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feat: full-on dimensional analysis between related quantity kinds

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This commit is contained in:
Johel Ernesto Guerrero Peña
2021-02-21 00:17:03 +01:00
committed by Mateusz Pusz
parent dad9b4f166
commit 017183653d
11 changed files with 295 additions and 49 deletions
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docs/framework/dimensions.rst
+30 -13
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@@ -67,23 +67,40 @@ dimension, than we will end up with just a dimensionless quantity:
Quantity Kinds
++++++++++++++
Quantity kinds behave the same as quantities for addition and subtraction.
The same behavior is also provided for multiplication with, and division by
a :term:`scalable number`.
Multiplication and division with a quantity (but not a quantity kind) is allowed.
The result is a quantity kind with the appropriate dimension
and related to the original quantity kind:
Quantity kinds behave the same as quantities for all operations,
except that the quantity types in the operators' declarations
are quantity kind types instead.
Additionally, for the dimensional analysis operators,
you can use a quantity argument instead of a quantity kind.
.. code-block::
:emphasize-lines: 5-6
:emphasize-lines: 8-9
struct height : kind<height, dim_length> {};
struct rate_of_climb : derived_kind<rate_of_climb, height, dim_speed> {};
struct height_kind : kind<height_kind, dim_length> {};
struct rate_of_climb_kind : derived_kind<rate_of_climb_kind, height_kind, dim_speed> {};
quantity_kind h(height{}, 100 * m);
quantity_point_kind rate = h / (25 * s);
// quantity_point_kind<rate_of_climb, si::metre_per_second, int>(4 * m / s)
template <Unit U, QuantityValue Rep = double> using height = quantity_kind<height_kind, U, Rep>;
template <Unit U, QuantityValue Rep = double> using rate_of_climb = quantity_kind<rate_of_climb_kind, U, Rep>;
height h{100 * m};
rate_of_climb rate = h / (25 * s);
// quantity_kind<rate_of_climb_kind, si::metre_per_second, int>(4 * m / s)
.. code-block::
:emphasize-lines: 8-12
struct width_kind : kind<width_kind, dim_length> {};
struct horizontal_area_kind : derived_kind<horizontal_area_kind, width_kind, dim_area> {};
template <Unit U, QuantityValue Rep = double> using width = quantity_kind<width_kind, U, Rep>;
template <Unit U, QuantityValue Rep = double> using horizontal_area = quantity_kind<horizontal_area_kind, U, Rep>;
width w{5 * m};
horizontal_area area1 = w * w;
// quantity_kind<horizontal_area_kind, si::metre_per_second, int>(25 * m * m)
width w2 = area1 / w; // quantity_kind<width_kind, si::metre, int>(5 * m)
auto q1 = w / w; // Dimensionless quantity kinds related to width
auto q2 = w / (5 * m); // with .common() equal to quantity{1}
Quantity Points
+++++++++++++++
docs/framework/quantity_kinds.rst
+2 -2
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@@ -41,7 +41,7 @@ the value to the `quantity_kind` class template constructor::
Differences To Quantity
-----------------------
Unlike `quantity`, the library provides:
The library provides:
- no kinds, such as ``radius`` or ``width``, therefore
@@ -49,7 +49,7 @@ Unlike `quantity`, the library provides:
* no kind-specific concepts, such as ``Radius``,
(there's the generic `QuantityKind` and kind-specifiable `QuantityKindOf`),
- a slightly different set of operations on quantity kinds
- a slightly larger set of operations on quantity kinds
(see the :ref:`framework/dimensions:Quantity Kinds` chapter).