refactor: physical replaced with isq

Refers to #249

docs/CMakeLists.txt

@@ -124,104 +124,104 @@ set(unitsSphinxDocs
     "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/generic/dimensionless.rst"
     "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/generic/unknown.rst"
 
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq.rst"
 
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/natural.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/natural/constants.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/natural/dimensions.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/natural/units.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/natural.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/natural/constants.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/natural/dimensions.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/natural/units.rst"
 
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si_cgs.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/cgs/length.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/cgs/acceleration.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/cgs/area.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/cgs/energy.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/cgs/force.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/cgs/length.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/cgs/mass.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/cgs/power.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/cgs/pressure.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/cgs/speed.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/cgs/time.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si_cgs.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/cgs/length.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/cgs/acceleration.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/cgs/area.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/cgs/energy.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/cgs/force.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/cgs/length.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/cgs/mass.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/cgs/power.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/cgs/pressure.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/cgs/speed.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/cgs/time.rst"
 
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/dimensions_and_concepts.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/dimensions_and_concepts.rst"
 
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si_fps.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/length.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/acceleration.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/area.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/density.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/energy.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/force.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/length.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/mass.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/power.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/pressure.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/speed.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/time.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/fps/volume.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si_fps.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/length.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/acceleration.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/area.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/density.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/energy.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/force.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/length.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/mass.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/power.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/pressure.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/speed.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/time.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/fps/volume.rst"
 
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si_iau.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/iau/length.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si_iau.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/iau/length.rst"
 
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si_imperial.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/imperial/length.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si_imperial.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/imperial/length.rst"
 
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si_international.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/international/area.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/international/length.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/international/speed.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/international/volume.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si_international.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/international/area.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/international/length.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/international/speed.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/international/volume.rst"
 
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/absorbed_dose.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/acceleration.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/amount_of_substance.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/area.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/capacitance.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/catalytic_activity.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/charge_density.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/concentration.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/conductance.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/constants.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/current_density.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/density.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/dynamic_viscosity.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/electric_charge.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/electric_current.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/electric_field_strength.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/energy.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/force.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/frequency.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/heat_capacity.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/inductance.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/length.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/luminance.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/luminous_intensity.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/magnetic_flux.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/magnetic_induction.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/mass.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/molar_energy.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/momentum.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/permeability.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/permittivity.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/power.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/prefixes.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/pressure.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/resistance.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/speed.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/surface_tension.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/thermal_conductivity.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/thermodynamic_temperature.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/time.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/voltage.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/volume.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/absorbed_dose.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/acceleration.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/amount_of_substance.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/area.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/capacitance.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/catalytic_activity.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/charge_density.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/concentration.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/conductance.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/constants.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/current_density.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/density.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/dynamic_viscosity.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/electric_charge.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/electric_current.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/electric_field_strength.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/energy.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/force.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/frequency.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/heat_capacity.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/inductance.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/length.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/luminance.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/luminous_intensity.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/magnetic_flux.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/magnetic_induction.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/mass.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/molar_energy.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/momentum.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/permeability.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/permittivity.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/power.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/prefixes.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/pressure.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/resistance.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/speed.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/surface_tension.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/thermal_conductivity.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/thermodynamic_temperature.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/time.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/voltage.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/volume.rst"
 
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si_typographic.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/typographic/length.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si_typographic.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/typographic/length.rst"
 
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si_us.rst"
-    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/physical/si/us/length.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si_us.rst"
+    "${CMAKE_CURRENT_SOURCE_DIR}/reference/systems/isq/si/us/length.rst"
 
     "${CMAKE_CURRENT_SOURCE_DIR}/references.rst"
 

docs/design.rst

@@ -6,7 +6,7 @@ Design Deep Dive
     For brevity all the code examples in this chapter assume::
 
         using namespace units;
-        using namespace units::physical;
+        using namespace units::isq;
 
 .. toctree::
     :maxdepth: 2

docs/design/directories.rst

@@ -63,4 +63,4 @@ Library Directories Structure
 
     While working with predefined systems please always include a header file with all
     the definitions for the current system to limit the possibility of an ODR violation
-    (e.g. *units/physical/si/si.h*).
+    (e.g. *units/isq/si/si.h*).

