forked from mpusz/mp-units
52 lines
1.6 KiB
ReStructuredText
52 lines
1.6 KiB
ReStructuredText
.. namespace:: units
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Quantity-like Types
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===================
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.. raw:: html
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<object data="../_images/quantity_like.svg" type="image/svg+xml" class="align-center" style="max-width: 100%;"></object>
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..
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https://www.planttext.com
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@startuml
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skinparam monochrome true
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skinparam shadowing false
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skinparam backgroundColor #fcfcfc
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hide members
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hide circle
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class quantity [[../framework/quantities.html]]
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class quantity_point [[../framework/quantity_points.html]]
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class quantity_kind [[../framework/quantity_kinds.html]]
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class quantity_point_kind [[../framework/quantity_kinds.html#quantity-point-kinds]]
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Rep <-- quantity : number()
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quantity <-- quantity_point : relative()
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quantity <-- quantity_kind : common()
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quantity_kind <-- quantity_point_kind : relative()
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@enduml
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[ISO80000]_ defines a :term:`quantity` as a:
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Property of a phenomenon, body, or substance, where the property has a magnitude that can be expressed by
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means of a number and a reference.
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You can use `quantity::number()` member function to get a concrete amount of a unit expressed with a specific
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representation type ``Rep``.
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:term:`Kind of quantity <kind of quantity>` is defined as:
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Aspect common to mutually comparable quantities.
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We can obtain a `quantity` with a `quantity_kind::common()` member function.
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`quantity_point` and `quantity_point_kind` are absolute quantities and quantity kinds relative to some
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specific origin. `quantity` and `quantity_point` types can be obtained from them using a ``relative()`` member
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function (`quantity_point::relative()`, `quantity_point_kind::relative()`).
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