本文所需的函数：
arraySlice(axis, start, end, step)
Creates a subarray by slicing out each position along the given axis from the 'start' (inclusive) to 'end' (exclusive) by increments of 'step'. The result will have as many dimensions as the input, and the same length in all directions except the slicing axis, where the length will be the number of positions from 'start' to 'end' by 'step' that are in range of the input array's length along 'axis'. This means the result can be length 0 along the given axis if start=end, or if the start or end values are entirely out of range.
创建一个子数组，沿着给定的轴从'开始'（包括）到'结束'（不包括）按'步长'的增量切出每个位置。结果将具有与输入相同的维度，并且在所有方向上具有相同的长度，除了切片轴之外，长度将是沿'轴'的输