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use super::measurement::*;
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
#[derive(Copy, Clone, Debug)]
pub struct Energy {
joules: f64,
}
impl Energy {
pub fn from_joules(joules: f64) -> Energy {
Energy { joules: joules }
}
pub fn from_kcalories(kcalories: f64) -> Energy {
Self::from_joules(kcalories * 4186.8)
}
pub fn from_btu(btu: f64) -> Energy {
Self::from_joules(btu * 1055.056)
}
pub fn from_e_v(e_v: f64) -> Energy {
Self::from_joules(e_v / 6.241509479607718e+18)
}
pub fn from_watt_hours(wh: f64) -> Energy {
Self::from_joules(wh * 3600.0)
}
pub fn from_kilowatt_hours(kwh: f64) -> Energy {
Self::from_joules(kwh * 3600.0 * 1000.0)
}
pub fn as_joules(&self) -> f64 {
self.joules
}
pub fn as_kcalories(&self) -> f64 {
self.joules / 4186.8
}
pub fn as_btu(&self) -> f64 {
self.joules / 1055.056
}
pub fn as_e_v(&self) -> f64 {
self.joules * 6.241509479607718e+18
}
pub fn as_watt_hours(&self) -> f64 {
self.joules / 3600.0
}
pub fn as_kilowatt_hours(&self) -> f64 {
self.joules / (3600.0 * 1000.0)
}
}
impl Measurement for Energy {
fn as_base_units(&self) -> f64 {
self.joules
}
fn from_base_units(units: f64) -> Self {
Self::from_joules(units)
}
fn get_base_units_name(&self) -> &'static str {
"J"
}
fn get_appropriate_units(&self) -> (&'static str, f64) {
let list = [
("fJ", 1e-15),
("pJ", 1e-12),
("nJ", 1e-9),
("\u{00B5}J", 1e-6),
("mJ", 1e-3),
("J", 1e0),
("kJ", 1e3),
("MJ", 1e6),
("GJ", 1e9),
("TJ", 1e12),
("PJ", 1e15),
("EJ", 1e18),
];
self.pick_appropriate_units(&list)
}
}
implement_measurement! { Energy }
#[cfg(test)]
mod test {
use energy::*;
use test_utils::assert_almost_eq;
#[test]
pub fn as_kcalories() {
let i1 = Energy::from_kcalories(100.0);
let r1 = i1.as_joules();
let i2 = Energy::from_joules(100.0);
let r2 = i2.as_kcalories();
assert_almost_eq(r1, 418680.0);
assert_almost_eq(r2, 0.0238845896627496);
}
#[test]
pub fn as_btu() {
let i1 = Energy::from_btu(100.0);
let r1 = i1.as_joules();
let i2 = Energy::from_joules(100.0);
let r2 = i2.as_btu();
assert_almost_eq(r1, 105505.6);
assert_almost_eq(r2, 0.0947816987913438);
}
#[test]
pub fn as_e_v() {
let i1 = Energy::from_e_v(100.0);
let r1 = i1.as_joules();
let i2 = Energy::from_joules(100.0);
let r2 = i2.as_e_v();
assert_almost_eq(r1, 1.60217653e-17);
assert_almost_eq(r2, 6.241509479607718e+20);
}
#[test]
pub fn as_watt_hours() {
let i1 = Energy::from_watt_hours(100.0);
let r1 = i1.as_joules();
let i2 = Energy::from_joules(100.0);
let r2 = i2.as_watt_hours();
assert_almost_eq(r1, 360000.0);
assert_almost_eq(r2, 0.02777777777777777777777777777778);
}
#[test]
pub fn as_kilowatt_hours() {
let i1 = Energy::from_kilowatt_hours(100.0);
let r1 = i1.as_joules();
let i2 = Energy::from_joules(100.0);
let r2 = i2.as_kilowatt_hours();
assert_almost_eq(r1, 360000000.0);
assert_almost_eq(r2, 2.777777777777777777777777777778e-5);
}
#[test]
fn add() {
let a = Energy::from_joules(2.0);
let b = Energy::from_joules(4.0);
let c = a + b;
let d = b + a;
assert_almost_eq(c.as_joules(), 6.0);
assert_eq!(c, d);
}
#[test]
fn sub() {
let a = Energy::from_joules(2.0);
let b = Energy::from_joules(4.0);
let c = a - b;
assert_almost_eq(c.as_joules(), -2.0);
}
#[test]
fn mul() {
let a = Energy::from_joules(3.0);
let b = a * 2.0;
let c = 2.0 * a;
assert_almost_eq(b.as_joules(), 6.0);
assert_eq!(b, c);
}
#[test]
fn div() {
let a = Energy::from_joules(2.0);
let b = Energy::from_joules(4.0);
let c = a / b;
let d = a / 2.0;
assert_almost_eq(c, 0.5);
assert_almost_eq(d.as_joules(), 1.0);
}
#[test]
fn eq() {
let a = Energy::from_joules(2.0);
let b = Energy::from_joules(2.0);
assert_eq!(a == b, true);
}
#[test]
fn neq() {
let a = Energy::from_joules(2.0);
let b = Energy::from_joules(4.0);
assert_eq!(a == b, false);
}
#[test]
fn cmp() {
let a = Energy::from_joules(2.0);
let b = Energy::from_joules(4.0);
assert_eq!(a < b, true);
assert_eq!(a <= b, true);
assert_eq!(a > b, false);
assert_eq!(a >= b, false);
}
}