Add first two functions

This commit is contained in:
Timothy Warren 2020-01-10 10:39:55 -05:00
parent 68191a488b
commit 3694480303

View File

@ -1,3 +1,134 @@
#![allow(
non_upper_case_globals,
non_camel_case_types,
non_snake_case,
)]
use std::mem;
use std::arch::x86_64::*;
use std::f64::consts::PI;
#[repr(C)]
struct body {
position: [f64; 3],
velocity: [f64; 3],
mass: f64,
}
const SOLAR_MASS: f64 = 4. * PI * PI;
const DAYS_PER_YEAR: f64 = 365.24;
const BODIES_COUNT: usize = 5;
static mut solar_Bodies: [body; BODIES_COUNT] = [
body { // Sun
mass: SOLAR_MASS,
position: [0.; 3],
velocity: [0.; 3],
},
body { // Jupiter
mass: 9.54791938424326609e-04 * SOLAR_MASS,
position: [
4.84143144246472090e+00,
-1.16032004402742839e+00,
-1.03622044471123109e-01
],
velocity: [
1.66007664274403694e-03 * DAYS_PER_YEAR,
7.69901118419740425e-03 * DAYS_PER_YEAR,
-6.90460016972063023e-05 * DAYS_PER_YEAR
]
},
body { // Saturn
mass: 2.85885980666130812e-04 * SOLAR_MASS,
position: [
8.34336671824457987e+00,
4.12479856412430479e+00,
-4.03523417114321381e-01
],
velocity: [
-2.76742510726862411e-03 * DAYS_PER_YEAR,
4.99852801234917238e-03 * DAYS_PER_YEAR,
2.30417297573763929e-05 * DAYS_PER_YEAR
]
},
body { // Uranus
mass: 4.36624404335156298e-05 * SOLAR_MASS,
position: [
1.28943695621391310e+01,
-1.51111514016986312e+01,
-2.23307578892655734e-01
],
velocity: [
2.96460137564761618e-03 * DAYS_PER_YEAR,
2.37847173959480950e-03 * DAYS_PER_YEAR,
-2.96589568540237556e-05 * DAYS_PER_YEAR
]
},
body { // Neptune
mass: 5.15138902046611451e-05 * SOLAR_MASS,
position: [
1.53796971148509165e+01,
-2.59193146099879641e+01,
1.79258772950371181e-01
],
velocity: [
2.68067772490389322e-03 * DAYS_PER_YEAR,
1.62824170038242295e-03 * DAYS_PER_YEAR,
-9.51592254519715870e-05 * DAYS_PER_YEAR
]
},
];
unsafe fn offset_Momentum(bodies: *mut body) {
for i in 0..BODIES_COUNT {
for m in 0..3 {
(*bodies.add(0)).velocity[m] -=
(*bodies.add(i)).velocity[m]
* (*bodies.add(i)).mass / SOLAR_MASS;
}
}
}
unsafe fn output_Energy(bodies: *mut body) {
let mut energy = 0.;
for i in 0..BODIES_COUNT {
// Add the kinetic energy for each body.
energy += 0.5 * (*bodies.add(i)).mass * (
(*bodies.add(i)).velocity[0]
* (*bodies.add(i)).velocity[0]
+ (*bodies.add(i)).velocity[1]
* (*bodies.add(i)).velocity[1]
+ (*bodies.add(i)).velocity[2]
* (*bodies.add(i)).velocity[2]);
// Add the potential energy between this body and
// every other body
for j in i+1..BODIES_COUNT {
let mut position_Delta =
[mem::MaybeUninit::<f64>::uninit(); 3];
for m in 0..3 {
position_Delta[m].as_mut_ptr().write(
(*bodies.add(i)).position[m]
- (*bodies.add(j)).position[m]
);
}
let position_Delta: [f64; 3] =
mem::transmute(position_Delta);
energy -= (*bodies.add(i)).mass
* (*bodies.add(j)).mass
/ f64::sqrt(
position_Delta[0]*position_Delta[0]+
position_Delta[1]*position_Delta[1]+
position_Delta[2]*position_Delta[2]
);
}
}
// Output the total energy of the system
println!("{:.9}", energy);
}
fn main() {
println!("Hello, world!");
}