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NTTP ratio support added (resolves #49)

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Mateusz Pusz
2020-06-27 19:15:46 +02:00
parent 03facbefd2
commit d171f5451e
47 changed files with 504 additions and 664 deletions
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docs/framework/units.rst
+35 -32
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@@ -186,20 +186,23 @@ Those units are the scaled versions of a time dimension's base unit,
namely second. Those can be defined easily in the library using
`named_scaled_unit` class template::
struct minute : named_scaled_unit<minute, "min", no_prefix, ratio<60>, second> {};
struct hour : named_scaled_unit<hour, "h", no_prefix, ratio<60>, minute> {};
struct day : named_scaled_unit<hour, "d", no_prefix, ratio<24>, hour> {};
struct minute : named_scaled_unit<minute, "min", no_prefix, ratio(60), second> {};
struct hour : named_scaled_unit<hour, "h", no_prefix, ratio(60), minute> {};
struct day : named_scaled_unit<hour, "d", no_prefix, ratio(24), hour> {};
where `no_prefix` is a special tag type describing that the library should
not allow to define a new prefixed unit that would use this unit as a
reference ("kilohours" does not have much sense, right?). The `ratio` type
used in the definition is really similar to ``std::ratio`` but it takes
the third additional argument that defines the exponent of the ratio.
an additional ``Exp`` template parameter that defines the exponent of the ratio.
Another important difference is the fact that the objects of that class are used
as class NTTPs rather then a type template parameter kind.
Thanks to it we can address nearly infinite scaling factors between units
and define units like::
struct electronvolt : named_scaled_unit<electronvolt, "eV", prefix,
ratio<1'602'176'634, 1'000'000'000, -19>, joule> {};
ratio(1'602'176'634, 1'000'000'000, -19), joule> {};
..
TODO Submit a bug for above lexing problem
@@ -221,26 +224,26 @@ complete list of all the :term:`SI` prefixes supported by the library::
struct prefix : prefix_family {};
struct yocto : units::prefix<yocto, prefix, "y", ratio<1, 1, -24>> {};
struct zepto : units::prefix<zepto, prefix, "z", ratio<1, 1, -21>> {};
struct atto : units::prefix<atto, prefix, "a", ratio<1, 1, -18>> {};
struct femto : units::prefix<femto, prefix, "f", ratio<1, 1, -15>> {};
struct pico : units::prefix<pico, prefix, "p", ratio<1, 1, -12>> {};
struct nano : units::prefix<nano, prefix, "n", ratio<1, 1, -9>> {};
struct micro : units::prefix<micro, prefix, "µ", ratio<1, 1, -6>> {};
struct milli : units::prefix<milli, prefix, "m", ratio<1, 1, -3>> {};
struct centi : units::prefix<centi, prefix, "c", ratio<1, 1, -2>> {};
struct deci : units::prefix<deci, prefix, "d", ratio<1, 1, -1>> {};
struct deca : units::prefix<deca, prefix, "da", ratio<1, 1, 1>> {};
struct hecto : units::prefix<hecto, prefix, "h", ratio<1, 1, 2>> {};
struct kilo : units::prefix<kilo, prefix, "k", ratio<1, 1, 3>> {};
struct mega : units::prefix<mega, prefix, "M", ratio<1, 1, 6>> {};
struct giga : units::prefix<giga, prefix, "G", ratio<1, 1, 9>> {};
struct tera : units::prefix<tera, prefix, "T", ratio<1, 1, 12>> {};
struct peta : units::prefix<peta, prefix, "P", ratio<1, 1, 15>> {};
struct exa : units::prefix<exa, prefix, "E", ratio<1, 1, 18>> {};
struct zetta : units::prefix<zetta, prefix, "Z", ratio<1, 1, 21>> {};
struct yotta : units::prefix<yotta, prefix, "Y", ratio<1, 1, 24>> {};
struct yocto : units::prefix<yocto, prefix, "y", ratio(1, 1, -24)> {};
struct zepto : units::prefix<zepto, prefix, "z", ratio(1, 1, -21)> {};
struct atto : units::prefix<atto, prefix, "a", ratio(1, 1, -18)> {};
struct femto : units::prefix<femto, prefix, "f", ratio(1, 1, -15)> {};
struct pico : units::prefix<pico, prefix, "p", ratio(1, 1, -12)> {};
struct nano : units::prefix<nano, prefix, "n", ratio(1, 1, -9)> {};
struct micro : units::prefix<micro, prefix, "µ", ratio(1, 1, -6)> {};
struct milli : units::prefix<milli, prefix, "m", ratio(1, 1, -3)> {};
struct centi : units::prefix<centi, prefix, "c", ratio(1, 1, -2)> {};
struct deci : units::prefix<deci, prefix, "d", ratio(1, 1, -1)> {};
struct deca : units::prefix<deca, prefix, "da", ratio(1, 1, 1)> {};
struct hecto : units::prefix<hecto, prefix, "h", ratio(1, 1, 2)> {};
struct kilo : units::prefix<kilo, prefix, "k", ratio(1, 1, 3)> {};
struct mega : units::prefix<mega, prefix, "M", ratio(1, 1, 6)> {};
struct giga : units::prefix<giga, prefix, "G", ratio(1, 1, 9)> {};
struct tera : units::prefix<tera, prefix, "T", ratio(1, 1, 12)> {};
struct peta : units::prefix<peta, prefix, "P", ratio(1, 1, 15)> {};
struct exa : units::prefix<exa, prefix, "E", ratio(1, 1, 18)> {};
struct zetta : units::prefix<zetta, prefix, "Z", ratio(1, 1, 21)> {};
struct yotta : units::prefix<yotta, prefix, "Y", ratio(1, 1, 24)> {};
}
@@ -251,12 +254,12 @@ domain::
struct prefix : prefix_family {};
struct kibi : units::prefix<kibi, prefix, "Ki", ratio< 1'024>> {};
struct mebi : units::prefix<mebi, prefix, "Mi", ratio< 1'048'576>> {};
struct gibi : units::prefix<gibi, prefix, "Gi", ratio< 1'073'741'824>> {};
struct tebi : units::prefix<tebi, prefix, "Ti", ratio< 1'099'511'627'776>> {};
struct pebi : units::prefix<pebi, prefix, "Pi", ratio< 1'125'899'906'842'624>> {};
struct exbi : units::prefix<exbi, prefix, "Ei", ratio<1'152'921'504'606'846'976>> {};
struct kibi : units::prefix<kibi, prefix, "Ki", ratio( 1'024)> {};
struct mebi : units::prefix<mebi, prefix, "Mi", ratio( 1'048'576)> {};
struct gibi : units::prefix<gibi, prefix, "Gi", ratio( 1'073'741'824)> {};
struct tebi : units::prefix<tebi, prefix, "Ti", ratio( 1'099'511'627'776)> {};
struct pebi : units::prefix<pebi, prefix, "Pi", ratio( 1'125'899'906'842'624)> {};
struct exbi : units::prefix<exbi, prefix, "Ei", ratio(1'152'921'504'606'846'976)> {};
}
@@ -381,7 +384,7 @@ unknown/undefined unit type like in the below example::
Length auto l = 100q_km_per_h * 10q_s;
The type of ``l`` above will be
:expr:`si::length<scaled_unit<ratio<1, 36, 1>, si::metre>, long double>`. This is caused
:expr:`si::length<scaled_unit<ratio(1, 36, 1), si::metre>, long double>`. This is caused
by the fact that the library does not define a unit of a length quantity that has the
ratio ``10/36`` of a `si::metre`. If such a unit was predefined we would see its concrete
type here instead.