From f34282811d7e6eae1b1e587d35700b20463bb9b5 Mon Sep 17 00:00:00 2001 From: Mateusz Pusz Date: Sat, 3 Sep 2022 12:28:21 +0200 Subject: [PATCH] docs: angular quantities documentation improved --- docs/framework/angular_units.rst | 13 ++++++++++++- docs/reference/systems/generic.rst | 1 + docs/reference/systems/generic/angle.rst | 5 +++++ docs/reference/systems/generic/solid_angle.rst | 8 ++++++++ docs/references.rst | 1 + 5 files changed, 27 insertions(+), 1 deletion(-) create mode 100644 docs/reference/systems/generic/solid_angle.rst diff --git a/docs/framework/angular_units.rst b/docs/framework/angular_units.rst index fca4bbdd..7f173bc6 100644 --- a/docs/framework/angular_units.rst +++ b/docs/framework/angular_units.rst @@ -26,7 +26,7 @@ as early as 1936 and as recently as 2022. This would bring the advantages of a p unit system, with unambiguous units for all physical quantities. At the same time the only notable changes for typical end-users would be: improved units for the quantities **torque**, **angular momentum** and **moment of inertia**. -Paul Quincey in his proposal `"Angles in the SI: a detailed proposal for solving the problem" `_ states: +Paul Quincey in his proposal *"Angles in the SI: a detailed proposal for solving the problem"* [Quincey]_ states: The familiar units assigned to some angular quantities are based on equations that have adopted the radian convention, and so are missing `rad`s that would be present if the complete equation is used. The physically-correct units are @@ -47,6 +47,17 @@ He proposes the following changes: **angular acceleration**, and **angular wavenumber** would be removed, the only correct SI units being :math:`rad`, :math:`rad/s`, :math:`rad/s`, :math:`rad/s^2` and :math:`rad/m` respectively. +Paul Quincey summarizes that with the above in action: + + However, the physical clarity this would build into the SI should be recognised very quickly. The units would tell us that + :math:`torque \times angle = energy`, and :math:`angular\:momentum \times angle = action`, for example, in the same way that they do for + :math:`force \times distance = energy`, :math:`linear\:momentum \times distance = action`, and + :math:`radiant\:intensity \times solid\:angle = radiant\:flux`. + Dimensional analysis could be used to its full extent. Software involving angular quantities would be rationalised. + Arguments about the correct units for frequency and angular frequency, and the meaning of the unit Hz, could be left behind. + The explanation of these changes would be considerably easier and more rewarding than explaining how a kilogram-sized mass + can be measured in terms of the Planck constant. + Angular quantities in the library --------------------------------- diff --git a/docs/reference/systems/generic.rst b/docs/reference/systems/generic.rst index 1759a546..10c2574c 100644 --- a/docs/reference/systems/generic.rst +++ b/docs/reference/systems/generic.rst @@ -7,3 +7,4 @@ Generic generic/unknown generic/dimensionless generic/angle + generic/solid_angle diff --git a/docs/reference/systems/generic/angle.rst b/docs/reference/systems/generic/angle.rst index bf6eeab0..bce4e508 100644 --- a/docs/reference/systems/generic/angle.rst +++ b/docs/reference/systems/generic/angle.rst @@ -2,7 +2,12 @@ Angle ===== .. doxygenstruct:: units::radian +.. doxygenstruct:: units::rotation +.. doxygenstruct:: units::degree +.. doxygenstruct:: units::gradian .. doxygenstruct:: units::dim_angle .. doxygentypedef:: units::angle + +.. doxygenvariable:: cotes_angle diff --git a/docs/reference/systems/generic/solid_angle.rst b/docs/reference/systems/generic/solid_angle.rst new file mode 100644 index 00000000..704afeab --- /dev/null +++ b/docs/reference/systems/generic/solid_angle.rst @@ -0,0 +1,8 @@ +Solid Angle +=========== + +.. doxygenstruct:: units::steradian + +.. doxygenstruct:: units::dim_solid_angle + +.. doxygentypedef:: units::solid_angle diff --git a/docs/references.rst b/docs/references.rst index 35181006..71220b98 100644 --- a/docs/references.rst +++ b/docs/references.rst @@ -2,3 +2,4 @@ References ========== .. [ISO80000] `ISO 80000-1:2009(E) "Quantities and units — Part 1: General" `_, International Organization for Standardization. +.. [Quincey] `"Angles in the SI: a detailed proposal for solving the problem" `_, Quincey, Paul (1 October 2021)