docs/design/downcasting.rst

@@ -23,9 +23,9 @@ The above solution does provide a good developer's experience but a really poor
 user. If we will get a compilation error message containing ``dim_capacitance`` in most cases
 the compiler will print the following type instead of the alias::
 
-    units::detail::derived_dimension_base<units::exponent<units::physical::si::dim_electric_current, 2, 1>,
-    units::exponent<units::physical::si::dim_length, -2, 1>, units::exponent<units::physical::si::dim_mass,
-    -1, 1>, units::exponent<units::physical::si::dim_time, 4, 1> >
+    units::detail::derived_dimension_base<units::exponent<units::isq::si::dim_electric_current, 2, 1>,
+    units::exponent<units::isq::si::dim_length, -2, 1>, units::exponent<units::isq::si::dim_mass,
+    -1, 1>, units::exponent<units::isq::si::dim_time, 4, 1> >
 
 You can notice that in case of **mp-units** even this long syntax was carefully selected to
 provide quite good user experience (some other units libraries produce a type that cannot easily

docs/faq.rst

@@ -30,10 +30,10 @@ different dimensions (i.e. height, width, and depth) all of them will just be
 measured in meters.
 
 
-Why other systems are defined in the `physical::si` namespace?
+Why other systems are defined in the `isq::si` namespace?
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-All systems defined in the `physical::si` namespace are defined in terms of
+All systems defined in the `isq::si` namespace are defined in terms of
 base units that are convertible to the :term:`SI` units. This enables conversions
 of units of the same physical dimension between different systems.
 
@@ -125,7 +125,7 @@ error: reference to ‘time’ is ambiguous
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Unfortunately, if `using-directives <https://en.cppreference.com/w/cpp/language/namespace#Using-directives>`_
-(i.e. ``using namespace units::physical::si``) are being used, `units::physical::si::time`
+(i.e. ``using namespace units::isq::si``) are being used, `units::isq::si::time`
 will collide with C `time <https://en.cppreference.com/w/c/chrono/time>`_ function. In
 such a case the library's ``time`` function needs to be prefixed with at least one (or all)
 namespace names.

docs/framework.rst

@@ -6,7 +6,7 @@ Framework Basics
     For brevity all the code examples in this chapter assume::
 
         using namespace units;
-        using namespace units::physical;
+        using namespace units::isq;
 
 .. toctree::
     :maxdepth: 2

docs/framework/dimensions.rst

@@ -171,7 +171,7 @@ provided. For example the SI base dimension of length can be defined as::
     }
 
 In the above code sample ``"L"`` is an base dimension's unique identifier
-and `physical::si::metre` is a :term:`base unit` of this base dimension. We can
+and `isq::si::metre` is a :term:`base unit` of this base dimension. We can
 obtain those back easily with::
 
     static_assert(si::dim_length::symbol == "L");
@@ -206,8 +206,8 @@ The above dimensions can be defined in the library with the
 
     }
 
-In the above code sample `physical::si::square_metre` and
-`physical::si::metre_per_second` are the
+In the above code sample `isq::si::square_metre` and
+`isq::si::metre_per_second` are the
 :term:`coherent derived units <coherent derived unit>` of those derived dimensions.
 
 Coherent unit argument is followed by the list of exponents that form this

docs/framework/quantities.rst

@@ -69,7 +69,7 @@ values the library provides :abbr:`UDL (User Defined Literal)` s for each
 
 Thanks to them the same code can be as simple as::
 
-    using namespace units::physical::si::literals;
+    using namespace units::isq::si::literals;
     auto d = 123._q_km;     // si::length<si::kilometre, long double>
     auto v = 70_q_km_per_h; // si::speed<si::kilometre_per_hour, std::int64_t>
 
@@ -98,7 +98,7 @@ They are defined using a special `one_rep` representation type::
 
 With the above our code can look as follows::
 
-    using namespace units::physical::si::unit_constants;
+    using namespace units::isq::si::unit_constants;
     auto d = 123. * km;     // si::length<si::kilometre, double>
     auto v = 70 * km / h;   // si::speed<si::kilometre_per_hour, int>
 
