Write a method that sums all the numbers in the major diagonal in an n x n matrix of double values using the following header: public static double sumMajorDiagonal (double[][] m) Write a test program that first prompts the user to enter the dimension n of an n x n matrix, then asks them to enter the matrix row by row (with the elements separated by spaces). The program should then print out the sum of the major diagonal of the matrix.

Question

Jeremiah

Computers & Technology

5 August, 22:19

Write a method that sums all the numbers in the major diagonal in an n x n matrix of double values using the following header: public static double sumMajorDiagonal (double[][] m) Write a test program that first prompts the user to enter the dimension n of an n x n matrix, then asks them to enter the matrix row by row (with the elements separated by spaces). The program should then print out the sum of the major diagonal of the matrix.

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Elsie Mcintyre · Answer 1

Following are the code to this question:

import java. util.*; / /import package for user input

public class Main / /defining main class

{

public static double sumMajorDiagonal (double [][] m) / /defining method sumMajorDiagonal

{

double sum = 0; / /defining double variable sum

int i, j; / /defining integer variable

for (i = 0; i
{

for (j = 0; j < m. length; j++) / /defining loop to count column

{

if (i = = j) / /defining condition to value of i is equal to j

{

sum=sum + m[i][j]; / /add diagonal value in sum variable

}

}

}

return sum; / /return sum

}

public static void main (String args[]) / /defining main method

{

int n, i, j; / /defining integer variable

System. out. print ("Enter the dimension value: "); / /print message

Scanner ox = new Scanner (System. in); / /creating Scanner class object for user input

n = Integer. parseInt (ox. nextLine ()); / /input value and convert value into integer

double m[][] = new double[n][n]; / /defining 2D array

for (i = 0; i < m. length; i++)

{

String t = ox. nextLine (); / / providing space value

String a[] = t. split (" "); / / split value

for (j = 0; j < a. length; j++) / /defining loop to count array value

{

double val = Double. parseDouble (a[j]); / /store value in val variable

m[i][j] = val; / /assign val in to array

}

}

double d_sum = sumMajorDiagonal (m); / /call method store its return value in d_sum variable

System. out. println ("diagonal matrix sum: " + d_sum); / /print sum

}

}

output:

Enter the dimension value: 3

1 2 3

1 2 3

1 2 4

diagonal matrix sum: 7.0

Explanation:

Program description:

In the given java language code, a method "sumMajorDiagonal" is declared, that accepts a double array "m" in its parameter, inside the method two integer variable "i and j" and one double variable "sum" is defined, in which variable i and j are used in a loop to count array value, and a condition is defined that checks its diagonal value and use sum variable to add its value and return its value. In the main method first, we create the scanner class object, that takes array elements value and passes into the method, then we declared a double variable d_sum that calls the above static method, that is "sumMajorDiagonal" and print its return value with the message.