Add helper methods to reduce boilerplate code amount

andrei-punko · Oct 22, 2024 · 66400fe · 66400fe
1 parent 4707405
commit 66400fe
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Showing 7 changed files with 64 additions and 10 deletions.
diff --git a/src/main/java/by/andd3dfx/math/Area.java b/src/main/java/by/andd3dfx/math/Area.java
@@ -2,4 +2,19 @@
 
 public record Area(Interval x, Interval t) {
 
+    public double tLeft() {
+        return t().left();
+    }
+
+    public double tRight() {
+        return t().right();
+    }
+
+    public double xLeft() {
+        return x().left();
+    }
+
+    public double xRight() {
+        return x().right();
+    }
 }
diff --git a/src/main/java/by/andd3dfx/math/Matrix.java b/src/main/java/by/andd3dfx/math/Matrix.java
@@ -58,6 +58,10 @@ public void set(int i, int j, double value) {
         data[i * n + j] = value;
     }
 
+    public void set(int i, double[] arr) {
+        System.arraycopy(arr, 0, data, i * n, arr.length);
+    }
+
     public double get(int i, int j) {
         assert (i >= 0 && i < m && j >= 0 && j < n);
         return data[i * n + j];

diff --git a/src/main/java/by/andd3dfx/math/pde/equation/Equation.java b/src/main/java/by/andd3dfx/math/pde/equation/Equation.java
@@ -108,7 +108,7 @@ public void sUt(String fileName, double t) {
      */
     public void sUt(String fileName, double[] t) {
         for (var t_i : t) {
-            assert (area.t().left() <= t_i && t_i <= area.t().right());
+            assert (area.tLeft() <= t_i && t_i <= area.tRight());
         }
 
         var sb = new StringBuilder();
@@ -140,7 +140,7 @@ public void sUx(String fileName, double x) {
      */
     public void sUx(String fileName, double[] x) {
         for (var x_i : x) {
-            assert (area.x().left() <= x_i && x_i <= area.x().right());
+            assert (area.xLeft() <= x_i && x_i <= area.xRight());
         }
 
         var sb = new StringBuilder();

diff --git a/src/main/java/by/andd3dfx/math/pde/equation/HyperbolicEquation.java b/src/main/java/by/andd3dfx/math/pde/equation/HyperbolicEquation.java
@@ -51,8 +51,8 @@ public void solve(double h, double tau) {
                 _2h2_tau2 = 2 * Math.pow(h / tau, 2);
 
         // Set border conditions on layer 1
-        arr.set(1, 0, calcFirstLayerValue(tau, arr.get(0, 0), area.x().left()));
-        arr.set(1, N, calcFirstLayerValue(tau, arr.get(0, N), area.x().right()));
+        arr.set(1, 0, calcFirstLayerValue(tau, arr.get(0, 0), area.xLeft()));
+        arr.set(1, N, calcFirstLayerValue(tau, arr.get(0, N), area.xRight()));
 
         // Calculate U value on layer 1 which needed to start finite-difference algorithm
         //
@@ -118,9 +118,7 @@ public void solve(double h, double tau) {
             }
 
             progonka(A, B, C, F, Mu[1], Nu[1], Mu[2], Nu[2], U);
-            for (int i = 0; i <= N; i++) {
-                arr.set(nj, i, U[i]);
-            }
+            arr.set(nj, U);
         }
     }
 

diff --git a/src/main/java/by/andd3dfx/math/pde/equation/ParabolicEquation.java b/src/main/java/by/andd3dfx/math/pde/equation/ParabolicEquation.java
@@ -98,9 +98,7 @@ public void solve(double h, double tau) {
             }
 
             progonka(A, B, C, F, Mu[1], Nu[1], Mu[2], Nu[2], U);
-            for (int i = 0; i <= N; i++) {
-                arr.set(nj, i, U[i]);
-            }
+            arr.set(nj, U);
         }
     }
 }
diff --git a/src/test/java/by/andd3dfx/math/AreaTest.java b/src/test/java/by/andd3dfx/math/AreaTest.java
@@ -0,0 +1,18 @@
+package by.andd3dfx.math;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class AreaTest {
+
+    @Test
+    void xLeftRightNTLeftRight() {
+        var area = new Area(new Interval(3, 8, 10), new Interval(0, 10, 10));
+
+        assertThat(area.xLeft()).isEqualTo(3);
+        assertThat(area.xRight()).isEqualTo(8);
+        assertThat(area.tLeft()).isEqualTo(0);
+        assertThat(area.tRight()).isEqualTo(10);
+    }
+}
diff --git a/src/test/java/by/andd3dfx/math/MatrixTest.java b/src/test/java/by/andd3dfx/math/MatrixTest.java
@@ -158,4 +158,25 @@ void fill() {
         }
         assertThat(result).isEqualTo(m);
     }
+
+    @Test
+    void copyArrayIntoDefinitePositionOfData() {
+        var m = new Matrix(2, 4);
+        m.fill(3);
+        m.set(0, 0, 5);
+        m.set(0, 2, -5);
+        m.set(1, 0, 9);
+        m.set(1, 3, 1);
+
+        m.set(1, new double[]{9, 8, 7, 6});
+
+        assertThat(m.get(0, 0)).isEqualTo(5);
+        assertThat(m.get(0, 1)).isEqualTo(3);
+        assertThat(m.get(0, 2)).isEqualTo(-5);
+        assertThat(m.get(0, 3)).isEqualTo(3);
+        assertThat(m.get(1, 0)).isEqualTo(9);
+        assertThat(m.get(1, 1)).isEqualTo(8);
+        assertThat(m.get(1, 2)).isEqualTo(7);
+        assertThat(m.get(1, 3)).isEqualTo(6);
+    }
 }