MATLAB: Increment dates using for loop

datetime array increment

I'm trying to fill a variable sized datetime array. I then want the declared datetime value to fill the first 3 elements before incrementing by one to fill the next three.This process repeats until the desired sized element is reach. See current output & desired output.
Code:
samples = input("Number of Samples to Generate: ");
DateBuilt = repmat(datetime(0,0,0),samples,1);
t = datetime(2018,1,1);
DateBuilt(1) = t 
for i=1:samples
        if i <= 3
            DateBuilt(i) = t; 
        else
            t = t + 1;
            DateBuilt(i) = t;
end
Current Output:
Number of Samples to Generate: 14
DateBuilt = 
  14×1 datetime array
   01-Jan-2018 
   30-Nov--0001
   30-Nov--0001
   30-Nov--0001
   30-Nov--0001
   30-Nov--0001
   30-Nov--0001
   30-Nov--0001
   30-Nov--0001
   30-Nov--0001
   30-Nov--0001
   30-Nov--0001
   30-Nov--0001
   30-Nov--0001
Desired Output:
   Number of Samples to Generate: 14
DateBuilt = 
  14×1 datetime array
   01-Jan-2018 
   01-Jan-2018
   01-Jan-2018
   02-Jan-2018
   02-Jan-2018
   02-Jan-2018
   03-Jan-2018
   03-Jan-2018
   03-Jan-2018
   04-Jan-2018
   04-Jan-2018
   04-Jan-2018
   05-Jan-2018
   05-Jan-2018

Best Answer

Are there any other calculations being done in the loop body of your actual code? If not, this can be done without looping:
samples = input("Number of Samples to Generate: ");
days = floor((0:samples-1)./3)'+1;
dt = datetime(2018,1,days);
If you do really need to loop for some other reason, there are things that need to change in your code:
1) It's missing and end to the conditional block.
2) t = t+1 ends up incrementing the day every iteration.
samples = input("Number of Samples to Generate: ");
DateBuilt = repmat(datetime(0,0,0),samples,1);
t = datetime(2018,1,1);
DateBuilt(1) = t;
for i=1:samples
    DateBuilt(i) = t+days(floor((i-1)/3));
end
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