Question

//please help I can’t figure out how to print and can’t get the random numbers to print. Please help, I have the prompt attached. Thanks

import java.util.*;

public class Test {

/** Main method */

public static void main(String[] args) {

double[][] matrix = getMatrix();

// Display the sum of each column

for (int col = 0; col < matrix[0].length; col++) {

System.out.println(

"Sum " + col +

" is " + sumColumn(matrix, col));

}

}

/** getMatrix initializes an array with user input values */

public static double[][] getMatrix() {

final int ROWS = 3;

final int COLUMNS = 2;

double[][] m = new double[ROWS][COLUMNS];

// Prompt the user to enter a 3-by-4 matrix

for (int row = 0; row < m.length; row++)

for (int col = 0; col < m[row].length; col++)

System.out.println(20+(int) (Math.random() *50));

return m;

}

/** sum returns the sum of the elements in columnIndex */

public static double sumColumn(double[][] m, int columnIndex) {

double sum = 0;

for (int row = 0; row < m.length; row++) {

sum += m[row][columnIndex];

}

return sum;

}

}

Create a Java class program named XXXX_Program2.java. Please note the file name is case sensitive and it must be the same as the class name in your Java program. (method +1D array+ 2D array) Write a Java program to meet the following requirements 1. The program generates random numbers(between 20.0 to 50.0) into a 3(row)-by-2(column) matrix in double type. 2. Have below method to create the array: public static double[][] createArray() 3. Have below method to sum of each column: public static double sumColumn (double[][ m, int columnIndex) 4. Have below method to display the matrix, the sum and average of each column. All the numbers should be aligned well. Hint: Print numbers in %6.1f format. public static void printResult (double[ ][] m, double[] sum) 5. Print the max and min numbers of the matrix with their column and row positions. .Below is an example of output Output The matrix is 43.1 44.7 45.2 25.7 26.4 29.8 81.9 27.3 Sum: 133.1 Avg: 44.4 The maximum number is 45.2 at row 2, column 0 The minimum number is 25.7 at row 0, column 1 Program 2 is developed by <your Kean email ID>.

Answer 1

I have done the first 4 parts of the problem. The last part is trivial and can be added easily in the code

import java.util.*;
public class Test {
/** Main method */
public static void main(String[] args) {
double[][] matrix = createArray();
double[] sum = new double[matrix[0].length];
for (int i = 0; i < matrix[0].length; i++) {
sum[i] = sumColumn(matrix, i);
}
printResult(matrix, sum);
}

/** getMatrix initializes an array with user input values */
public static double[][] createArray() {
final int ROWS = 3;
final int COLUMNS = 2;
double[][] m = new double[ROWS][COLUMNS];

// Create a random 3-by-2 matrix
for (int row = 0; row < ROWS; row++)
for (int col = 0; col < COLUMNS; col++)
// For every element of the 3x2 matrix
m[row][col] = 20 + (Math.random() * 30); // Genereate a random double between 20 and 50 and insert it into the matrix
return m;
}
  
/** sum returns the sum of the elements in columnIndex */
public static double sumColumn(double[][] m, int columnIndex) {
double sum = 0;
for (int row = 0; row < m.length; row++) {
sum += m[row][columnIndex];
}
return sum;
}
  
/* print the matrix */
public static void printResult(double[][] m, double [] sum) {
System.out.println("The matrix is: ");
for(int row = 0; row < m.length; row++) {
System.out.printf(" ");
for(int col = 0; col < m[0].length; col++) {
System.out.printf("%6.1f ", m[row][col]);
}
System.out.print("\n");
}
System.out.printf("Sum: ");
for (int i = 0; i < sum.length; i++) {
System.out.printf("%6.1f ", sum[i]);
}
  
}
}
  

Output:

The matrix is: 32.2 49.7 38.3 Sum: 120.2 24.3 40.2 22.8 87.3