Python/Numpy : How do I renumber an existing array with repeating instances?

Question

这个问题已经有答案了:

Vectorized relabeling of NumPy array to consecutive numbers and retrieving back (1 个回答)

已关闭 3 年前。

我有以下数组:(3,2,3,4,7,2,4,7)*我需要将其重新编号为:(1,0,1,2,3,0,2,3)

即:最低值应变为 0，第二低值应变为 1，依此类推

我能找到的类似帖子每个数字只有一个实例，并且相关答案不适用于此处，因为重复的数字应该具有相同的重新编号值。

谢谢

• 实际数组有数千个数字。

Answer 1

这可能不是最有效的解决方案，因为我怀疑其中有一些俏皮话，但我希望它是明智且直接的:

from collections import defaultdict

ary = [3,2,3,4,7,2,4,7]

#you don't need a defaultdict, but I like to use them just in case, instead of a dictionary, as a general practice
rank = defaultdict(int)

for x in ary: #first, we get all the values of the array and put them in the dict
    rank[x] = 0

count = 0

for x in sorted(rank): #now we go from lowest to highest in the array, adding 1 to the dict-value
    rank[x] = count
    count += 1

ary = [rank[x] for x in ary]

print(ary)