<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0-alpha1/dist/css/bootstrap.min.css" rel="stylesheet"
        integrity="sha384-GLhlTQ8iRABdZLl6O3oVMWSktQOp6b7In1Zl3/Jr59b6EGGoI1aFkw7cmDA6j6gD" crossorigin="anonymous">
    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.3.0/css/all.min.css"
        integrity="sha512-SzlrxWUlpfuzQ+pcUCosxcglQRNAq/DZjVsC0lE40xsADsfeQoEypE+enwcOiGjk/bSuGGKHEyjSoQ1zVisanQ=="
        crossorigin="anonymous" referrerpolicy="no-referrer" />
</head>
</html>
from operator import mul
from functools import reduce

import numpy as np
from numpy.random import randint
from numpy.lib import Arrayterator
from numpy.testing import assert_


def test():
    np.random.seed(np.arange(10))

    # Create a random array
    ndims = randint(5)+1
    shape = tuple(randint(10)+1 for dim in range(ndims))
    els = reduce(mul, shape)
    a = np.arange(els)
    a.shape = shape

    buf_size = randint(2*els)
    b = Arrayterator(a, buf_size)

    # Check that each block has at most ``buf_size`` elements
    for block in b:
        assert_(len(block.flat) <= (buf_size or els))

    # Check that all elements are iterated correctly
    assert_(list(b.flat) == list(a.flat))

    # Slice arrayterator
    start = [randint(dim) for dim in shape]
    stop = [randint(dim)+1 for dim in shape]
    step = [randint(dim)+1 for dim in shape]
    slice_ = tuple(slice(*t) for t in zip(start, stop, step))
    c = b[slice_]
    d = a[slice_]

    # Check that each block has at most ``buf_size`` elements
    for block in c:
        assert_(len(block.flat) <= (buf_size or els))

    # Check that the arrayterator is sliced correctly
    assert_(np.all(c.__array__() == d))

    # Check that all elements are iterated correctly
    assert_(list(c.flat) == list(d.flat))
