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How to find transpose of a 2D Matrix in C++

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Explanation of the code:

Since we are using a 2-D array, we need to use a nested for loop to traverse through it.

First, initialize your 2-D array.
Run a nested for loop. The outer for loop will iterate through rows and the inner loop will iterate through columns.
While accessing element arr[row][col], insert the element into transpose[col][row], i.e., switch the rows and columns. For example,
arr[0][1] will be placed at transpose[1][0], so two and four will swap positions in the transpose matrix.
The for loop will iterate through every element and insert it into the correct index in the transpose 2-D array.

#include<iostream>
using namespace std;
// user defined function to print 2 day array with correct format
void printArr (int arr[][3], int columns)
{
    for(int i = 0; i < 3; i++)
    {
        for(int j = 0; j < columns; j++)
        {
            cout << arr[i][j] << " ";
        }
        cout << endl;
    }
}
int main()
{
    // declare matrix
	const int rows = 3;
	const int columns = 3;
	int arr[rows][columns] = {1, 2, 3,
                              4, 5, 6, 
                              7, 8, 9};
    // declare transpose matrix of same size                       
    int transpose[rows][columns];
	cout << "Original Matrix: " << endl;
	printArr(arr, columns);
    // outer for loop to traverse rows
	for(int i = 0; i < rows; i++)
    {
        // inner for loop to traverse column
        for(int j = 0; j < columns; j++)
        {
            // insert arr[row][col] to transpose[col][row]
            transpose[j][i] = arr[i][j];
        }
    }
	cout<< "Transpose Matrix: " << endl;
	printArr(transpose, columns);
return 0;
}

RELATED TAGS

transpose

c++

matrix

CONTRIBUTOR

Sarah Tanveer

License: Creative Commons-Attribution-ShareAlike 4.0 (CC-BY-SA 4.0)

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How to find transpose of a 2D Matrix in C++

What is the transpose of a matrix?

Explanation of the code: