How can I check this matrix is the correct size?

I am wondering if this code is the correct code to check if the matrix is 18x4.

I think all it does is check if it has 18 rows, but does it check if it has 4 columns?

(initial4 should be an 18x4 matrix)

sz= size(initial4);
if (sz ~= 18)
    fprintf("Vector must be an 18x4 matrix.");
end

Answer 1

[Ameer Hamza]

Use this for checking the size

if ~isequal(size(M1), [18 4])

For example

M1 = rand(18, 4);
M2 = rand(18, 3);

if ~isequal(size(M1), [18 4])
    fprintf("Matrix M1 must be an 18x4 matrix.\n");
end

if ~isequal(size(M2), [18 4])
    fprintf("Matrix M2 must be an 18x4 matrix.\n");
end

Result

Matrix M2 must be an 18x4 matrix.

[Heather Spain]

Thank you, that worked!

[Ameer Hamza]

Glad to be of help.

Answer 2

[kevin harianto]

what if you want to check if the size of the matrix is too small?