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clean up code, fudge approx true

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This commit is contained in:
miguel raz 2021-06-01 20:05:30 -05:00
parent 70305c5fad
commit c042f33673
1 changed files with 5 additions and 13 deletions
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18
crates/core_simd/examples/nbody.rs
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@ -14,7 +14,6 @@ pub struct Body {
pub mass: f64,
}
// translation up to here
const N_BODIES: usize = 5;
const BODIES: [Body; N_BODIES] = [
// sun:
@ -134,7 +133,6 @@ pub fn advance(bodies: &mut [Body; N_BODIES], dt: f64) {
(r[i + 1] * r[i + 1]).horizontal_sum(),
]);
let dmags = f64x2::splat(dt) / (d2s * d2s.sqrt());
// dmags.write_to_slice_unaligned(&mut mag[i..]);
mag[i] = dmags[0];
mag[i + 1] = dmags[1];
i += 2;
@ -154,12 +152,6 @@ pub fn advance(bodies: &mut [Body; N_BODIES], dt: f64) {
}
}
// #[inline]
// pub unsafe fn write_to_slice_unaligned(slice: &mut SimdF64::<LANES>) {
// let target_ptr = slice.get_unchecked_mut(0) as *mut f64x2;
// *(target_ptr as *mut f64x2) = SimdF64;
// }
pub fn run(n: usize) -> (f64, f64) {
let mut bodies = BODIES;
offset_momentum(&mut bodies);
@ -172,8 +164,9 @@ pub fn run(n: usize) -> (f64, f64) {
(energy_before, energy_after)
}
fn approx_eq_f32(a: f32, b: f32) -> bool {
(a - b).abs() < 0.00000001
// Good enough for demonstration purposes, not going for strictness here.
fn approx_eq_f64(a: f64, b: f64) -> bool {
(a - b).abs() < 0.00001
}
#[cfg(test)]
@ -183,9 +176,8 @@ mod tests {
use super::*;
const OUTPUT: [f64; 2] = [-0.169075164, -0.169087605];
let (energy_before, energy_after) = super::run(1000);
assert!(approx_eq_f32(energy_before as f32, OUTPUT[0] as f32));
assert!(approx_eq_f32(energy_after as f32, OUTPUT[1] as f32));
// }
assert!(approx_eq_f64(energy_before, OUTPUT[0]));
assert!(approx_eq_f64(energy_after, OUTPUT[1]));
}
}