refactor: RootPrecision

Author: alxkm

src/main/java/com/thealgorithms/others/RootPrecision.java

@@ -1,38 +1,21 @@
 package com.thealgorithms.others;
 
-import java.util.Scanner;
-
 public final class RootPrecision {
     private RootPrecision() {
     }
 
-    public static void main(String[] args) {
-        // take input
-        Scanner scn = new Scanner(System.in);
-
-        // n is the input number
-        int n = scn.nextInt();
-
-        // p is precision value for eg - p is 3 in 2.564 and 5 in 3.80870.
-        int p = scn.nextInt();
-        System.out.println(squareRoot(n, p));
-
-        scn.close();
-    }
-
-    public static double squareRoot(int n, int p) {
-        // rv means return value
-        double rv;
-
-        double root = Math.pow(n, 0.5);
-
-        // calculate precision to power of 10 and then multiply it with root value.
-        int precision = (int) Math.pow(10, p);
-        root = root * precision;
-        /*typecast it into integer then divide by precision and again typecast into double
-    so as to have decimal points upto p precision */
-
-        rv = (int) root;
-        return rv / precision;
+    /**
+     * Calculates the square root of a number with the specified precision.
+     *
+     * @param number    The number to calculate the square root of.
+     * @param precision The number of decimal places of precision.
+     * @return The square root of the number with the specified precision.
+     */
+    public static double calculateSquareRoot(int number, int precision) {
+        double rawRoot = Math.sqrt(number); // Calculate the square root using Math.sqrt
+        double scalingFactor = Math.pow(10, precision); // Calculate the scaling factor for precision
+
+        // Scale the square root, truncate the extra decimals, and rescale back
+        return Math.round(rawRoot * scalingFactor) / scalingFactor;
     }
 }

src/test/java/com/thealgorithms/others/RootPrecisionTest.java

@@ -0,0 +1,33 @@
+package com.thealgorithms.others;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+public class RootPrecisionTest {
+
+    @Test
+    public void testSquareRootWithZeroPrecision() {
+        assertEquals(2.0, RootPrecision.calculateSquareRoot(4, 0));
+        assertEquals(3.0, RootPrecision.calculateSquareRoot(9, 0));
+        assertEquals(5.0, RootPrecision.calculateSquareRoot(25, 0));
+    }
+
+    @Test
+    public void testSquareRootWithPrecision() {
+        assertEquals(1.414, RootPrecision.calculateSquareRoot(2, 3));
+        assertEquals(3.162, RootPrecision.calculateSquareRoot(10, 3));
+        assertEquals(5.000, RootPrecision.calculateSquareRoot(25, 3));
+    }
+
+    @Test
+    public void testSquareRootWithHighPrecision() {
+        assertEquals(1.41421, RootPrecision.calculateSquareRoot(2, 5));
+        assertEquals(3.16228, RootPrecision.calculateSquareRoot(10, 5));
+    }
+
+    @Test
+    public void testSquareRootOfZero() {
+        assertEquals(0.0, RootPrecision.calculateSquareRoot(0, 3));
+    }
+}