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docs: outdated affine space chapter updated

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Mateusz Pusz
2023-12-01 11:32:44 +01:00
parent b6b5832c56
commit 5121eca121
1 changed files with 8 additions and 13 deletions
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docs/users_guide/framework_basics/the_affine_space.md
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@@ -110,11 +110,11 @@ quantity_point qp5{-42 * m, mean_sea_level};
``` ```
The provided `quantity` representing an offset from the origin is stored inside the `quantity_point` The provided `quantity` representing an offset from the origin is stored inside the `quantity_point`
class template and can be obtained with a `quantity_from_origin()` member function: class template and can be obtained with a `quantity_from(PointOrigin)` member function:
```cpp ```cpp
constexpr quantity_point everest_base_camp_alt = mean_sea_level + isq::altitude(5364 * m); constexpr quantity_point everest_base_camp_alt = mean_sea_level + isq::altitude(5364 * m);
static_assert(everest_base_camp_alt.quantity_from_origin() == 5364 * m); static_assert(everest_base_camp_alt.quantity_from(mean_sea_level) == 5364 * m);
``` ```
@@ -137,17 +137,12 @@ The above can be used as an origin for subsequent _points_:
```cpp ```cpp
constexpr quantity_point first_climb_alt = everest_base_camp + isq::altitude(std::uint8_t{42} * m); constexpr quantity_point first_climb_alt = everest_base_camp + isq::altitude(std::uint8_t{42} * m);
static_assert(first_climb_alt.quantity_from_origin() == 42 * m); static_assert(first_climb_alt.quantity_from(everest_base_camp) == 42 * m);
static_assert(first_climb_alt.quantity_from(mean_sea_level) == 5406 * m);
``` ```
As we can see above, the `quantity_from_origin()` member function returns a relative distance from As we can see above, the `quantity_from()` member function returns a relative distance from the
the current point origin. In case we would like to know the absolute altitude that we reached on this climb, provided point origin.
we can subtract the absolute point origin from the current _point_:
```cpp
static_assert(first_climb_alt - mean_sea_level == 5406 * m);
static_assert(first_climb_alt - first_climb_alt.absolute_point_origin == 5406 * m);
```
### Converting between different representations of the same _point_ ### Converting between different representations of the same _point_
@@ -162,14 +157,14 @@ For this purpose, we can either use:
```cpp ```cpp
constexpr quantity_point<isq::altitude[m], mean_sea_level, int> qp = first_climb_alt; constexpr quantity_point<isq::altitude[m], mean_sea_level, int> qp = first_climb_alt;
static_assert(qp.quantity_from_origin() == 5406 * m); static_assert(qp.quantity_ref_from(qp.point_origin) == 5406 * m);
``` ```
- a dedicated conversion interface: - a dedicated conversion interface:
```cpp ```cpp
constexpr quantity_point qp = first_climb_alt.point_for(mean_sea_level); constexpr quantity_point qp = first_climb_alt.point_for(mean_sea_level);
static_assert(qp.quantity_from_origin() == 5406 * m); static_assert(qp.quantity_ref_from(qp.point_origin) == 5406 * m);
``` ```
!!! note !!! note