if we enter n rows and m colums and gets the output of 2n rows and 2m columns

Write a function named blocks that takes two positive integers, n and m, as input arguments (the function does not have to check the format of the input) and returns one matrix as an output argument. The function needs to return a 2n-by-2m matrix where the upper right and lower left n-by m sub matrices are all zeros and the rest of the matrix are all ones.

Answer 1

[Andrei Bobrov]

Please read about MATLAB functions: ones and blkdiag.

[jawad]

Dear Andrei Bobrov My name is Jawad Durrani and I am doing MS in electrical communication. I have completed my course work and doing research now a days. I am learning Matlab for my research. I am studying the book "Computer Programming with Matlab by Michael Fitzpatrick and Akos Ledeczi" This is not my homework. Its one of the exercise problem. I already done by using built in function zeros and ones But i want to do it without using built in functions I hope you understand. Regards

[Andrei Bobrov]

n = 5;
m = 3;
out = zeros([n m]*2);
for jj = 1:2
    out((jj-1)*n+(1:n),(jj-1)*m+(1:m)) = 1; 
end

Answer 2

[Patricio Mosquera]

Just choose your n and m

A = [1 0 ; 0 1];
B = ones([n, m]);
out = kron(A,B);

[DGM]

This answer works.

Answer 3

[ANAMIKA YADAV]

function out=blocks(n,m);
out=zeros([n m]*2);
out(3:4,1:3)=1;
out(1:2,4:6)=1;

[DGM]

Not only does this presume that the input is always (2,3), the output is wrong regardless of the input. What's the point in posting an answer if you aren't going to even test to see if it works?

Answer 4

[Himanshu Gabhane]

function out=blocks(n,m)
out=zeros([n m]*2);
out(end/2+1:end,1:end/2)=1;
out(1:end/2,end/2+1:end)=1;
end

[DGM]

While this at least calculates the output based on the input parameters (unlike @ANAMIKA YADAV's answer), the result is still completely inverted.

Answer 5

[SWAPAN KUMAR]

function result = blocks(n,m)
    % create a matrix of ones of size n x m
    ones_matrix =ones([n,m]);
    
    % create a matrix of zeros of size n x m
    zeros_matrix = zeros([n,m]);
    
    % create a matrix of ones of size n x m and concatenate it with a matrix of zeros of size n x m
    top_row = [ones_matrix zeros_matrix];
    
    % create a matrix of zeros of size n x m and concatenate it with a matrix of ones of size n x m
    bottom_row = [zeros_matrix ones_matrix];
    
    % concatenate the top row and bottom row vertically to create a 2n x m matrix
    matrix_first_half = [top_row; bottom_row];
    
    % concatenate the bottom row and top row vertically to create a 2n x m matrix
    matrix_second_half = [bottom_row; top_row];
    
    % concatenate the first half and second half horizontally to create a 2n x 2m matrix
    result = [matrix_first_half matrix_second_half];
end

[DGM]

This creates the correct result, then it duplicates it and concatenates again, so the output is twice as wide as it should be. Why all the extra baloney that wasn't even part of the assignment? Just delete the unnecessary stuff and you're back to a correct result.

function result = blocks(n,m) % n,m are backwards by requirement
    % create a matrix of ones of size n x m
    ones_matrix =ones([n,m]);
    
    % create a matrix of zeros of size n x m
    zeros_matrix = zeros([n,m]);
    
    % create a matrix of ones of size n x m and concatenate it with a matrix of zeros of size n x m
    top_row = [ones_matrix zeros_matrix];
    
    % create a matrix of zeros of size n x m and concatenate it with a matrix of ones of size n x m
    bottom_row = [zeros_matrix ones_matrix];
    
    % concatenate the top row and bottom row vertically to create a 2n x m matrix
    result = [top_row; bottom_row];
end