e specify don't
% have to be within those of the original operator. In fact, we can specify
% indices that don't overlap at all with the original operator, and we will
% simply end up with a larger operator. Zero out part of A:

A(1:2,:) = 0;
double(A)

%%
% Assign a new operator, C, to a subset of B:

C = opOnes(2,2);
B(2:3,1:2) = C;
double(B)

%% Creating More Complex Operators
% Spot operators can be combined into more complex operators using methods
% such as blkdiag and kron. Whenever a matrix is passe