split euler and maxwell to separate crates

euler/tests/convergence.rs

@@ -0,0 +1,83 @@
+#![cfg(feature = "expensive_tests")]
+use euler::*;
+use ndarray::prelude::*;
+use sbp::Float;
+
+fn run_with_size(size: usize, op: impl sbp::operators::UpwindOperator2d + Copy) -> Float {
+    let nx = size;
+    let ny = size;
+    let x = Array1::linspace(-5.0, 5.0, nx);
+    let y = Array1::linspace(-5.0, 5.0, ny);
+
+    let x = x.broadcast((ny, nx)).unwrap().to_owned();
+    let y = y
+        .reversed_axes()
+        .broadcast((nx, ny))
+        .unwrap()
+        .reversed_axes()
+        .to_owned();
+
+    let vortex_params = VortexParameters {
+        vortices: {
+            let mut v = ArrayVec::new();
+            v.push(Vortice {
+                x0: -1.0,
+                y0: 0.0,
+                rstar: 0.5,
+                eps: 1.0,
+            });
+            v
+        },
+        mach: 0.5,
+    };
+
+    let mut sys = System::new(x, y, op);
+    sys.vortex(0.0, vortex_params.clone());
+
+    let time = 0.2;
+    let dt = 0.2 * Float::min(1.0 / (nx - 1) as Float, 1.0 / (ny - 1) as Float);
+
+    let nsteps = (time / dt) as usize;
+    for _ in 0..nsteps {
+        sys.advance_upwind(dt);
+    }
+
+    let mut verifield = Field::new(ny, nx);
+    verifield.vortex(sys.x(), sys.y(), nsteps as Float * dt, &vortex_params);
+
+    verifield.h2_err(sys.field(), &op)
+}
+
+fn convergence(op: impl sbp::operators::UpwindOperator2d + Copy) {
+    let sizes = [25, 35, 50, 71, 100, 150, 200];
+    let mut prev: Option<(usize, Float)> = None;
+    println!("Size\tError(h2)\tq");
+    for size in &sizes {
+        print!("{:3}x{:3}", size, size);
+        let e = run_with_size(*size, op);
+        print!("\t{:.10}", e);
+        if let Some(prev) = prev.take() {
+            let m0 = size * size;
+            let e0 = e;
+
+            let (size1, e1) = prev;
+            let m1 = size1 * size1;
+
+            let q =
+                Float::log10(e0 / e1) / Float::log10((m0 as Float / m1 as Float).powf(1.0 / 2.0));
+            print!("\t{}", q);
+        }
+        println!();
+        prev = Some((*size, e));
+    }
+}
+
+#[test]
+fn convergence_upwind4() {
+    convergence(sbp::operators::Upwind4);
+}
+
+#[test]
+fn convergence_upwind9() {
+    convergence(sbp::operators::Upwind9);
+}