find transpose of a matrix in java

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In this post, we will see how to find transpose of matrix in java.
Transpose of matrix?
A matrix which is created by converting all the rows of a given matrix into columns and vice-versa.
Below image shows example of matrix transpose.

So as you can see we have converted rows to columns and vice versa.

Java program to find transpose of matrix:

package org.arpit.java2blog;

/**
@author Arpit Mandliya
 */
public class TransposeMatrixMain {
 public static void main(String args[]) {
 // initialize the variable
 int[][] a = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 },{10, 11, 12} };

 // This will store resultant transpose matrix
 int[][] transposeMtrx=new int[a[0].length][a.length];
 // print the original matrix
 System.out.println("Original matrix:");
 for (int i = 0; i < 4; i++) {
 for (int j = 0; j < 3; j++) {
 System.out.print(" "+a[i][j]);
 }
 System.out.println();
 }

 // Performing transpose operation
 for (int i = 0; i < 4; i++) {
 for (int j = 0; j < 3; j++) {
 transposeMtrx[j][i] = a[i][j];
 }
 }
 System.out.println("======================");
 System.out.println("Transpose matrix:");
 // print transpose matrix
 for (int i = 0; i < 3; i++) {
 for (int j = 0; j < 4; j++) {
 System.out.print(" "+transposeMtrx[i][j]);
 }
 System.out.println();
 }
 }
}

When you run above program, you will get below output:

Original matrix:
 1 2 3
 4 5 6
 7 8 9
 10 11 12
======================
Transpose matrix:
 1 4 7 10
 2 5 8 11
 3 6 9 12