"""

Buffer/array/list splitting module

-----------------------------------

| Copyright 2022 by Joel C. Alcarez |

| [[email protected]] |

|-----------------------------------|

| We make absolutely no warranty |

| of any kind, expressed or implied |

|-----------------------------------|

| Contact primary author |

| if you plan to use this |

| in a commercial product at |

| [email protected] |

-----------------------------------

"""

def altsplitbuf(buf: list[any]

) -> list[any]:

"""Split a list into two with

alternating items in

different lists

Args:

buf: list, array or tuple

Returns:

[[odd list], [even list]]

"""

m = len(buf)

if m % 2 == 0:

m -= m & 1

return [buf[:m - 1:2], buf[1: m: 2]]

def altsplitbuf3way(buf: list[any]

) -> list[any]:

"""Split a list into three with

alternating items in

different lists

Args:

buf: list, array or tuple

[red, green, blue, ...]

Returns:

[[red list],

[green list],

[blue list]]

"""

m = len(buf)

if m % 3 == 0:

m -= m & 1

return [buf[:m - 2:3], buf[1: m - 1: 3], buf[2: m: 3]]

def altsplitbufnway(buf: list[any],

n: int) -> list[any]:

"""Split a list into n with

alternating items in

different lists

Args:

buf: list, array or tuple

[red, green, blue, ...]

Returns:

[[red list],

[green list],

[blue list]]

"""

retval = []

m = len(buf)

j = n - 1

if m % n == 0:

m -= m & 1

for i in range(n):

retval += [buf[i: m - j: n]]

j -= 1

return retval