R function rep() in Python (replicates elements of a list/vector)

Question

The R function rep() replicates each element of a vector:

> rep(c(\"A\",\"B\"), times=2)
[1] \"A\" \"B\" \"A\" \"B\"

This is like the list m

Answer 1

What do you think about this way?

To repeat a value:

>>> repetitions=[]
>>> torep=3
>>> nrep=5
>>> for i in range(nrep):
>>>     i=torep
>>>     repetitions.append(i)
[3, 3, 3, 3, 3]

To repeat a sequence:

>>> repetitions=[]
>>> torep=[1,2,3,4]
>>> nrep= 2
>>> for i in range(nrep):
>>>     repetitions=repetitions+torep
>>> print(repetitions)
[1, 2, 3, 4, 1, 2, 3, 4]

Answer 2

Here is my attempt at a clone of R rep:

def rep(x, times = 1, each = 1, length_out = None):
    if not isinstance(times, list):
        times = [times]

    res = ''.join([str(i) * each for i in x])

    if len(times) > 1:   
        res = ''.join(str(i) * m for i, m in zip(x, times))
    else:
        res = ''.join(res * times[0])
    
    if length_out is None:
        return res
    else:
        return res[0:length_out]

Reproduces the R examples:

rep(range(4), times = 2)
rep(range(4), each = 2)
rep(range(4), times = [2,2,2,2])
rep(range(4), each = 2, length_out = 4)
rep(range(4), each = 2, times = 3)

with the exception that there is no recycling of shorter vectors/lists (imo this is the worst feature of R).