-mag

example/CMakeLists.txt

@@ -37,6 +37,7 @@ add_example(conversion_factor mp-units::core-fmt mp-units::core-io mp-units::si)
 add_example(custom_systems mp-units::core-io mp-units::si)
 add_example(hello_units mp-units::core-fmt mp-units::core-io mp-units::si mp-units::si-international)
 add_example(measurement mp-units::core-io mp-units::si)
+add_example(si_constants mp-units::core-fmt mp-units::si)
 
 if(NOT ${projectPrefix}LIBCXX)
     add_subdirectory(glide_computer)

example/kalman_filter/kalman.h

@@ -38,20 +38,20 @@ concept QuantityOrQuantityPoint =
   units::Quantity<T> || units::QuantityPoint<T>;  // TODO Should it also account for `kinds`?
 
 template<typename... Qs>
-inline constexpr bool are_derivatives = false;
+inline constexpr bool are_time_derivatives = false;
 
 template<typename Q>
-inline constexpr bool are_derivatives<Q> = true;
+inline constexpr bool are_time_derivatives<Q> = true;
 
 template<typename Q1, typename Q2, typename... Qs>
-inline constexpr bool are_derivatives<Q1, Q2, Qs...> =
+inline constexpr bool are_time_derivatives<Q1, Q2, Qs...> =
   units::DimensionOfT<typename decltype(Q1::reference / Q2::reference)::dimension,
                       units::isq::dim_time> &&  // TODO Think on how to simplify this
-  are_derivatives<Q2, Qs...>;
+  are_time_derivatives<Q2, Qs...>;
 
 // state
 template<QuantityOrQuantityPoint... QQPs>
-  requires(sizeof...(QQPs) > 0) && (sizeof...(QQPs) <= 3) && are_derivatives<QQPs...>
+  requires(sizeof...(QQPs) > 0) && (sizeof...(QQPs) <= 3) && are_time_derivatives<QQPs...>
 struct state {
   std::tuple<QQPs...> variables_;
   constexpr state(QQPs... qqps) : variables_(std::move(qqps)...) {}

example/si_constants.cpp

@@ -0,0 +1,40 @@
+// 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/isq/si/constants.h>
+#include <iostream>
+
+int main()
+{
+  using namespace units::isq::si::si2019;
+
+  std::cout << "The seven defining constants of the SI and the seven corresponding units they define:\n";
+  std::cout << STD_FMT::format("- hyperfine transition frequency of Cs: {:%.0Q %q}\n",
+                               hyperfine_structure_transition_frequency<>);
+  std::cout << STD_FMT::format("- speed of light in vacuum:             {:%.0Q %q}\n", speed_of_light<>);
+  std::cout << STD_FMT::format("- Planck constant:                      {}\n", planck_constant<>);
+  std::cout << STD_FMT::format("- elementary charge:                    {}\n", elementary_charge<>);
+  std::cout << STD_FMT::format("- Boltzmann constant:                   {}\n", boltzmann_constant<>);
+  std::cout << STD_FMT::format("- Avogadro constant:                    {}\n", avogadro_constant<>);
+  std::cout << STD_FMT::format("- luminous efficacy:                    {}\n", luminous_efficacy<>);
+}