Question

我有两个整数列表：例如

a = [ 008, 016, 024... ]

b = [001, 002, 002, 003... 012, 016]

一致地列出增量8，而列表b更随机（例如，有时两个记录的内容）。

基本上我想要做的是产生一个连接这两个的字典，这样a [i] = b [i]＆lt; = a [i + 1]它被附加到这样的？

所以我会从b：

获得

c = [ 008, 008, 008, 008 ... 016, 016]

希望这有意义吗？

Answer 1

我想你正在寻找这样的东西：

>>> a = [ 8, 16, 24, 32 ]
>>> b = [1, 2, 2, 3, 12, 16]
>>> [a[0] if a[0] < x and [a.pop(0)] else a[0] for x in b ]
[8, 8, 8, 8, 16, 16]

使用collections.deque：

>>> from collections import deque
>>> d = deque(a)
>>> [d[0] if d[0] < x and [d.popleft()] else d[0] for x in b ]
[8, 8, 8, 8, 16, 16]

一个非常易读的版本：

>>> it = iter(a)
>>> prev = next(it)
>>> result = []
for x in b:
    if x <= prev:
        result.append(prev)
    else:
        prev = next(it)
        result.append(prev)
...         
>>> result
[8, 8, 8, 8, 16, 16]

Answer 2

作为发电机：

def make_c(a, b):
    a_idx = 0
    for elt in b:
        # while loop can be replaced with "if"
        # as long as jumps in b never skip elements in a
        while elt > a[a_idx]: 
            a_idx += 1
        yield a[a_idx]

在python中链接两个不同长度的相关列表

2 个答案: