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xo-unit ++ docs ++ quantity arithmetic + example

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Roland Conybeare 2024-05-23 14:44:00 -04:00
commit b0ce5eaee9
34 changed files with 713 additions and 173 deletions
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6
docs/CMakeLists.txt
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@ -3,8 +3,8 @@
xo_doxygen_collect_deps()
xo_docdir_doxygen_config()
xo_docdir_sphinx_config(
index.rst examples.rst glossary.rst install.rst implementation.rst development.rst
quantity-reference.rst quantity-class.rst quantity-factoryfunctions.rst quantity-unitvars.rst
index.rst examples.rst glossary.rst install.rst implementation.rst
quantity-reference.rst quantity-class.rst quantity-factoryfunctions.rst quantity-unitvars.rst quantity-source-code.rst
xquantity-reference.rst xquantity-class.rst
scaled-unit-reference.rst scaled-unit-class.rst scaled-unit-constants.rst
natural-unit-class.rst
@ -12,5 +12,7 @@ xo_docdir_sphinx_config(
bu-store-class.rst basis-unit-reference.rst
basis-unit-class.rst basis-unit-constants.rst
dimension-enum.rst
development.rst
ubuntu-github-workflow.rst
)
#xo_utest_coverage_config2()

2
docs/basis-unit-class.rst
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@ -22,7 +22,7 @@ Context
+----------------+ |
| bu_store | |
+----------------+---------------+
|cYEL basis_unit |
|cBLU basis_unit |
+--------------------------------+
| dimension |
+--------------------------------+

2
docs/basis-unit-constants.rst
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@ -22,7 +22,7 @@ Context
+----------------+ |
| bu_store | |
+----------------+---------------+
|cYEL basis_unit |
|cBLU basis_unit |
+--------------------------------+
| dimension |
+--------------------------------+

2
docs/basis-unit-reference.rst
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@ -19,7 +19,7 @@ Built-in named units for each native dimension
+----------------+ |
| bu_store | |
+----------------+---------------+
|cYEL basis_unit |
|cBLU basis_unit |
+--------------------------------+
| dimension |
+--------------------------------+

2
docs/bpu-class.rst
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@ -18,7 +18,7 @@ Context
+--------------------------------+
| natural_unit |
+--------------------------------+
|cYEL bpu |
|cBLU bpu |
+----------------+ |
| bu_store | |
+----------------+---------------+

2
docs/bu-store-class.rst
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@ -15,7 +15,7 @@ Basis Unit Store
+--------------------------------+
| bpu |
+----------------+ |
|cYEL bu_store | |
|cBLU bu_store | |
+----------------+---------------+
| basis_unit |
+--------------------------------+

1
docs/conf.py
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@ -15,6 +15,7 @@ author = 'Roland Conybeare'
#extensions = []
extensions = [ "breathe",
"sphinx.ext.mathjax", # inline math
"sphinx.ext.autodoc", # generate info from docstrings
"sphinxcontrib.ditaa", # diagrams-through-ascii-art
"sphinxcontrib.plantuml" # text -> uml diagrams

2
docs/dimension-enum.rst
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@ -24,7 +24,7 @@ Context
+----------------+---------------+
| basis_unit |
+--------------------------------+
|cYEL dimension |
|cBLU dimension |
+--------------------------------+
Introduction

39
docs/glossary.rst
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@ -4,26 +4,35 @@ Glossary
--------
.. glossary::
basis dimension
Orthogonal directions associated with basis units, for example *mass*, *length*, *time*.
In xo-unit these are represented by the enum ``xo::qty::dim``.
dimension
dim
| Fundamental, orthogonal directions associated available for constructing units.
| For example *mass*, *length*, *time*.
| In *xo-unit* these are represented by the enum :doc:`xo::qty::dimension<dimension-enum>`.
basis unit (bu)
An implementation type representing a quantity (with associated scale) in the direction of a single :term:`basis dimension`.
For example *milliseconds*, *seconds*, and *hours* stand for different basis units with the *time* dimension.
In xo-unit these are represented by the template type ``xo::qty::basis_unit``.
basis unit
bu
| An implementation type representing a quantity (with associated scale) in the direction of a single :term:`dimension`.
| For example *milliseconds*, *seconds*, and *hours* stand for different basis units within the *time* dimension.
| In *xo-unit* these are represented by the template type :doc:`xo::qty::basis_unit<basis-unit-class>`.
basis power unit
bpu
A rational power of a (single) basis unit. For example *s\ :sup:-2* or *hr\ :sup:-(1/2)*.
In xo-unit these are represented by the template type ``xo::qty::bpu``.
| A rational power of a (single) basis unit.
| For example :math:`s^{-2}` for unit "per second squared" or :math:`yr^{-(1/2)}` for "per square-root of a year".
| In *xo-unit* these are represented by the template type :doc:`xo::qty::bpu<bpu-class>`
natural unit (nu)
A cartesian product of basis power units (bpus). For example *kg.m.s\ :sup:-2* or *hr\ :sup:-(1/2)*.
In xo-unit these are represented by template type ``xo::qty::natural_unit``.
natural unit
nu
| A cartesian product of basis power units (bpus);
| For example :math:`kg.m.s^{-2}` or :math:`hr^{-(1/2)}`.
| In *xo-unit* these are represented by template type :doc:`xo::qty::natural_unit<natural-unit-class>`.
scaled unit (su)
A dimensionless multiple of a natural unit. Used as intermediate value when coalescing quantities involving different units.
In xo-unit these are represented by template type ``xo::qty::scaled_unit``.
scaled unit
su
| A dimensionless multiple of a natural unit.
| Used as intermediate value when coalescing quantities involving different units.
| In *xo-unit* these are represented by template type :doc:`xo::qty::scaled_unit<scaled-unit-class>`.
XO
A set of integrated c++ libraries for complex event processing, with browser and python integration.

37
docs/implementation.rst
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@ -3,7 +3,7 @@
Components
==========
Library dependencies for *xo-unit*:
Library dependency tower for *xo-unit*:
.. ditaa::
@ -14,28 +14,31 @@ Library dependencies for *xo-unit*:
+-----------------+
| xo_flatstring |
+-----------------+
| xo_cmake |
+-----------------+
``xo-unit`` also depends on ``xo-cmake`` macros.
Install instructions :doc:`here<install>`
Abstraction tower for *xo-unit* components:
.. ditaa::
:--scale: 0.85
+-----------+-----------+
| quantity | xquantity |
+-----------+-----------+
| scaled_unit |
+-----------------------+
| natural_unit |
+-----------------------+
| bpu |
+-----------+ |
| bu_store | |
+-----------+-----------+
| basis_unit |
+-----------------------+
| dimension |
+-----------------------+
+----------------+---------------+
| quantity | xquantity |
+----------------+---------------+
| scaled_unit |
+--------------------------------+
| natural_unit |
+--------------------------------+
| bpu |
+----------------+ |
| bu_store | |
+----------------+---------------+
| basis_unit |
+--------------------------------+
| dimension |
+--------------------------------+
- :doc:`quantity<quantity-reference>`:

13
docs/index.rst
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@ -28,7 +28,7 @@ runtime (since we can't construct new c++ types at runtime).
.. toctree::
:maxdepth: 2
:caption: xo-unit contents:
:caption: xo-unit contents
install
examples
@ -42,10 +42,7 @@ runtime (since we can't construct new c++ types at runtime).
basis-unit-reference
dimension-enum
development
Indices and Tables
------------------
* :ref:`glossary`
* :ref:`genindex`
* :ref:`search`
ubuntu-github-workflow
glossary
genindex
search

47
docs/install.rst
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@ -7,26 +7,35 @@ Install
=======
``xo-unit`` uses supporting header-only libraries ``xo-ratio`` and ``xo-flatstring``.
All three are on github:
and (optionally) cmake macros ``xo-cmake``. These are on github:
- `xo-unit source`_
- `xo-ratio source`_
- `xo-flatstring source`_
- `xo-unit source`_ (constexpr quantities, units and dimension-checking)
- `xo-ratio source`_ (constexpr exact ratios)
- `xo-flatstring source`_ (constexpr strings)
- `xo-cmake source`_ (shared cmake macros)
.. _xo-unit source: https://github.com/rconybea/xo-unit
.. _xo-ratio source: https://github.com/rconybea/xo-ratio
.. _xo-flatstring source: https://github.com/rconybea/xo-flatstring
.. _xo-cmake source: https://github.com/rconybea/xo-cmake
`xo-cmake` is nccessary to invoke `xo` cmake build for:
- site install
- example programs
- unit tests
Can omit to instead copy `xo_unit`, `xo-ratio` and `xo-flatstring` source trees;
see instructions below for including as git submodule
Implementation relies on some c++20 features (for example class-instances as template arguments).
Tested with gcc 12.3, 13.2
``xo-unit`` also relies on sister header-only libraries:
One way to use ``xo-unit`` in a project is to import the source tree directly:
Include as submodule
--------------------
One way to use ``xo-unit`` in a project is to import the source tree directly:
.. code-block:: bash
cd myproject
@ -50,21 +59,18 @@ to c++ source files that rely on xo-unit
Ubuntu Install Pattern
----------------------
Example instructions (from github actions CI) for build starting from stock ubuntu are in `ubuntu-main.yml`_
.. _ubuntu-main.yml: https://github.com/Rconybea/xo-unit/blob/main/.github/workflows/ubuntu-main.yml
:doc:`Example instructions<ubuntu-github-workflow>` (used for github actions CI) for build starting from stock ubuntu
Installing from source
----------------------
Although the xo-unit, xo-ratio and xo-flatstring libraries are header-only,
they do have a build dependency on shared cmake macros, and a bootstrap script `xo-cmake-config`.
Install scripts for `xo-unit`, `xo-ratio` and `xo-flatstring` depend on shared cmake macros
and a bootstrap script `xo-cmake-config`.
* `xo-cmake`_ source
.. _xo-cmake: https://github.com/rconybea/xo-cmake
Preamble:
.. code-block:: bash
@ -183,7 +189,7 @@ Preamble:
git clone https://github.com/rconybea/xo-unit
PREFIX=~/local # ..or other desired installation prefix
Build and Install `catch2` (assuming ubuntu here):
.. code-block:: bash
@ -216,7 +222,7 @@ Build and Install `xo-randomgen` (no unit tests yet):
cmake --build xo-randomgen/.build -j
cmake --install xo-randomgen/.build
Build, Test and Install `xo-flatstring`:
Build, Test and Install `xo-flatstring`:
.. code-block:: bash
@ -255,7 +261,7 @@ To enable building example programs:
cd ~/proj/xo
cmake -DCMAKE_INSTALL_PREFIX=$PREFIX -DXO_ENABLE_EXAMPLES=1 -B xo-unit/.build -S xo-unit
Run examples from the build directory:
.. code-block:: bash
@ -288,17 +294,16 @@ Preamble (assuming ubuntu here):
sudo apt-get install python3-sphinx-rtd-theme
sudo apt-get install python3-breathe
Build `xo-unit` docs
Build `xo-unit` docs
.. code-block:: bash
cd ~/proj/xo
cmake -DCMAKE_INSTALL_PREFIX=$PREFIX -B xo-unit/.build
cmake --build xo-unit/.build -- docs
cmake --build xo-unit/.build -- docs
cmake --install xo-unit/.build # if docs built, installs to $PREFIX/share/doc/xo_unit/html
Supported compilers
-------------------
* developed with gcc 12.3.0 and gcc 13.2.0; github CI using gcc 11.4.0 (asof March 2024)

2
docs/natural-unit-class.rst
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@ -16,7 +16,7 @@ Context
+----------------+---------------+
| scaled_unit |
+--------------------------------+
|cYEL natural_unit |
|cBLU natural_unit |
+--------------------------------+
| bpu |
+----------------+ |

51
docs/quantity-class.rst
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@ -3,10 +3,16 @@
Quantity
========
Dimensioned quantity with compile-time unit checking/conversion
Context
-------
.. ditaa::
:--scale: 0.85
+----------------+---------------+
|cYEL quantity | xquantity |
|cBLU quantity | xquantity |
+----------------+---------------+
| scaled_unit |
+--------------------------------+
@ -36,15 +42,37 @@ Quantity
rectangle constexpr #e0f0ff {
object unit<<natural_unit>>
object unit<<scaled_unit>>
unit : is_natural() = true
qty1 o-- unit : s_unit (static constexpr)
qty1 o-- unit : s_scaled_unit (static constexpr)
}
Arithmetic on :doc:`xo::qty::quantity<quantity-reference>` instances
does *not* use ``xo::qty::quantity::s_scaled_unit`` at runtime;
instead gets everything it needs at compile time.
- Arithmetic on :doc:`xo::qty::quantity<quantity-reference>` instances
does *not* use ``xo::qty::quantity::s_scaled_unit`` at runtime;
instead gets everything it needs at compile time.
- The :code:`xo::qty::quantity` template takes a :doc:`xo::qty::scaled_unit<scaled-unit-class>` instance,
but only accepts values with :code:`xo::qty::scaled_unit::is_natural() == true`.
This accomodation (instead of requiring a :doc:`xo::qty::natural_unit<natural-unit-class>` instance
is to make possible code like this possible:
.. code-block:: cpp
#include "xo/unit/quantity.hpp"
using namespace xo::qty;
quantity<u::meter / u::second> x;
quantity<u::meter * u::mter> y;
while rejecting attempt to mix multiple scales in the same quantity value:
.. code-block:: cpp
quantity<u::meter * u::millimeter> x; // will not compile
Class
-----
@ -81,19 +109,16 @@ Assignment
----------
.. doxygengroup:: quantity-assignment
:content-only:
Access Methods
--------------
.. doxygengroup:: quantity-access-methods
:content-only:
Constants
---------
.. doxygengroup:: quantity-constants
:content-only:
Conversion Methods
------------------
@ -101,13 +126,11 @@ Conversion Methods
Amount-preserving conversion to quantities with different units and/or representation.
.. doxygengroup:: quantity-unit-conversion
:content-only:
Arithmetic
----------
Arithmetic Operators
--------------------
.. doxygengroup:: quantity-arithmetic
:content-only:
.. doxygengroup:: quantity-operators
Support methods for arithmetic operations

15
docs/quantity-factoryfunctions.rst
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@ -1,9 +1,18 @@
.. _quantity_factoryfunctions:
Quantity Factory Functions
==========================
Convenience functions for creating quantities with compile-time units
Context
-------
.. ditaa::
:--scale: 0.85
+----------------+---------------+
|cYEL quantity | xquantity |
|cBLU quantity | xquantity |
+----------------+---------------+
| scaled_unit |
+--------------------------------+
@ -21,8 +30,8 @@
.. toctree::
:maxdepth: 2
Quantity Factory Functions
==========================
Introduction
------------
.. code-block:: cpp

4
docs/quantity-reference.rst
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@ -4,9 +4,10 @@ Quantity Reference
==================
.. ditaa::
:--scale: 0.85
+----------------+---------------+
|cYEL quantity | xquantity |
|cBLU quantity | xquantity |
+----------------+---------------+
| scaled_unit |
+--------------------------------+
@ -27,3 +28,4 @@ Quantity Reference
quantity-class
quantity-factoryfunctions
quantity-unitvars
quantity-source-code

11
docs/quantity-source-code.rst Normal file
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@ -0,0 +1,11 @@
.. _quantity-source-code:
Quantity Source Code
====================
github: `quantity.hpp @github.com`_
.. _`quantity.hpp @github.com`: https://github.com/rconybea/xo-unit/blob/main/include/xo/unit/quantity.hpp
.. literalinclude:: ../include/xo/unit/quantity.hpp
:language: c++

59
docs/quantity-unitvars.rst
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@ -1,11 +1,35 @@
.. _quantity-unitvars:
.. toctree::
:maxdepth: 2
Quantity Unit Variables
=======================
Built-in unit quantities
Context
-------
.. ditaa::
:--scale: 0.85
+----------------+---------------+
|cBLU quantity | xquantity |
+----------------+---------------+
| scaled_unit |
+--------------------------------+
| natural_unit |
+--------------------------------+
| bpu |
+----------------+ |
| bu_store | |
+----------------+---------------+
| basis_unit |
+--------------------------------+
| dimension |
+--------------------------------+
Introduction
------------
.. code-block:: cpp
#include <xo/unit/quantity.hpp>
@ -28,11 +52,16 @@ Can use these to assemble unit quantities with compound dimensions
Mass
----
.. doxygenvariable:: xo::qty::qty::picogram
.. doxygenvariable:: xo::qty::qty::nanogram
.. doxygenvariable:: xo::qty::qty::microgram
.. doxygenvariable:: xo::qty::qty::milligram
.. doxygenvariable:: xo::qty::qty::gram
.. doxygenvariable:: xo::qty::qty::kilogram
.. doxygenvariable:: xo::qty::qty::tonne
.. doxygenvariable:: xo::qty::qty::kilotonne
.. doxygenvariable:: xo::qty::qty::megatonne
.. doxygenvariable:: xo::qty::qty::gigatonne
Distance
--------
@ -46,20 +75,24 @@ Distance
.. doxygenvariable:: xo::qty::qty::gigameter
.. doxygenvariable:: xo::qty::qty::lightsecond
.. doxygenvariable:: xo::qty::qty::astronomicalunit
.. doxygenvariable:: xo::qty::qty::inch
.. doxygenvariable:: xo::qty::qty::foot
.. doxygenvariable:: xo::qty::qty::yard
.. doxygenvariable:: xo::qty::qty::mile
Time
----
.. notyet .. doxygenvariable:: xo::qty::qty::picosecond
.. notyet .. doxygenvariable:: xo::qty::qty::nanosecond
.. notyet .. doxygenvariable:: xo::qty::qty::microsecond
.. notyet .. doxygenvariable:: xo::qty::qty::millisecond
.. doxygenvariable:: xo::qty::qty::picosecond
.. doxygenvariable:: xo::qty::qty::nanosecond
.. doxygenvariable:: xo::qty::qty::microsecond
.. doxygenvariable:: xo::qty::qty::millisecond
.. doxygenvariable:: xo::qty::qty::second
.. doxygenvariable:: xo::qty::qty::minute
.. doxygenvariable:: xo::qty::qty::hour
.. doxygenvariable:: xo::qty::qty::day
.. notyet doxygenvariable:: xo::qty::qty::week
.. notyet doxygenvariable:: xo::qty::qty::month
.. notyet doxygenvariable:: xo::qty::qty::year
.. notyet doxygenvariable:: xo::qty::qty::year250
.. notyet doxygenvariable:: xo::qty::qty::year360
.. notyet doxygenvariable:: xo::qty::qty::year365
.. doxygenvariable:: xo::qty::qty::week
.. doxygenvariable:: xo::qty::qty::month
.. doxygenvariable:: xo::qty::qty::year
.. doxygenvariable:: xo::qty::qty::year250
.. doxygenvariable:: xo::qty::qty::year360
.. doxygenvariable:: xo::qty::qty::year365

2
docs/scaled-unit-class.rst
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@ -14,7 +14,7 @@ Context
+----------------+----------------+
| quantity | xquantity |
+----------------+----------------+
|cYEL scaled_unit |
|cBLU scaled_unit |
+---------------------------------+
| natural_unit |
+---------------------------------+

4
docs/scaled-unit-constants.rst
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@ -3,7 +3,7 @@
Scaled Unit Constants
=====================
Built-in unit constants.
Built-in unit constants, for use with conversions
Context
-------
@ -14,7 +14,7 @@ Context
+----------------+---------------+
| quantity | xquantity |
+----------------+---------------+
|cYEL scaled_unit |
|cBLU scaled_unit |
+--------------------------------+
| natural_unit |
+--------------------------------+

2
docs/scaled-unit-reference.rst
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@ -11,7 +11,7 @@ A dimensionless multiple of a :doc:`natural_unit<natural-unit-class>`
+----------------+---------------+
| quantity | xquantity |
+----------------+---------------+
|cYEL scaled_unit |
|cBLU scaled_unit |
+--------------------------------+
| natural_unit |
+--------------------------------+

9
docs/ubuntu-github-workflow.rst Normal file
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@ -0,0 +1,9 @@
.. ubuntu-github-workflow:
Ubuntu Github Workflow
======================
Instructions for build starting on a stock ubuntu platform (see `xo-unit/.github/workflows/ubuntu_main.yml`)
.. literalinclude:: ../.github/workflows/ubuntu-main.yml
:language: yaml

60
docs/xquantity-class.rst
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@ -3,13 +3,73 @@
Xquantity
=========
Polymorphic dimensioned quantity with runtime unit checking/conversion
Context
-------
.. ditaa::
:--scale: 0.85
+----------------+---------------+
| quantity |cBLU xquantity |
+----------------+---------------+
| scaled_unit |
+--------------------------------+
| natural_unit |
+--------------------------------+
| bpu |
+----------------+ |
| bu_store | |
+----------------+---------------+
| basis_unit |
+--------------------------------+
| dimension |
+--------------------------------+
.. code-block:: cpp
#include <xo/unit/xquantity.hpp>
.. uml::
:scale: 99%
:align: center
allowmixing
object qty1<<xquantity>>
qty1 : scale = 1.23
qty1 : unit = unit
object unit<<scaled_unit>>
unit : is_natural() = true
qty1 o-- unit
Class
-----
Class with run-time unit representation.
.. doxygenclass:: xo::qty::xquantity
Member Variables
----------------
.. doxygengroup:: xquantity-instance-vars
Constructors
------------
.. doxygengroup:: xquantity-ctors
Access Methods
--------------
.. doxygengroup:: xquantity-access-methods
General Methods
---------------
.. doxygengroup:: xquantity-methods

3
docs/xquantity-reference.rst
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@ -4,9 +4,10 @@ Xquantity Reference
===================
.. ditaa::
:--scale: 0.85
+----------------+---------------+
| quantity |cYEL xquantity |
| quantity |cBLU xquantity |
+----------------+---------------+
| scaled_unit |
+--------------------------------+

1
example/CMakeLists.txt
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@ -7,3 +7,4 @@ add_subdirectory(ex6)
add_subdirectory(ex7)
add_subdirectory(ex8)
add_subdirectory(ex_su)
add_subdirectory(ex_qty)

14
example/ex8/ex8.cpp
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@ -8,11 +8,12 @@ int
main () {
using namespace xo::qty;
namespace u = xo::qty::u;
//namespace q = xo::qty::qty;
using namespace std;
xquantity qty1(7, u::foot);
xquantity qty2(6.0, u::inch);
constexpr xquantity qty1(7, u::foot);
constexpr xquantity qty2(6.0, u::inch);
// constexpr not supported for xquantity addition
xquantity qty3 = qty1 + qty2;
cerr << "qty1: " << qty1 << endl;
@ -24,6 +25,13 @@ main () {
/* 2286mm */
cerr << "res: " << res << endl;
/* 12 */
xquantity qty4 = qty1 / qty2;
auto res2 = qty4 + 4;
cerr << "res2: " << res << endl;
}
/** end ex8.cpp */

12
example/ex_qty/CMakeLists.txt Normal file
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@ -0,0 +1,12 @@
# xo-unit/example/ex_qty/CMakeLists.txt
set(SELF_EXE xo_unit_ex_qty)
set(SELF_SRCS ex_qty.cpp)
if (XO_ENABLE_EXAMPLES)
xo_add_executable(${SELF_EXE} ${SELF_SRCS})
xo_self_headeronly_dependency(${SELF_EXE} xo_unit)
xo_dependency(${SELF_EXE} xo_flatstring)
endif()
# end CMakeLists.txt

18
example/ex_qty/ex_qty.cpp Normal file
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@ -0,0 +1,18 @@
/* @file ex_qty.cpp */
#include "xo/unit/quantity.hpp"
#include "xo/unit/quantity_iostream.hpp"
using namespace std;
int
main() {
using namespace xo::qty;
namespace u = xo::qty::u;
static_assert(u::meter.n_bpu() == 1);
//constexpr auto q = qty::meters(2) + u::meter;
}
/* end ex_qty.cpp */

2
include/xo/unit/mpl/quantity.hpp
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@ -399,7 +399,7 @@ namespace xo {
}
///@}
/** @defgroup quantity-arithmetic **/
/** @defgroup mpl-quantity-arithmetic **/
///@{
/** @brief add quantity in-place
*

