Split a Python list into chunks

Split a Python list into n chunks

In order to chunk a list into n smaller lists, you first need to calculate the size of each chunk, using math.ceil() and len(). Then, you can create a new list of size n using list() and range().

Finally, you can use map() to map each element of the new list to a chunk the length of size. If the original list can't be split evenly, the final chunk will contain the remaining elements.

from math import ceil

def chunk_into_n(lst, n):
  size = ceil(len(lst) / n)
  return list(
    map(lambda x: lst[x * size:x * size + size],
    list(range(n)))
  )

chunk_into_n([1, 2, 3, 4, 5, 6, 7], 4) # [[1, 2], [3, 4], [5, 6], [7]]

Split a Python list into chunks of a specified size

Similarly, you can chunk a list into smaller lists of a specified size. You can use the same approach as above, but instead of calculating the size of each chunk, you can use the specified size directly.

from math import ceil

def chunk(lst, size):
  return list(
    map(lambda x: lst[x * size:x * size + size],
      list(range(ceil(len(lst) / size)))))

chunk([1, 2, 3, 4, 5], 2) # [[1, 2], [3, 4], [5]]