You can reproduce the syntax of the rep function in R fairly closely by first defining a function as follows:

```
function [result]=rep(array, count)
matrix = repmat(array, count,1);
result = matrix(:);
```

Then you can reproduce the desired behavior by calling with either a row or column vector:

```
>> rep([1 2 3],3)
ans =
1 1 1 2 2 2 3 3 3
>> rep([1 2 3]',3)
ans =
1 2 3 1 2 3 1 2 3
```

Note I have used the transpose (‘) operator in the second call to pass the input array as a column vector (a 3×1 matrix).

I benchmarked this on my laptop, and for a base array with 100,000 elements repeated 100 times, it was between 2 to 8 times faster than using the ceil option above, depending on whether you want the first or the second arrangement.