MATLAB: Command and Control vectors

MATLAB

I am having trouble trying to make this work. I want it so that whenever a value in t is 1, it will output five zeros onto a row vector. Whenever the value of t is 2, I want it to output 5 ones to the same row vector. When the value of t is 3, I want it to output 5 twos onto the row vector. I want it so that my ending vector will be [0 0 0 0 0 1 1 1 1 1 0 0 0 0 0 1 1 1 1 1 0 0 0 0 0 2 2 2 2 2]. Right now, it is only showing [0 1 0 1 0 2], so basically it is only outputting the value that I want once. How can I make it output the same number that I want 5 times instead of just once?
t = [1, 2, 1, 2, 1, 3];
d = 0;
for n = 1:length(t)
    if (t(n) == 1)
        for k = 0:4
            k = k+1;
            d(n) = 0;
        end
        
    elseif (t(n) == 2)
         for k = 0:4
           k = k+1;
            d(n) = 1; 
        end
        
    elseif (t(n) == 3)
         for k = 0:4
        k = k+1;
          d(n) = 2;
        end
    end
end
display(d)

Best Answer

A 'correct' version of your code, with all the pointless loops could be:
t = [1, 2, 1, 2, 1, 3];
d = zeros(1, numel(t)*5);  %at least predeclar d with the correct size.


idx = 1;                   %to keep track of where we are in d


for n = 1 : numel(t)
    if t(n) == 1            %note that using switch ... case statements would be more elegant than if.. elseif...

        for k = 1:5
            d(idx) = 0;
            idx = idx + 1;
        end        
    elseif t(n) == 2
         for k = 1:5
            d(idx) = 1;
            idx = idx + 1;
         end        
    elseif ((n) == 3
         for k = 1:5
            d(idx) = 2;
            idx = idx + 1;
         end
    end
end
display(d)
Now of course, the k loops are completely pointless, so we could simplify that to:
t = [1, 2, 1, 2, 1, 3];
d = zeros(1, numel(t)*5);  %at least predeclar d with the correct size.
idx = 1;                   %to keep track of where we are in d
for n = 1 : numel(t)
    if t(n) == 1           %note that using switch ... case statements would be more elegant than if.. elseif...
        d(idx:idx+4) = 0;
        idx = idx + 5;
    elseif t(n) == 2
        d(idx:idx+4) = 1;
        idx = idx + 5;
    elseif ((n) == 3
        d(idx:idx+4) = 2;
        idx = idx + 5;
    end
end
display(d)
Now of course, we're just repeating the same code in each of the if with the only difference being the value assigned, so they're also completely pointless:
t = [1, 2, 1, 2, 1, 3];
d = zeros(1, numel(t)*5);  %at least predeclar d with the correct size.
idx = 1;                   %to keep track of where we are in d
for n = 1 : numel(t)
    d(idx:idx+4) = t(n)-1;
    idx = idx + 5;
end
display(d)
An of course, even the for loop is pointless. As per Stephen's answer you can use kron, or you can use repelem:
t = [1, 2, 1, 2, 1, 3];
d = repelem(t-1, 5)
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