对 NumPy 数组中连续值的切片求和
问题描述
假设我有一个包含 10 个值的 numpy 数组 a.这里只是一个示例情况，尽管我想对长度为 100 的数组重复相同的操作.
Let's say I have a numpy array a containing 10 values. Just an example situation here, although I would like to repeat the same for an array with length 100.
a = np.array([1,2,3,4,5,6,7,8,9,10])
我想将前 5 个值与后 5 个值相加，以此类推，并将它们存储在一个新的空列表中，例如 b.
I would like to sum the first 5 values followed by the second 5 values and so on and store them in a new empty list say b.
所以 b 将包含 b = [15,40].
我该怎么做呢?
解决方案
试试这个列表推导:
b = [sum(a[current: current+5]) for current in xrange(0, len(a), 5)]
它一次从列表中取出 5 个切片，将它们相加并构造一个列表.也适用于长度不是 5 的倍数的列表.
It takes slices of 5 at a time from the list, sums them up and constructs a list. Also works for lists which aren't a multiple of 5 in length.
(xrange在python3+中应该是range)
(xrange should be range in python3+)
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