281
include/xo/unit/quantity.hpp
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@ -8,6 +8,7 @@
#include "quantity_ops.hpp"
#include "natural_unit.hpp"
#include "scaled_unit.hpp"
#include "scaled_unit_concept.hpp"
namespace xo {
namespace qty {
@ -70,22 +71,40 @@ namespace xo {
/** @defgroup quantity-access-methods quantity access methods **/
///@{
/** @brief value of @c scale_ in quantity representing amount (@c scale_ * @c s_unit) **/
constexpr const repr_type & scale() const { return scale_; }
/** @brief s_unit in quantity representing amount (@c scale_ * @c s_unit) **/
constexpr const unit_type & unit() const { return s_scaled_unit; }
/** @brief true iff this quantity represents a dimensionless value **/
constexpr bool is_dimensionless() const {
static constexpr bool is_dimensionless() {
return s_scaled_unit.is_dimensionless();
}
///@}
// unit_qty
// zero_qty
/** abbreviated suffix for quantities with this unit **/
constexpr nu_abbrev_type abbrev() const {
return s_scaled_unit.natural_unit_.abbrev();
}
///@}
/** @defgroup quantity-arithmetic-support **/
///@{
/** create unit quantity with same unit as @c this **/
constexpr
auto unit_qty() const {
return quantity<s_scaled_unit, repr_type>(1);
}
/** create zero quantity with same unit as @c this **/
constexpr
auto zero_qty() const {
return quantity<s_scaled_unit, repr_type>(0);
}
constexpr
auto reciprocal() const {
return quantity<s_scaled_unit.reciprocal(),
@ -159,6 +178,9 @@ namespace xo {
}
///@}
/** @addtogroup quantity-arithmetic-support **/
///@{
/** create quantity representing this amount multiplied by dimensionless value @p x
*
* @pre x must be an arithmetic type such as @c int or @c double
@ -171,15 +193,36 @@ namespace xo {
return quantity<s_scaled_unit, r_repr_type>(x * this->scale_);
}
// divide_by
// divide_into
/** create quantity representing this quantity divided by dimensionless value @p x
*
* @pre x must be an arithmetic type such as @c int or @c double
**/
template <typename Dimensionless>
requires std::is_arithmetic_v<Dimensionless>
constexpr auto divide_by(Dimensionless x) const {
using r_repr_type = std::common_type_t<repr_type, Dimensionless>;
// divide
// add
// subtract
return quantity<s_scaled_unit, r_repr_type>(this->scale_ / x);
}
/** create quantity representing dimensionless value @x divided by this quantity
*
* @pre x must be an arithmetic type such as @c int or @c double
**/
template <typename Dimensionless>
requires std::is_arithmetic_v<Dimensionless>
constexpr auto divide_into(Dimensionless x) const {
using r_repr_type = std::common_type_t<repr_type, Dimensionless>;
return quantity(static_cast<r_repr_type>(x) / this->scale_,
s_scaled_unit.reciprocal());
}
///@}
/** @defgroup quantity-comparison-support **/
///@{
/** compare two @c quantity instances, under three-way comparison **/
template <typename Quantity2>
static constexpr
@ -188,18 +231,43 @@ namespace xo {
return x.scale() <=> y2.scale();
}
///@}
// operator-
// operator+=
// operator-=
/** @defgroup quantity-operators **/
///@{
/** unary negation; preserves unit information **/
quantity operator-() const {
return quantity(-scale_);
}
/** add @p y in-place, converting units if necessary **/
template <typename Quantity2>
constexpr
quantity & operator+=(const Quantity2 & y) {
quantity y2 = y.template rescale_ext<s_scaled_unit>();
this->scale_ += y2.scale();
return *this;
}
/** subtract @p y in-place, converting units if necessary **/
template <typename Quantity2>
constexpr
quantity & operator-=(const Quantity2 & y) {
quantity y2 = y.template rescale_ext<s_scaled_unit>();
this->scale_ -= y2.scale();
return *this;
}
// operator*=
// operator/=
/** **/
constexpr nu_abbrev_type abbrev() const {
return s_scaled_unit.natural_unit_.abbrev();
}
///@}
/** @defgroup quantity-assignment quantity assignment operators **/
///@{
@ -429,6 +497,9 @@ namespace xo {
return x.template with_repr<Repr2>();
}
/** @addtogroup quantity-operators **/
///@{
/** note: won't have constexpr result w/ fractional dimension until c++26 (when ::sqrt(), ::pow() are constexpr)
**/
template <typename Q1, typename Q2>
@ -442,7 +513,27 @@ namespace xo {
return detail::quantity_util::multiply(x, y);
}
/** note: won't have constexpr result w/ fractional dimension until c++26 (when ::sqrt(), ::pow() are constexpr)
/** note: does not require unit scaling, so constexpr with c++23 **/
template <typename Dimensionless, typename Quantity>
requires std::is_arithmetic_v<Dimensionless> && quantity_concept<Quantity>
constexpr auto
operator* (const Quantity & x, Dimensionless y)
{
return x.scale_by(y);
}
/** note: does not require unit scaling, so constexpr with c++23 **/
template <typename Dimensionless, typename Quantity>
requires std::is_arithmetic_v<Dimensionless> && quantity_concept<Quantity>
constexpr auto
operator* (Dimensionless x, const Quantity & y)
{
return y.scale_by(x);
}
/** divide quantity @p x by quantity @p y.
*
* note: won't have constexpr result w/ fractional dimension until c++26 (when ::sqrt(), ::pow() are constexpr)
**/
template <typename Q1, typename Q2>
requires (quantity_concept<Q1>
@ -455,7 +546,30 @@ namespace xo {
return detail::quantity_util::divide(x, y);
}
/** note: won't have constexpr result w/ fractional dimension until c++26 (when ::sqrt(), ::pow() are constexpr)
/** divide quantity @p x by dimensionless value @p y **/
template <typename Dimensionless, typename Quantity>
requires std::is_arithmetic_v<Dimensionless> && quantity_concept<Quantity>
constexpr auto
operator/ (const Quantity & x, Dimensionless y)
{
return x.divide_by(y);
}
/** divide dimensionless value @p x by quantity @p y **/
template <typename Dimensionless, typename Quantity>
requires std::is_arithmetic_v<Dimensionless> && quantity_concept<Quantity>
constexpr auto
operator/ (Dimensionless x, const Quantity & y)
{
return y.divide_into(x);
}
/** add quantity @p y to quantity @p x. Result will have the same units as @p x.
* Representation will be the widest of {@c x::repr_type, @c y::repr_type}.
*
* note: won't have constexpr result w/ fractional dimension until c++26 (when ::sqrt(), ::pow() are constexpr)
*
* @pre @p x and @p y expected to have consistent dimensions
**/
template <typename Q1, typename Q2>
requires (quantity_concept<Q1>
@ -468,7 +582,46 @@ namespace xo {
return detail::quantity_util::add(x, y);
}
/** note: won't have constexpr result w/ fractional dimension until c++26 (when ::sqrt(), ::pow() are constexpr)
/** subtract an arithmetic value from a dimensionless quantity **/
template <typename Quantity,
typename Dimensionless>
requires (quantity_concept<Quantity>
&& Quantity::is_dimensionless()
&& std::is_arithmetic_v<Dimensionless>)
constexpr auto
operator+ (const Quantity & x, Dimensionless y)
{
using repr_type = std::common_type_t<typename Quantity::repr_type, Dimensionless>;
auto xp = static_cast<repr_type>(x.scale());
auto yp = static_cast<repr_type>(y);
return xp + yp;
}
/** subtract a dimensionless quantity from an arithmetic value **/
template <typename Dimensionless,
typename Quantity>
requires (std::is_arithmetic_v<Dimensionless>
&& quantity_concept<Quantity>
&& Quantity::is_dimensionless())
constexpr auto
operator+ (Dimensionless x, const Quantity & y)
{
using repr_type = std::common_type_t<Dimensionless, typename Quantity::repr_type>;
auto xp = static_cast<repr_type>(x);
auto yp = static_cast<repr_type>(y.scale());
return xp + yp;
}
/** subtract quantity @p y from quantity @p x. Result will have the same units as @p x.
* Representation will be the widest of {@c x::repr_type, @c y::repr_type}
*
* note: won't have constexpr result w/ fractional dimension until c++26 (when ::sqrt(), ::pow() are constexpr)
