Merge pull request eugenp#7995 from rodrigolgraciano/BAEL-2943

BAEL-2943

java-numbers/src/main/java/com/baeldung/nth/root/calculator/NthRootCalculator.java

@@ -1,8 +1,12 @@
 package com.baeldung.nth.root.calculator;
 
-public class NthRootCalculator
-{
-    public Double calculate(Double base, Double n) {
-        return Math.pow(Math.E, Math.log(base)/n);
+public class NthRootCalculator {
+
+    public double calculateWithRound(double base, double n) {
+        return Math.round(calculate(base, n));
+    }
+
+    public double calculate(double base, double n) {
+        return Math.pow(base, 1.0 / n);
     }
 }

java-numbers/src/main/java/com/baeldung/nth/root/main/Main.java

@@ -7,7 +7,7 @@ public static void main(String[] args) {
         NthRootCalculator calculator = new NthRootCalculator();
         Double base = Double.parseDouble(args[0]);
         Double n = Double.parseDouble(args[1]);
-        Double result = calculator.calculate(base, n);
+        Double result = calculator.calculateWithRound(base, n);
         System.out.println("The " + n + " root of " + base + " equals to " + result + ".");
     }
 }

java-numbers/src/test/java/com/baeldung/nth/root/calculator/NthRootCalculatorUnitTest.java

@@ -1,19 +1,22 @@
 package com.baeldung.nth.root.calculator;
 
-import static org.junit.Assert.assertEquals;
-
 import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.InjectMocks;
-import org.mockito.junit.MockitoJUnitRunner;
+
+import static org.junit.Assert.assertEquals;
 
 public class NthRootCalculatorUnitTest {
 
     private NthRootCalculator nthRootCalculator = new NthRootCalculator();
 
     @Test
-    public void whenBaseIs125AndNIs3_thenNthRootIs5() {
-       Double result = nthRootCalculator.calculate(125.0, 3.0);
-       assertEquals(result, (Double) 5.0d);
+    public void whenBaseIs125AndNIs3_thenNthIs5() {
+        double nth = nthRootCalculator.calculateWithRound(125,3);
+        assertEquals(5, nth, 0);
+    }
+
+    @Test
+    public void whenBaseIs625AndNIs4_thenNthIs5() {
+        double nth = nthRootCalculator.calculate(625,4);
+        assertEquals(5, nth, 0.00001);
     }
 }