MATLAB: Ho to implement Sets in matlab

sets

hey everybody,, how to use Matlab in the set. problem: A = {1,2}, A ^ 2 = {(1,1), (1,2), (2,2) (2,1)};
how to find A ^ 100 by using Matlab?

Best Answer

    P = 100;
    A = uint8([1, 2]);    %if your stored values exceed 255 then change the uint8 to suit
    lenA = length(A);
    if lenA <= intmax('uint8')
      sstype = 'uint8';
    elseif lenA <= intmax('uint16')
      sstype = 'uint16';
    elseif lenA <= intmax('uint64')
      sstype = 'uint64';
    else
      error('A is too large to be able to subscript into. How did you even manage to create it??');
    end
    num_AP = lenA^P;
    try
      AP = zeros(num_AP, P, class(A));
    catch
      whoA = whos('A');
      bytes_per_entry = whoA.bytes ./ lenA;
      A_bytes_required = num_AP * P * bytes_per_entry;
      error('You need to install more memory; you need at least %g bytes of memory', A_bytes_required);
    end
    T = zeros(1, P, sstype);
    for J = 1 : num_AP
      AP(J,:) = A(T+1);
      for K = P : -1 : 1
        if T(K) ~= lenA - 1
          T(K) = T(K) + 1;
          break;
        else
          T(K) = 0;
        end
      end
    end
On my system, the maximum that can be constructed is for P = 28, which needs about 6.7 gigabytes.
As far as I know, there are no implementations of the x64 architecture that have more than 48 memory pins. In the case where A is a matrix with only 2 elements, that would give a maximum of P = 42, because 2^43 * 43 entries * 1 byte/entry > 2^48 bytes. However, I wrote the code assuming that you have access to a classified computer with memory capacities exceeding 2*10^9 times as much information stored on Earth as of 2013. (Don't tell me if I am wrong -- I am not authorized to know.)
The code was designed to reduce the memory requirements, not for efficiency.
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