Variable number of input matrices in a function

I want to change the code below so the function blkdiag can take on any number of matrices A, based on the value of N.

N = 3;

A_1 = sparse(1:N,1:N,-1*ones(N,1),N,N+1);
A_2 = sparse(1:N,2:N+1,1*ones(N,1),N,N+1);
A = A_1+A_2;

out = full(blkdiag(A,A,A))

So suppose N=4, then

out = full(blkdiag(A,A,A,A))

And so on.

How can I create a variable input for this function, based on a value?

Thanks,

Tim

[madhan ravi]

A = {A_1+A_2};
A=repelem(A,N);
out = full(blkdiag(horzcat(A{:}))) % or
out = full(blkdiag(vertcat(A{:})))

[Tim de Reijer]

[1]

Your solution does not give the wanted answer.

full(blkdiag(A,A)) results in

    -1     1     0     0     0     0     0     0
     0    -1     1     0     0     0     0     0
     0     0    -1     1     0     0     0     0
     0     0     0     0    -1     1     0     0
     0     0     0     0     0    -1     1     0
     0     0     0     0     0     0    -1     1

While full(blkdiag(repmat(A,1,2))) gives

    -1     1     0     0    -1     1     0     0
     0    -1     1     0     0    -1     1     0
     0     0    -1     1     0     0    -1     1

[2]

Neither full(blkdiag(horzcat(A{:}))) nor full(blkdiag(vertcat(A{:}))) produces the same result as well..

[madhan ravi]

True , apologies didn't verify the results.

Answer 1

[Guillaume]

N = 4;

A_1 = sparse(1:N,1:N,-1*ones(N,1),N,N+1);
A_2 = sparse(1:N,2:N+1,1*ones(N,1),N,N+1);
A = A_1+A_2;

blkdiaginputs = repelem({A}, N);  %put your inputs in a cell array
out = full(blkdiag(blkdiaginputs{:}))  %and convert the cell array into a comma-separated list

Documentation about comma separated lists