*
* @pre @p x and @p y expected to have consistent dimensions
**/
template <typename Q1, typename Q2>
requires (quantity_concept<Q1>
@ -481,6 +634,8 @@ namespace xo {
return detail::quantity_util::subtract(x, y);
}
///@}
namespace qty {
// ----- mass -----
@ -528,22 +683,26 @@ namespace xo {
namespace qty {
// ----- mass constants ----
/** @brief a quantity representing 1 picogram of mass, with compile-time unit representation **/
/** a quantity representing 1 picogram of mass, with compile-time unit representation **/
static constexpr auto picogram = picograms(1);
/** @brief a quantity representing 1 nanogram of mass, with compile-time unit representation **/
/** a quantity representing 1 nanogram of mass, with compile-time unit representation **/
static constexpr auto nanogram = nanograms(1);
/** @brief a quantity representing 1 microgram of mass, with compile-time unit representation **/
/** a quantity representing 1 microgram of mass, with compile-time unit representation **/
static constexpr auto microgram = micrograms(1);
/** @brief a quantity representing 1 milligram of mass, with compile-time unit representation **/
/** a quantity representing 1 milligram of mass, with compile-time unit representation **/
static constexpr auto milligram = milligrams(1);
/** @brief a quantity representing 1 gram of mass, with compile-time unit representation **/
/** a quantity representing 1 gram of mass, with compile-time unit representation **/
static constexpr auto gram = grams(1);
/** @brief a quantity representing 1 kilogram of mass, with compile-time unit representation **/
/** a quantity representing 1 kilogram of mass, with compile-time unit representation **/
static constexpr auto kilogram = kilograms(1);
/** @brief a quantity representing 1 metric tonne of mass, with compile-time unit representation **/
/** a quantity representing 1 metric tonne of mass, with compile-time unit representation **/
static constexpr auto tonne = tonnes(1);
/** @brief a quantity representing 1 metric kilotonne of mass, with compile-time unit representation **/
/** a quantity representing 1 metric kilotonne of mass, with compile-time unit representation **/
static constexpr auto kilotonne = kilotonnes(1);
/** a quantity representing 1 metric megatonne of mass, with compile-time unit representation **/
static constexpr auto megatonne = megatonnes(1);
/** a quantity representing 1 metric gigatonne of mass, with compile-time unit representation **/
static constexpr auto gigatonne = gigatonnes(1);
} /*namespace qty*/
namespace qty {
@ -618,22 +777,37 @@ namespace xo {
static constexpr auto nanometer = nanometers(1);
/** a quantity representing 1 micrometer of distance, with compile-time unit representation **/
static constexpr auto micrometer = micrometers(1);
/** @brief a quantity representing 1 millimeter of distance, with compile-time unit representation **/
/** a quantity representing 1 millimeter of distance, with compile-time unit representation **/
static constexpr auto millimeter = millimeters(1);
/** @brief a quantity representing 1 meter of distance, with compile-time unit representation **/
/** a quantity representing 1 meter of distance, with compile-time unit representation **/
static constexpr auto meter = meters(1);
/** @brief a quantity representing 1 kilometer of distance, with compile-time unit representation **/
/** a quantity representing 1 kilometer of distance, with compile-time unit representation **/
static constexpr auto kilometer = kilometers(1);
/** @brief a quantity representing 1 megameter of distance, with compile-time unit representation **/
/** a quantity representing 1 megameter of distance, with compile-time unit representation **/
static constexpr auto megameter = megameters(1);
/** @brief a quantity representing 1 gigameter of distance, with compile-time unit representation **/
/** a quantity representing 1 gigameter of distance, with compile-time unit representation **/
static constexpr auto gigameter = gigameters(1);
/** @brief a quantity representing exactly 1 lightsecond of distance, with compile-time unit representation **/
/** a quantity representing exactly 1 lightsecond of distance,
* with compile-time unit representation
**/
static constexpr auto lightsecond = lightseconds(1);
/** @brief a quantity representing exactly 1 astronomical unit of distance, with compile-time unit representation **/
/** a quantity representing exactly 1 astronomical unit of distance,
* with compile-time unit representation
**/
static constexpr auto astronomicalunit = astronomicalunits(1);
/** a quantity representing 1 inch of distance, with compile-time unit operations **/
static constexpr auto inch = inches(1);
/** a quantity representing 1 foot of distance, with compile-time unit operations **/
static constexpr auto foot = feet(1);
/** a quantity representing 1 yard of distance, with compile-time unit operations **/
static constexpr auto yard = yards(1);
/** a quantity representing 1 mile of distance, with compile-time unit operations **/
static constexpr auto mile = miles(1);
} /*namespace qty*/
namespace qty {
@ -707,17 +881,48 @@ namespace xo {
namespace qty {
// ----- time constants ----
/** @brief a quantity representing 1 second of time, with compile-time unit representation **/
/** a quantity representing 1 picosecond of time, with compile-time unit representation **/
static constexpr auto picosecond = picoseconds(1);
/** a quantity representing 1 nanosecond of time, with compile-time unit representation **/
static constexpr auto nanosecond = nanoseconds(1);
/** a quantity representing 1 microsecond of time, with compile-time unit representation **/
static constexpr auto microsecond = microseconds(1);
/** a quantity representing 1 millisecond of time, with compile-time unit representation **/
static constexpr auto millisecond = milliseconds(1);
/** a quantity representing 1 second of time, with compile-time unit representation **/
static constexpr auto second = seconds(1);
/** @brief a quantity representing 1 minute of time, with compile-time unit representation **/
/** a quantity representing 1 minute of time, with compile-time unit representation **/
static constexpr auto minute = minutes(1);
/** @brief a quantity representing 1 hour of time, with compile-time unit representation **/
/** a quantity representing 1 hour of time, with compile-time unit representation **/
static constexpr auto hour = hours(1);
/** @brief a quantity representing 1 day of time (exactly 24 hours), with compile-time unit representation **/
/** a quantity representing 1 day of time (exactly 24 hours), with compile-time unit representation **/
static constexpr auto day = days(1);
/** a quantity representing 1 week of time (7 24-hour days), with compile-time unit representation **/
static constexpr auto week = weeks(1);
/** a quantity representing 1 month of time (30 24-hour days), with compile-time unit representation **/
static constexpr auto month = months(1);
/** a quantity representing 1 year of time (365.25 24-hour days), with compile-time unit representation **/
static constexpr auto year = years(1);
/** a quantity representing 1 250-day year of time, with compile-time unit representation **/
static constexpr auto year250 = year250s(1);
/** a quantity representing 1 360-day year of time, with compile-time unit representation **/
static constexpr auto year360 = year360s(1);
/** a quantity representing 1 365-day year of time, with compile-time unit representation **/
static constexpr auto year365 = year365s(1);
} /*namespace qty*/
namespace qty {

