My code

%% Given vectors

v1 = [1, -2, 2, -1];

v2 = [-3, 5, -2, 2];

v3 = [-1, 1, 2, 0];

v4 = [0, -1, 4, -1];

% Creating matrix with columns as given vectors

A = [v1' v2' v3' v4'];

% Augmented matrix [A | I]

augA = [A eye(4)];

% Row-reduced form of augmented matrix

reduced_augA = rref(augA);

% Identify pivot columns

pivot_columns = find(reduced_augA(:, 1:4) ~= 0, 1);

% Extract basis vectors from the original matrix A

BasisMatrix = A(:, pivot_columns);

% Display the basis matrix

disp('Basis Matrix:');

disp(BasisMatrix);

My error "Variable BasisMatrix must be of size [4 4]. It is currently of size [4 1]. Check where the variable is assigned a value."

I cant seem to get it correct.