Нет решений (корней)

levelp · May 23, 2015 · 484d1ef · 484d1ef
1 parent 14bff05
commit 484d1ef
Show file tree

Hide file tree

Showing 2 changed files with 10 additions and 0 deletions.
diff --git a/src/main/java/QuadraticEquation.java b/src/main/java/QuadraticEquation.java
@@ -17,6 +17,8 @@ public static double[] solve(double a, double b, double c) {
         double D = Math.pow(b, 2) - 4 * a * c;
         if (Math.abs(D) < EPS)
             return new double[]{-b / (2 * a)};
+        if (D < 0)
+            return new double[]{};
         double d = Math.sqrt(D);
         return new double[]{(-b - d) / (2 * a), (-b + d) / (2 * a)};
     }

diff --git a/src/test/java/QuadraticEquationTest.java b/src/test/java/QuadraticEquationTest.java
@@ -35,4 +35,12 @@ public void testOneRootAccuracy() {
             assertArrayEquals("t(x-q)^2 = t*x^2 - 2*t*q*x + t*q^2", new double[]{q}, QuadraticEquation.solve(t, -2 * t * q, t * q * q), EPS);
         }
     }
+
+    /**
+     * Нет решений (корней)
+     */
+    @Test
+    public void testNoRoots() {
+        assertArrayEquals("x^2 + 2 = 0", new double[]{}, QuadraticEquation.solve(1, 0, 2), EPS);
+    }
 }