Question

我有一个数字列表：

a=[6,8,1,0,5,0]

并且我需要以升序排序的顺序从原始列表中获取索引列表，除了这样的0个元素：

index=[3,4,1,0,2,0]

Answer 1

a = [6, 8, 1, 0, 5, 0]

sorted_positions = {x: i for i, x in enumerate(sorted(a))}
# {0: 1, 1: 2, 5: 3, 6: 4, 8: 5}

indices = [sorted_positions[x] for x in a]
# [4, 5, 2, 1, 3, 1]

zeroes = a.count(0)
# 2

answer = [
    0 if x == 0
    else i - zeroes + 1
    for i, x in zip(indices, a)
]
# [3, 4, 1, 0, 2, 0]

如果您不认识语法，则应搜索的术语：列表理解，字典理解和python三元运算符。

对于a=[3,3,1,1,2,2]，给出[6, 6, 2, 2, 4, 4]。

Answer 2

使用numpy的argsort可以使此问题具有一定的美感

text = "   I love   python    e  "

out = ""

string_started = False
underscores_to_add = 0
for c in text:
    if c == " ":
        underscores_to_add += 1
    else:
        if string_started:
            out += "_" * underscores_to_add
        underscores_to_add = 0
        string_started = True
        out += c

print(out)  # prints "I_love___python____e"

如何获取除Python中某些值以外的排序数组的索引？

2 个答案: