How do you initialize an N*M matrix?

From the MATLAB help, it says to use:

    M = matrix(N, M)

but when I apply this it says that the function 'matrix' is not recognized.

Undefined function 'matrix' for input arguments of type 'double'.

Error in experimental (line 1)
M = matrix(3,3)

[per isakson]

What does

    which matrix

return?

[Harry]

'matrix' not found.

[Tulike]

M=zeros(N,M)

Answer 1

[Leah]

To initialize an N-by-M matrix, use the “zeros” function. For example, create a 3-by-5 matrix of zeros:

A = zeros(3,5);

You can then later assign specific values to the elements of “A”.

[Bogdan Goidescu]

ok,but,i have this problem:Write a program into a script file that creates a matrix m x n with elements that have the following values:

- The value of each element in the first line is the number of that column

- The value of each element in the first column is the line number

- Each of the other elements of the matrix have values ​​equal to the sum between the element above and the left element

[Abhishek Inamdar]

Use "X = ones(n)" and add the values based on the row and column. Use for loop to work on value addition

[israt fatema]

Can you please show me how to assign value to A after initialize the N x M matrix? For example i need to create a vector 5 x 5 and with values x = 20 35 49 64 23

Answer 2

[Lokesh Ravindranathan]

I am assuming you are trying to create an empty matrix of zeros of dimensions N*M. You can try the following instead

   M = zeros(3,3)

This creates a matrix of zeros of size 3*3.

[per isakson]

matrix is a function in the symbolic toolbox.

[Lokesh Ravindranathan]

Oh. Thanks Isakson. I will update my answer. My MATLAB did not have symbolic Math toolbox.

Answer 3

[Nitin]

you could initialize the matrix,

M = zeros(n,m);

Answer 4

[Pau]

This should make the trick

M = double.empty(N,M,0);

https://uk.mathworks.com/help/matlab/ref/empty.html

Answer 5

[Arun]

Here is the documentation for multi dementional arrays in matlab

https://www.mathworks.com/help/matlab/math/multidimensional-arrays.html

Here is an example to create and initialize a 3X3 matric

A = [1 2 3; 4 5 6; 7 8 9]

A = 3×3

1 2 3

4 5 6

7 8 9

It is simular to matrix in c programming.

Answer 6

[HARSHAVARTHINI]

% Define the matrix A = [4 1 9; 0 1 3; 0 1 2];

% Initialize parameters n = size(A, 1); % Size of the matrix x = rand(n, 1); % Initial guess for the eigenvector tolerance = 1e-6; % Convergence criteria max_iter = 1000; % Maximum number of iterations lambda_old = 0; % Initial eigenvalue

for k = 1:max_iter % Multiply matrix A with vector x y = A * x;

    % Normalize the vector
    x = y / norm(y);

    % Compute the Rayleigh quotient (dominant eigenvalue)
    lambda = x' * A * x;

    % Check for convergence
    if abs(lambda - lambda_old) < tolerance
        fprintf('Converged in %d iterations.\n', k);
        break;
    end

    % Update old eigenvalue
    lambda_old = lambda;
end

% Display results fprintf('Dominant Eigenvalue: %.6f\n', lambda); disp('Corresponding Eigenvector:'); disp(x);