Create 10. Array from list

Week 3: Objects, files and exceptions/10. Array from list

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+Write the method
+
+double[] newArray(ArrayList<Double> list)
+
+which takes a list of floats as its parameter. 
+The method creates and returns a floating point array with the same elements in the same order as the list.
+
+Example method call:
+
+public static void main(String[] args){
+    ArrayList<Double> test = new ArrayList<>();
+    test.add(1.0);
+    test.add(3.0);
+    test.add(2.75);
+
+    double[] array = newArray(test);
+    System.out.println("Array: " + Arrays.toString(array));
+}
+
+Program outputs:
+Array: [1.0, 3.0, 2.75]
+
+
+
+================
+
+
+import java.util.Random;
+import java.util.ArrayList;
+import java.util.Arrays;
+
+public class Test {
+    public static void main(String[] args) {
+        final Random random = new Random();
+        
+        
+        double[] decimalValues = {0, 0.25, 0.5, 0.75};
+        
+        for (int testNumber = 1; testNumber <= 3; testNumber++) {
+            System.out.println("Test " + testNumber);
+            ArrayList<Double> list = new ArrayList<>();
+            int size = random.nextInt(5) + 5;
+            for (int i = 0; i < size; i++) {
+                double element = random.nextInt(10) + decimalValues[random.nextInt(decimalValues.length)];
+                list.add(element);
+            }
+            
+            System.out.println("List: " + list);
+            double[] array = newArray(list);
+            System.out.println("Array: " + Arrays.toString(array));
+            System.out.println("");
+        }
+    }
+
+
+
+    // CONVERT LIST TO ARRAY
+    public static double[] newArray(ArrayList<Double> list) {
+        double[] array = new double[list.size()];
+        // for (int num: list) {
+        //     array[i] = num;
+        // }
+
+        // for list - need to get element using idx
+        for (int i = 0; i < list.size(); i++) {
+            array[i] = list.get(i);
+        }
+        return array;
+    }
+
+
+}
+
+
+
+
+
+
+
+Test 1
+List: [3.0, 6.25, 5.0, 4.75, 1.25, 8.75, 0.0, 7.0, 0.0]
+Array: [3.0, 6.25, 5.0, 4.75, 1.25, 8.75, 0.0, 7.0, 0.0]
+
+Test 2
+List: [2.25, 9.75, 7.25, 2.25, 7.5, 5.25, 9.0, 8.75]
+Array: [2.25, 9.75, 7.25, 2.25, 7.5, 5.25, 9.0, 8.75]
+
+Test 3
+List: [4.5, 5.75, 9.5, 5.0, 9.75]
+Array: [4.5, 5.75, 9.5, 5.0, 9.75]
+
+
+
+