41
include/xo/unit/quantity_ops.hpp
View file

@ -9,24 +9,45 @@
namespace xo {
namespace qty {
/** note: does not require unit scaling, so constexpr with c++23 **/
template <typename Dimensionless, typename Quantity>
requires std::is_arithmetic_v<Dimensionless> && quantity_concept<Quantity>
/** @defgroup quantity-dimensionless-operators **/
///@{
/** subtract an arithmetic value from a dimensionless quantity **/
template <typename Quantity,
typename Dimensionless>
requires (quantity_concept<Quantity>
&& Quantity::is_dimensionless()
&& std::is_arithmetic_v<Dimensionless>)
constexpr auto
operator* (Dimensionless x, const Quantity & y)
operator- (const Quantity & x, Dimensionless y)
{
return y.scale_by(x);
using repr_type = std::common_type_t<typename Quantity::repr_type, Dimensionless>;
auto xp = static_cast<repr_type>(x.scale());
auto yp = static_cast<repr_type>(y);
return xp - yp;
}
/** note: does not require unit scaling, so constexpr with c++23 **/
template <typename Dimensionless, typename Quantity>
requires std::is_arithmetic_v<Dimensionless> && quantity_concept<Quantity>
/** subtract a dimensionless quantity from an arithmetic value **/
template <typename Dimensionless,
typename Quantity>
requires (std::is_arithmetic_v<Dimensionless>
&& quantity_concept<Quantity>
&& Quantity::is_dimensionless())
constexpr auto
operator* (const Quantity & x, Dimensionless y)
operator- (Dimensionless x, const Quantity & y)
{
return x.scale_by(y);
using repr_type = std::common_type_t<Dimensionless, typename Quantity::repr_type>;
auto xp = static_cast<repr_type>(x);
auto yp = static_cast<repr_type>(y.scale());
return xp - yp;
}
///@}
/** note: won't have constexpr result until c++26 (when ::sqrt(), ::pow() are constexpr)
**/
template <typename Quantity, typename Quantity2>

3
include/xo/unit/scaled_unit.hpp
View file

@ -44,6 +44,9 @@ namespace xo {
/** @defgroup scaled-unit-access-methods scaled-unit access methods **/
///@{
/** always true for scaled_unit **/
static constexpr bool is_scaled_unit_type_v = true;
/** always true for scaled_unit **/
constexpr bool is_scaled_unit_type() const { return true; }

23
include/xo/unit/scaled_unit_concept.hpp Normal file
View file

@ -0,0 +1,23 @@
/** @file scaled_unit_concept.hpp **/
#pragma once
#include <concepts>
namespace xo {
namespace qty {
template <typename ScaledUnit>
concept scaled_unit_concept = requires(ScaledUnit su)
{
typename ScaledUnit::ratio_int_type;
{ su.is_scaled_unit_type() } -> std::same_as<bool>;
{ su.is_natural() } -> std::same_as<bool>;
{ su.is_dimensionless() } -> std::same_as<bool>;
} && ScaledUnit::is_scaled_unit_type_v;
} /*namespace qty*/
} /*namespace xo*/
/** end scaled_unit_concept.hpp **/

