Python Iterating n items of array at a time

Question

I have an array of ~1,000 integers which I want to iterate 50 items at a time and append to a string. I am not quite sure how to go about this in Python.

mystring = ""
for [every 50 items] in arr:
    string += 50 items
    print(string)

Is arr `numpy.array` or `pandas.DataFrame`? Or is it just a list? — Jab, Oct 12 '21 at 17:08
Does this answer your question? [Pandas - Slice large dataframe into chunks](https://stackoverflow.com/questions/44729727/pandas-slice-large-dataframe-into-chunks) — Jab, Oct 12 '21 at 17:16

score 4 · Accepted Answer · answered Oct 12 '21 at 17:11

4

You can split the list into slices to iterate over.

l = [ ... ]
for x in (l[i:i + 50] for i in range(0, len(l), 50)):
    print(x)

answered Oct 12 '21 at 17:11

Unmitigated

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score 1 · Answer 2 · edited Oct 12 '21 at 17:43

def chunks(arr: list, n: int) -> Generator:
    """
    Yield successive n-sized chunks from arr.
    :param arr
    :param n
    :return generator
    """
    for i in range(0, len(arr), n):
        yield arr[i:i + n]

you can use this function to create n-sized chunks from a array
for example:

list(chunks([1, 2, 3, 4], 2)) # => [[1,2],[3,4]]
in your case you can pass your array to function and pass 50 to second argument
after that do for loop on result of chunks function

Python Iterating n items of array at a time

2 Answers2