From 86f87e352b95c3b4ab221f7d4e94118e84740d07 Mon Sep 17 00:00:00 2001
From: Alex Hamilton <alex.hamilton@ou.edu>
Date: Tue, 1 May 2018 19:47:32 -0500
Subject: [PATCH] Add electric charge quantity and associated units.

---
 src/si/electric_charge.rs | 97 +++++++++++++++++++++++++++++++++++++++
 src/si/mod.rs             |  1 +
 2 files changed, 98 insertions(+)
 create mode 100644 src/si/electric_charge.rs

diff --git a/src/si/electric_charge.rs b/src/si/electric_charge.rs
new file mode 100644
index 00000000..3ad2e576
--- /dev/null
+++ b/src/si/electric_charge.rs
@@ -0,0 +1,97 @@
+//! Electric charge (base unit coulomb, A · s).
+
+quantity! {
+    /// Electric charge (base unit coulomb, A · s).
+    quantity: ElectricCharge; "electric charge";
+    /// Electric charge dimension, A · s.
+    dimension: ISQ<
+        Z0,     // length
+        Z0,     // mass
+        P1,     // time
+        P1,     // electric current
+        Z0,     // thermodynamic temperature
+        Z0,     // amount of substance
+        Z0>;    // luminous intensity
+    units {
+        @yottacoulomb: prefix!(yotta); "YC", "yottacoulomb", "yottacoulombs";
+        @zettacoulomb: prefix!(zetta); "ZC", "zettacoulomb", "zettacoulombs";
+        @exacoulomb: prefix!(exa); "EC", "exacoulomb", "exacoulombs";
+        @petacoulomb: prefix!(peta); "PC", "petacoulomb", "petacoulombs";
+        @teracoulomb: prefix!(tera); "TC", "teracoulomb", "teracoulombs";
+        @gigacoulomb: prefix!(giga); "GC", "gigacoulomb", "gigacoulombs";
+        @megacoulomb: prefix!(mega); "MC", "megacoulomb", "megacoulombs";
+        @kilocoulomb: prefix!(kilo); "kC", "kilocoulomb", "kilocoulombs";
+        @hectocoulomb: prefix!(hecto); "hC", "hectocoulomb", "hectocoulombs";
+        @decacoulomb: prefix!(deca); "daC", "decacoulomb", "decacoulombs";
+        /// Derived unit of electric charge.
+        @coulomb: prefix!(none); "C", "coulomb", "coulombs";
+        @decicoulomb: prefix!(deci); "dC", "decicoulomb", "decicoulombs";
+        @centicoulomb: prefix!(centi); "cC", "centicoulomb", "centicoulombs";
+        @millicoulomb: prefix!(milli); "mC", "millcoulomb", "millcoulombs";
+        @microcoulomb: prefix!(micro); "µC", "microcoulomb", "microcoulombs";
+        @nanocoulomb: prefix!(nano); "nC", "nanocoulomb", "nanocoulombs";
+        @picocoulomb: prefix!(pico); "pC", "picocoulomb", "picocoulombs";
+        @femtocoulomb: prefix!(femto); "fC", "femtocoulomb", "femtocoulombs";
+        @attocoulomb: prefix!(atto); "aC", "attocoulomb", "attocoulombs";
+        @zeptocoulomb: prefix!(zepto); "zC", "zeptocoulomb", "zeptocoulombs";
+        @yoctocoulomb: prefix!(yocto); "yC", "yoctocoulomb", "yoctocoulombs";
+
+        @abcoulomb: 1.0_E1; "abC", "abcoulomb", "abcoulombs";
+        @ampere_hour: 3.6_E3; "A · h", "ampere hour", "ampere hours";
+        @faraday: 9.648_531_E4; "F", "faraday", "faradays";
+        @franklin: 3.335_641_E-10; "Fr", "franklin", "franklins";
+        @statcoulomb: 3.335_641_E-10; "statC", "statcoulomb", "statcoulombs";
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    storage_types! {
+        use num::One;
+        use si::quantities::*;
+        use si::time as t;
+        use si::electric_current as i;
+        use si::electric_charge as q;
+        use tests::Test;
+
+        #[test]
+        fn check_dimension() {
+            let _: ElectricCharge<V> = ElectricCurrent::new::<i::ampere>(V::one())
+                * Time::new::<t::second>(V::one());
+        }
+
+        #[test]
+        fn check_units() {
+            test::<i::yottaampere, t::second, q::yottacoulomb>();
+            test::<i::zettaampere, t::second, q::zettacoulomb>();
+            test::<i::exaampere, t::second, q::exacoulomb>();
+            test::<i::petaampere, t::second, q::petacoulomb>();
+            test::<i::teraampere, t::second, q::teracoulomb>();
+            test::<i::gigaampere, t::second, q::gigacoulomb>();
+            test::<i::megaampere, t::second, q::megacoulomb>();
+            test::<i::kiloampere, t::second, q::kilocoulomb>();
+            test::<i::hectoampere, t::second, q::hectocoulomb>();
+            test::<i::decaampere, t::second, q::decacoulomb>();
+            test::<i::ampere, t::second, q::coulomb>();
+            test::<i::deciampere, t::second, q::decicoulomb>();
+            test::<i::centiampere, t::second, q::centicoulomb>();
+            test::<i::milliampere, t::second, q::millicoulomb>();
+            test::<i::microampere, t::second, q::microcoulomb>();
+            test::<i::nanoampere, t::second, q::nanocoulomb>();
+            test::<i::picoampere, t::second, q::picocoulomb>();
+            test::<i::femtoampere, t::second, q::femtocoulomb>();
+            test::<i::attoampere, t::second, q::attocoulomb>();
+            test::<i::zeptoampere, t::second, q::zeptocoulomb>();
+            test::<i::yoctoampere, t::second, q::yoctocoulomb>();
+
+            test::<i::ampere, t::hour, q::ampere_hour>();
+            test::<i::abampere, t::second, q::abcoulomb>();
+            test::<i::statampere, t::second, q::statcoulomb>();
+
+            fn test<I: i::Conversion<V>, T: t::Conversion<V>, Q: q::Conversion<V>>() {
+                Test::assert_approx_eq(&ElectricCharge::new::<Q>(V::one()),
+                    &(ElectricCurrent::new::<I>(V::one()) * Time::new::<T>(V::one())));
+            }
+        }
+    }
+}
diff --git a/src/si/mod.rs b/src/si/mod.rs
index b8237ad9..2776a4dc 100644
--- a/src/si/mod.rs
+++ b/src/si/mod.rs
@@ -29,6 +29,7 @@ system! {
         density::Density,
         electrical_resistance::ElectricalResistance,
         electrical_conductance::ElectricalConductance,
+        electric_charge::ElectricCharge,
         electric_current::ElectricCurrent,
         electric_potential::ElectricPotential,
         energy::Energy,