104
include/xo/unit/xquantity.hpp
View file

@ -18,7 +18,7 @@ namespace xo {
*
* Constexpr implementation, but units are explicitly represented:
* @code
* sizeof(Quantity2) > sizeof(Repr)
* sizeof(xquantity) > sizeof(xquantity::repr_type)
* @endcode
*
* Explicit unit representation allows introducing units at runtime,
@ -32,22 +32,47 @@ namespace xo {
* - Repr supports conversion from double.
**/
template <typename Repr = double,
typename Int = std::int64_t,
typename Int2x = detail::width2x_t<Int>>
typename Int = std::int64_t>
class xquantity {
public:
/** @defgroup xquantity-type-traits xquantity type traits **/
///@{
/** @brief runtime representation for this value's scale **/
using repr_type = Repr;
/** @brief runtime representation for this value's unit **/
using unit_type = natural_unit<Int>;
/** @brief type used for numerator and denominator in basis-unit scalefactor ratios **/
using ratio_int_type = Int;
using ratio_int2x_type = Int2x;
/** @brief double-width type for numerator and denominator of intermediate
* scalefactor ratios. Use to mitigate loss of precision during computation
* of conversion factors between units with widely-differing magnitude
**/
using ratio_int2x_type = detail::width2x_t<typename unit_type::ratio_int_type>;
///@}
public:
/* zero, dimensionless */
/** @defgroup xquantity-ctors xquantity constructors **/
///@{
/** create dimensionless, zero quantity **/
constexpr xquantity()
: scale_{0}, unit_{natural_unit<Int>()} {}
/** create quantity representing multiple of @p scale times @p unit **/
constexpr xquantity(Repr scale,
const natural_unit<Int> & unit)
: scale_{scale}, unit_{unit} {}
/** create quantity representing multiple of @p scale times @p unit.
*
* Collects outer scalefactors (if any) from @p unit,
* so for example:
*
* @code
* using namespace xo::qty;
* xquantity q(123, u::meter * u::millimeter);
*
* q.scale() --> 0.123
* @endcode
**/
constexpr xquantity(Repr scale,
const scaled_unit<Int> & unit)
:
@ -59,17 +84,39 @@ namespace xo {
),
unit_{unit.natural_unit_} {}
///@}
static constexpr bool always_constexpr_unit = false;
/** @defgroup xquantity-access-methods xquantity access methods **/
///@{
/** get member @ref scale_ **/
constexpr const repr_type & scale() const { return scale_; }
/** get member @ref unit_ **/
constexpr const unit_type & unit() const { return unit_; }
/** true iff this quantity has no dimension **/
constexpr bool is_dimensionless() const { return unit_.is_dimensionless(); }
/** return abbreviation for quantities with this unit **/
constexpr nu_abbrev_type abbrev() const { return unit_.abbrev(); }
///@}
/** @defgroup xquantity-methods xquantity methods **/
///@{
/** create unit quantity with same unit as @c this **/
constexpr xquantity unit_qty() const { return xquantity(1, unit_); }
/** create zero quantity with same unit as @c this **/
constexpr xquantity zero_qty() const { return xquantity(0, unit_); }
/** create quantity representing reciprocal of @c this **/
constexpr xquantity reciprocal() const { return xquantity(1.0 / scale_, unit_.reciprocal()); }
/** create quantity representing the same value, but in units of @p unit2 **/
constexpr
auto rescale(const natural_unit<Int> & unit2) const {
/* conversion factor from .unit -> unit2*/
@ -86,24 +133,28 @@ namespace xo {
}
}
/** create quantity representing this value scaled by dimensionless mutliplier @p x **/
template <typename Dimensionless>
requires std::is_arithmetic_v<Dimensionless>
constexpr auto scale_by(Dimensionless x) const {
return xquantity(x * this->scale_, this->unit_);
}
/** create quantity representing this value scaled by dimensionless multiplier @p 1/x **/
template <typename Dimensionless>
requires std::is_arithmetic_v<Dimensionless>
constexpr auto divide_by(Dimensionless x) const {
return xquantity(this->scale_ / x, this->unit_);
}
/** create quantity representing dimensionless numerator @p x divided by this value **/
template <typename Dimensionless>
requires std::is_arithmetic_v<Dimensionless>
constexpr auto divide_into(Dimensionless x) const {
return xquantity(x / this->scale_, this->unit_.reciprocal());
}
/** multiply two @c xquantity values, or a mixed (@c xquantity, @c quantity) pair **/
template <typename Quantity2>
static constexpr
auto multiply(const xquantity & x, const Quantity2 & y) {
@ -125,6 +176,7 @@ namespace xo {
rr.natural_unit_);
}
/** compute quotient @p x / @p y, where @p x and @p y are xquantities **/
template <typename Quantity2>
static constexpr
auto divide(const xquantity & x, const Quantity2 & y) {
@ -149,6 +201,7 @@ namespace xo {
rr.natural_unit_);
}
/** compute sum @p x + @p y, where @p x and @p y are xquantities **/
template <typename Quantity2>
static constexpr
auto add(const xquantity & x, const Quantity2 & y) {
@ -176,6 +229,7 @@ namespace xo {
}
}
/** compute difference @p x - @p y, where @p x and @p y are xquantities **/
template <typename Quantity2>
static constexpr
auto subtract(const xquantity & x, const Quantity2 & y) {
@ -203,6 +257,7 @@ namespace xo {
}
}
/** perform 3-way comparison between @c xquantity values @p x and @p y **/
template <typename Quantity2>
static constexpr
auto compare(const xquantity & x, const Quantity2 & y) {
@ -211,6 +266,10 @@ namespace xo {
return x.scale() <=> y2.scale();
}
///@}
/** @defgroup xquantity-operators xquantity operators **/
///@{
xquantity operator-() const {
return xquantity(-scale_, unit_);
}
@ -228,16 +287,20 @@ namespace xo {
*this = *this / x;
return *this;
}
///@}
// TODO: operator+=, operator-=
constexpr nu_abbrev_type abbrev() const { return unit_.abbrev(); }
private:
/** @brief quantity represents this multiple of a unit amount **/
/** @defgroup xquantity-instance-vars **/
///@{
/** quantity represents this multiple of a unit amount **/
Repr scale_ = Repr{};
/** @brief unit for this quantity **/
/** unit for this quantity **/
natural_unit<Int> unit_;
///@}
}; /*xquantity*/
/** note: won't have constexpr result until c++26 (when ::sqrt(), ::pow() are constexpr)
@ -273,6 +336,26 @@ namespace xo {
return Q1::multiply(x, y);
}
/** note: won't have constexpr result until c++26 (when ::sqrt(), ::pow() are constexpr)
**/
template <typename Quantity>
requires quantity_concept<Quantity>
constexpr auto
operator* (double x, const Quantity & y)
{
return y.scale_by(x);
}
/** note: won't have constexpr result until c++26 (when ::sqrt(), ::pow() are constexpr)
**/
template <typename Quantity>
requires quantity_concept<Quantity>
constexpr auto
operator* (const Quantity & x, double y)
{
return x.scale_by(y);
}
/** note: won't have constexpr result until c++26 (when ::sqrt(), ::pow() are constexpr)
**/
template <typename Quantity, typename Quantity2>
@ -334,7 +417,8 @@ namespace xo {
/** note: won't have constexpr result until c++26 (when ::sqrt(), ::pow() are constexpr)
**/
template <typename Quantity, typename Quantity2>
requires quantity_concept<Quantity> && quantity_concept<Quantity2>
requires (quantity_concept<Quantity>
&& quantity_concept<Quantity2>)
constexpr auto
operator- (const Quantity & x, const Quantity2 & y)
{