Roxanne - 6 months ago 29

Java Question

I have no idea how to get the median without this method, but it keeps saying conversion error. I know it's because I'm dividing the numbers.length by 2, but I can't figure out how to make the program understand it's a double. It's at the bottom where I keep getting the error. It's my last if else statement. I have searched everywhere so I'm sorry if this is a repeat, but I couldn't find one. I can't convert to ints either because my array consists of doubles. Thanks in advance to whoever helps me.

`import static java.lang.Math.*;`

import java.util.Scanner;

import java.util.Arrays;

public class ComputingArrays

{

public static void main(String[] args) {

Scanner in = new Scanner(System.in);

double [] numbers = {33.5, 67.5, 67.5, 88.0, 46.0, 94.5, 77.5, 83.0, 95.0, 80.5}; // declare, allocate memory, and store values

double n = numbers.length; // get length of array

Arrays.sort(numbers);

System.out.println("The Array of Numbers are :");

double sum = 0; //initiate and declare sum

for (int i = 0; i < n; i++) { //loop through n numbers

System.out.println(numbers[i]);

sum = sum + numbers[i];

}

final double average = sum / n;

System.out.println("The Sum of the Array is " + sum);

System.out.println("The Average of the Array is " + average);

double var1 = 0;

double var2 = 0;

double varSum = 0;

for (int i = 0; i < n; i++) {

var1 = numbers[i] - average;

var2 = var1 * var1; // to square

varSum = varSum + var2; // to get sum of all squared differences

}

double variance = varSum / n;

System.out.printf("The Variance of the Array is %.2f %n", variance); //%.2f rounds two decimal places

System.out.printf("The Standard Deviation is %.3f %n", Math.sqrt(variance));

double middle = numbers.length / 2.0;

double median = 0.0;

if (numbers.length % 2 == 1){

median = numbers[middle];

System.out.println("The median is " + median);

}

else {

median = (numbers[middle-1] + numbers[middle]) / 2;

System.out.println("The median is " + median);

}

}

}

Answer

```
import static java.lang.Math.*;
import java.util.Scanner;
import java.util.Arrays;
public class HelloWorld
{
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
double [] numbers = {33.5, 67.5, 67.5, 88.0, 46.0, 94.5, 77.5, 83.0, 95.0, 80.5}; // declare, allocate memory, and store values
double n = numbers.length; // get length of array
Arrays.sort(numbers);
System.out.println("The Array of Numbers are :");
double sum = 0; //initiate and declare sum
for (int i = 0; i < n; i++) { //loop through n numbers
System.out.println(numbers[i]);
sum = sum + numbers[i];
}
final double average = sum / n;
System.out.println("The Sum of the Array is " + sum);
System.out.println("The Average of the Array is " + average);
double var1 = 0;
double var2 = 0;
double varSum = 0;
for (int i = 0; i < n; i++) {
var1 = numbers[i] - average;
var2 = var1 * var1; // to square
varSum = varSum + var2; // to get sum of all squared differences
}
double variance = varSum / n;
System.out.printf("The Variance of the Array is %.2f %n", variance); //%.2f rounds two decimal places
System.out.printf("The Standard Deviation is %.3f %n", Math.sqrt(variance));
double middle = numbers.length / 2.0;
double median = 0.0;
int middleIndex = (int)middle;
if (numbers.length % 2 == 1){
median = numbers[middleIndex];
System.out.println("The median is " + median);
}
else {
median = (numbers[middleIndex-1] + numbers[middleIndex]) / 2;
System.out.println("The median is " + median);
}
}
}
```

**This prints out:**

The Sum of the Array is 733.0

The Average of the Array is 73.3

The Variance of the Array is 369.66

The Standard Deviation is 19.227

The median is 79.0