241 lines
8.4 KiB
Rust

use super::{
BlockMatrix, DiagonalMatrix, Matrix, OperatorType, RowVector, SbpOperator1d, SbpOperator2d,
UpwindOperator1d, UpwindOperator2d,
};
use crate::Float;
use ndarray::{ArrayView1, ArrayView2, ArrayViewMut1, ArrayViewMut2};
#[derive(Debug, Copy, Clone)]
pub struct Upwind4;
impl Upwind4 {
#[rustfmt::skip]
const H: DiagonalMatrix<4> = DiagonalMatrix::new([
49.0 / 144.0, 61.0 / 48.0, 41.0 / 48.0, 149.0 / 144.0
]);
#[rustfmt::skip]
const MINIMAL_DIFF_BLOCK: Matrix<Float, 4, 7> = Matrix::new([
[ -72.0 / 49.0, 187.0 / 98.0, -20.0 / 49.0, -3.0 / 98.0, 0.0, 0.0, 0.0],
[-187.0 / 366.0, 0.0, 69.0 / 122.0, -16.0 / 183.0, 2.0 / 61.0, 0.0, 0.0],
[ 20.0 / 123.0, -69.0 / 82.0, 0.0, 227.0 / 246.0, -12.0 / 41.0, 2.0 / 41.0, 0.0],
[ 3.0 / 298.0, 16.0 / 149.0, -227.0 / 298.0, 0.0, 126.0 / 149.0, -36.0 / 149.0, 6.0 / 149.0],
]);
const DIFF_BLOCK: Matrix<Float, 4, 8> = Self::MINIMAL_DIFF_BLOCK.resize();
#[rustfmt::skip]
const DIFF_DIAG: RowVector<Float, 7> = RowVector::new([[
-1.0 / 24.0, 1.0 / 4.0, -7.0 / 8.0, 0.0, 7.0 / 8.0, -1.0 / 4.0, 1.0 / 24.0
]]);
const DIFF_BLOCKEND: Matrix<Float, 4, 8> = Self::DIFF_BLOCK.flip_lr().flip_ud().flip_sign();
const DIFF: BlockMatrix<Float, 4, 8, 7> =
BlockMatrix::new(Self::DIFF_BLOCK, Self::DIFF_DIAG, Self::DIFF_BLOCKEND);
#[rustfmt::skip]
const MINIMAL_DISS_BLOCK: Matrix<Float, 4, 7> = Matrix::new([
[-3.0 / 49.0, 9.0 / 49.0, -9.0 / 49.0, 3.0 / 49.0, 0.0, 0.0, 0.0],
[ 3.0 / 61.0, -11.0 / 61.0, 15.0 / 61.0, -9.0 / 61.0, 2.0 / 61.0, 0.0, 0.0],
[-3.0 / 41.0, 15.0 / 41.0, -29.0 / 41.0, 27.0 / 41.0, -12.0 / 41.0, 2.0 / 41.0, 0.0],
[3.0 / 149.0, -27.0 / 149.0, 81.0 / 149.0, -117.0 / 149.0, 90.0 / 149.0, -36.0 / 149.0, 6.0 / 149.0],
]);
const DISS_BLOCK: Matrix<Float, 4, 8> = Self::MINIMAL_DISS_BLOCK.resize();
#[rustfmt::skip]
const DISS_DIAG: RowVector<Float, 7> = Matrix::new([[
1.0 / 24.0, -1.0 / 4.0, 5.0 / 8.0, -5.0 / 6.0, 5.0 / 8.0, -1.0 / 4.0, 1.0 / 24.0
]]);
const DISS_BLOCKEND: Matrix<Float, 4, 8> = Self::DISS_BLOCK.flip_lr().flip_ud();
const DISS: BlockMatrix<Float, 4, 8, 7> =
BlockMatrix::new(Self::DISS_BLOCK, Self::DISS_DIAG, Self::DISS_BLOCKEND);
}
impl SbpOperator1d for Upwind4 {
fn diff(&self, prev: ArrayView1<Float>, fut: ArrayViewMut1<Float>) {
super::diff_op_1d(&Self::DIFF, super::OperatorType::Normal, prev, fut)
}
fn h(&self) -> &'static [Float] {
&Self::H.start
}
#[cfg(feature = "sparse")]
fn diff_matrix(&self, n: usize) -> sprs::CsMat<Float> {
super::sparse_from_block(&Self::DIFF, super::OperatorType::Normal, n)
}
#[cfg(feature = "sparse")]
fn h_matrix(&self, n: usize) -> sprs::CsMat<Float> {
super::h_matrix(&Self::H, n, self.is_h2())
}
fn upwind(&self) -> Option<&dyn UpwindOperator1d> {
Some(&Self)
}
}
impl SbpOperator2d for Upwind4 {
fn diffxi(&self, prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>) {
assert_eq!(prev.shape(), fut.shape());
super::diff_op_2d(&Self::DIFF, OperatorType::Normal, prev, fut);
}
fn op_xi(&self) -> &dyn SbpOperator1d {
&Self
}
fn upwind(&self) -> Option<Box<dyn UpwindOperator2d>> {
Some(Box::new(Self))
}
}
#[test]
fn upwind4_test() {
use ndarray::prelude::*;
let nx = 20;
let dx = 1.0 / (nx - 1) as Float;
let mut source: ndarray::Array1<Float> = ndarray::Array1::zeros(nx);
let mut res = ndarray::Array1::zeros(nx);
let mut target = ndarray::Array1::zeros(nx);
for i in 0..nx {
source[i] = i as Float * dx;
target[i] = 1.0;
}
res.fill(0.0);
Upwind4.diff(source.view(), res.view_mut());
approx::assert_abs_diff_eq!(&res, &target, epsilon = 1e-4);
{
let source = source.to_owned().insert_axis(ndarray::Axis(0));
let mut res = res.to_owned().insert_axis(ndarray::Axis(0));
let target = target.to_owned().insert_axis(ndarray::Axis(0));
res.fill(0.0);
Upwind4.diffxi(source.view(), res.view_mut());
approx::assert_abs_diff_eq!(&res, &target, epsilon = 1e-2);
}
{
let source = Array2::from_shape_fn((nx, 8), |(i, _)| source[i]);
let target = Array2::from_shape_fn((nx, 8), |(i, _)| target[i]);
let mut res = Array2::zeros((nx, 8));
res.fill(0.0);
Upwind4.diffeta(source.view(), res.view_mut());
approx::assert_abs_diff_eq!(&res.to_owned(), &target.to_owned(), epsilon = 1e-2);
}
for i in 0..nx {
let x = i as Float * dx;
source[i] = x * x;
target[i] = 2.0 * x;
}
res.fill(0.0);
Upwind4.diff(source.view(), res.view_mut());
approx::assert_abs_diff_eq!(&res, &target, epsilon = 1e-4);
{
let source = source.to_owned().insert_axis(ndarray::Axis(0));
let mut res = res.to_owned().insert_axis(ndarray::Axis(0));
let target = target.to_owned().insert_axis(ndarray::Axis(0));
res.fill(0.0);
Upwind4.diffxi(source.view(), res.view_mut());
approx::assert_abs_diff_eq!(&res, &target, epsilon = 1e-2);
}
{
let source = Array2::from_shape_fn((nx, 8), |(i, _)| source[i]);
let target = Array2::from_shape_fn((nx, 8), |(i, _)| target[i]);
let mut res = Array2::zeros((nx, 8));
res.fill(0.0);
Upwind4.diffeta(source.view(), res.view_mut());
approx::assert_abs_diff_eq!(&res.to_owned(), &target.to_owned(), epsilon = 1e-2);
}
for i in 0..nx {
let x = i as Float * dx;
source[i] = x * x * x;
target[i] = 3.0 * x * x;
}
res.fill(0.0);
Upwind4.diff(source.view(), res.view_mut());
approx::assert_abs_diff_eq!(&res, &target, epsilon = 1e-2);
{
let source = source.to_owned().insert_axis(ndarray::Axis(0));
let mut res = res.to_owned().insert_axis(ndarray::Axis(0));
let target = target.to_owned().insert_axis(ndarray::Axis(0));
res.fill(0.0);
Upwind4.diffxi(source.view(), res.view_mut());
approx::assert_abs_diff_eq!(&res, &target, epsilon = 1e-2);
}
{
let source = Array2::from_shape_fn((nx, 8), |(i, _)| source[i]);
let target = Array2::from_shape_fn((nx, 8), |(i, _)| target[i]);
let mut res = Array2::zeros((nx, 8));
res.fill(0.0);
Upwind4.diffeta(source.view(), res.view_mut());
approx::assert_abs_diff_eq!(&res.to_owned(), &target.to_owned(), epsilon = 1e-2);
}
}
impl UpwindOperator1d for Upwind4 {
fn diss(&self, prev: ArrayView1<Float>, fut: ArrayViewMut1<Float>) {
super::diff_op_1d(&Self::DISS, super::OperatorType::Normal, prev, fut)
}
fn as_sbp(&self) -> &dyn SbpOperator1d {
self
}
#[cfg(feature = "sparse")]
fn diss_matrix(&self, n: usize) -> sprs::CsMat<Float> {
super::sparse_from_block(&Self::DISS, super::OperatorType::Normal, n)
}
}
impl UpwindOperator2d for Upwind4 {
fn dissxi(&self, prev: ArrayView2<Float>, fut: ArrayViewMut2<Float>) {
assert_eq!(prev.shape(), fut.shape());
super::diff_op_2d(&Self::DISS, OperatorType::Normal, prev, fut)
}
fn op_xi(&self) -> &dyn UpwindOperator1d {
&Self
}
}
#[test]
fn upwind4_test2() {
use super::testing::*;
use super::*;
let nx = 32;
let ny = 16;
check_operator_on(
Upwind4,
(ny, nx),
|x, y| x + 2.0 * y,
|_, _| 1.0,
|_, _| 2.0,
1e-4,
);
check_operator_on(
Upwind4,
(ny, nx),
|x, y| x * x + 2.0 * x * y + 3.0 * y * y,
|x, y| 2.0 * x + 2.0 * y,
|x, y| 2.0 * x + 6.0 * y,
1e-3,
);
check_operator_on(
Upwind4,
(ny, nx),
|x, y| x.powi(3) + 2.0 * x.powi(2) * y + 3.0 * x * y.powi(2) + 4.0 * y.powi(3),
|x, y| 3.0 * x.powi(2) + 4.0 * x * y + 3.0 * y.powi(2),
|x, y| 2.0 * x.powi(2) + 6.0 * x * y + 12.0 * y.powi(2),
1e-1,
);
check_operator_on(
Upwind4,
(32, 32),
|x, y| x.powi(3) + 2.0 * x.powi(2) * y + 3.0 * x * y.powi(2) + 4.0 * y.powi(3),
|x, y| 3.0 * x.powi(2) + 4.0 * x * y + 3.0 * y.powi(2),
|x, y| 2.0 * x.powi(2) + 6.0 * x * y + 12.0 * y.powi(2),
1e-1,
);
}