MATLAB: I cant CREATE array the rand() in for loop….. Firstly, generate 72 bit binary number in 20 times. After, i need use the second, tenth or fifth generated random binary number.

array define in rand()

But, error:
In an assignment  A(I) = B, the number of elements in B and I must be the same.
Error in ga_function2 (line 9)
        random_chromosome(popSize) = round(rand(1, 72));
random_chromosome = [1;20];
for popSize = 1 : 1 : 20
        random_chromosome(popSize) = round(rand(1, 72));
end

Best Answer

Because popSize is scalar, the code
random_chromosome(popSize)
refers to one element of the array random_chromosome, but rand(1, 72) is an array with 72 elements.
You are trying to fit seventy-two elements into the space of one element in a matrix, which obviously does not fit and causes the error. One better solution would be to avoid that inefficient loop altogether:
X = randi(2,20,72)-1;
produces a matrix X of size 20x72, where each row corresponds to one of your "random binary number". For example the second number is simply the second row:
X(2,:)
You can learn more about basic MATLAB usage by doing these tutorials:
http://www.mathworks.com/help/matlab/getting-started-with-matlab.html
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