@@ -121,13 +121,13 @@ UDLs are helpful but they also have some disadvantages compared to Unit Constant
 
    - UDLs::
 
-       using namespace units::physical::si::literals;
+       using namespace units::isq::si::literals;
        auto v1 = 120_q_km / 2_q_h;
        auto v2 = length<kilometre>(distance) / time<hour>(duration);
 
    - Unit Constants::
 
-       using namespace units::physical::si::unit_constants;
+       using namespace units::isq::si::unit_constants;
        auto v1 = 120 * km / (2 * h);
        auto v2 = distance * km / (duration * h);
 
@@ -139,14 +139,14 @@ UDLs are helpful but they also have some disadvantages compared to Unit Constant
 
    - UDLs::
 
-       using namespace units::physical::si::literals;
-       using namespace units::physical::si::cgs::literals;
+       using namespace units::isq::si::literals;
+       using namespace units::isq::si::cgs::literals;
        auto d = 1_q_cm;   // FAILS TO COMPILE
 
    - Unit Constants::
 
-       inline constexpr auto si_cm = units::physical::si::unit_constants::cm;
-       inline constexpr auto cgs_cm = units::physical::si::cgs::unit_constants::cm;
+       inline constexpr auto si_cm = units::isq::si::unit_constants::cm;
+       inline constexpr auto cgs_cm = units::isq::si::cgs::unit_constants::cm;
 
        auto d1 = 1. * si_cm;   // si::length<si::centimetre>
        auto d2 = 1. * cgs_cm;  // si::cgs::length<si::centimetre>
@@ -156,7 +156,7 @@ UDLs are helpful but they also have some disadvantages compared to Unit Constant
 
    - UDLs::
 
-       using namespace units::physical::si::literals;
+       using namespace units::isq::si::literals;
        auto d1 = 123._q_km;   // si::length<si::kilometre, long double>
        auto d2 = 123_q_km;    // si::length<si::kilometre, std::int64_t>
 
@@ -164,7 +164,7 @@ UDLs are helpful but they also have some disadvantages compared to Unit Constant
 
    - Unit Constants::
 
-       using namespace units::physical::si::unit_constants;
+       using namespace units::isq::si::unit_constants;
        auto d1 = 123. * km;   // si::length<si::kilometre, double>
        auto d2 = 123 * km;    // si::length<si::kilometre, int>
        auto d3 = 123.f * km;  // si::length<si::kilometre, float>
@@ -194,7 +194,7 @@ UDLs are helpful but they also have some disadvantages compared to Unit Constant
 The only issue we are aware of with Unit Constants is a potential problem of specifying
 a quantity in denominator::
 
-    using namespace units::physical::si::unit_constants;
+    using namespace units::isq::si::unit_constants;
     Speed auto v = 220 * km / 2 * h;  // FAILS TO COMPILE (not a quantity of a speed dimension)
 
 The above code can be fixed in one of the below ways:
@@ -220,7 +220,7 @@ In case the user does not care about the specific unit and representation but
 requires quantity of a concrete dimension than dimension-specific concepts can
 be used::
 
-    using namespace units::physical::si::literals;
+    using namespace units::isq::si::literals;
     constexpr Length auto d = 123_q_km;  // si::length<si::kilometre, std::int64_t>
 
 .. note::
@@ -235,8 +235,8 @@ assume that the user wants to implement an ``avg_speed`` function that will
 be calculating the average speed based on provided distance and duration
 quantities. The usage of such a function can look as follows::
 
-    using namespace units::physical::si::literals;
-    using namespace units::physical::si::international::literals;
+    using namespace units::isq::si::literals;
+    using namespace units::isq::si::international::literals;
     constexpr Speed auto v1 = avg_speed(220_q_km, 2_q_h);
     constexpr Speed auto v2 = avg_speed(140_q_mi, 2_q_h);
 

docs/framework/text_output.rst

@@ -21,8 +21,8 @@ Output Streams
 The easiest way to print a quantity is to provide its object to the output
 stream::
 
-    using namespace units::physical::si::literals;
-    using namespace units::physical::si::international::literals;
+    using namespace units::isq::si::literals;
+    using namespace units::isq::si::international::literals;
     constexpr Speed auto v1 = avg_speed(220._q_km, 2_q_h);
     constexpr Speed auto v2 = avg_speed(140._q_mi, 2_q_h);
     std::cout << v1 << '\n';  // 110 km/h

docs/framework/units.rst

@@ -388,7 +388,7 @@ and user should not instantiate it by him/her-self. However the user can sometim
 observe this type in case an unit/dimension conversion expression will end up with an
 unknown/undefined unit type like in the below example::
 
-    using namespace units::physical::si::literals;
+    using namespace units::isq::si::literals;
 
     Length auto l = 100_q_km_per_h * 10_q_s;
 

docs/quick_start.rst

@@ -3,11 +3,11 @@ Quick Start
 
 Here is a small example of possible operations::
 
-    #include <units/physical/si/area.h>
-    #include <units/physical/si/frequency.h>
-    #include <units/physical/si/speed.h>
+    #include <units/isq/si/area.h>
+    #include <units/isq/si/frequency.h>
+    #include <units/isq/si/speed.h>
 
-    using namespace units::physical::si;
+    using namespace units::isq::si;
 
     // simple numeric operations
     static_assert(10_q_km / 2 == 5_q_km);
@@ -38,12 +38,12 @@ performed without sacrificing on accuracy. Please see the below example for a qu
 of basic library features::
 
     #include <units/format.h>
-    #include <units/physical/si/speed.h>
-    #include <units/physical/si/international/speed.h>
+    #include <units/isq/si/speed.h>
+    #include <units/isq/si/international/speed.h>
     #include <units/quantity_io.h>
     #include <iostream>
 
-    using namespace units::physical;
+    using namespace units::isq;
 
     constexpr Speed auto avg_speed(Length auto d, Time auto t)
     {
@@ -52,8 +52,8 @@ of basic library features::
 
     int main()
     {
-      using namespace units::physical::si::literals;
-      using namespace units::physical::si::unit_constants;
+      using namespace units::isq::si::literals;
+      using namespace units::isq::si::unit_constants;
 
       constexpr Speed auto v1 = 110 * km / h;
       constexpr Speed auto v2 = avg_speed(220_q_km, 2_q_h);

docs/reference/systems.rst

@@ -9,7 +9,7 @@ Systems
 .. toctree::
     :maxdepth: 2
 
-    systems/physical
+    systems/isq
 
 .. toctree::
     :maxdepth: 1

docs/reference/systems/isq.rst

@@ -1,5 +1,5 @@
-Physical
-========
+International System of Quantities (ISQ)
+========================================
 
 .. toctree::
     :maxdepth: 2

docs/reference/systems/isq/si.rst

@@ -1,5 +1,5 @@
-SI
-==
+International System of Units (SI)
+==================================
 
 .. toctree::
     :maxdepth: 2

docs/use_cases.rst

@@ -6,7 +6,7 @@ Use Cases
     For brevity all the code examples in this chapter assume::
 
         using namespace units;
-        using namespace units::physical;
+        using namespace units::isq;
 
 .. toctree::
     :maxdepth: 1

docs/use_cases/extensions.rst

@@ -57,7 +57,7 @@ Enabling a Unit for Prefixing
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 In case I decide it is reasonable to express my desks with SI prefixes the only thing I have
-to change in the above code is to replace `no_prefix` with `physical::si::prefix`::
+to change in the above code is to replace `no_prefix` with `isq::si::prefix`::
 
     struct desk : named_scaled_unit<desk, "desk", si::prefix, ratio(3, 10), si::square_metre> {};
 
@@ -231,8 +231,8 @@ different systems:
 
     namespace si {
 
-    struct metre : named_unit<metre, "m", units::physical::si::prefix> {};
-    struct kilometre : prefixed_unit<kilometre, units::physical::si::kilo, metre> {};
+    struct metre : named_unit<metre, "m", units::isq::si::prefix> {};
+    struct kilometre : prefixed_unit<kilometre, units::isq::si::kilo, metre> {};
 
     struct dim_length : base_dimension<"L", metre> {};