用 Python 中另一个列表中的字符串替换列表中的数字

Question

I have a list of numbers and list of strings:我有一个数字列表和字符串列表：

data = [1, 2, 3, 1, 3]
labels = ['a','b','c']

How do I replace the numbers in data with the labels so that I will get data equals:如何用标签替换数据中的数字，以便获得数据等于：

['a','b','c','a','c']

I tried setting labels to我尝试将标签设置为

mappings [('a', 1), ('b',2), ('c',3)]

and using a for loop to replace the data variable but I cannot seem to replace a list.并使用 for 循环替换数据变量，但我似乎无法替换列表。

Answer 1

simple list comprehension with offset correction (in that case you don't need a dictionary)带有偏移校正的简单列表理解（在这种情况下，您不需要字典）

data = [1, 2, 3, 1, 3]
labels = ['a','b','c']    

>>> [labels[i-1] for i in data]
['a', 'b', 'c', 'a', 'c']

with a dictionary:用字典：

mappings = {1: 'a', 2: 'b', 3: 'c'}
>>> [mappings[i] for i in data]
['a', 'b', 'c', 'a', 'c']

Answer 2

You can use numpy for this:您可以为此使用 numpy：

import numpy as np
import itertools
np.array(labels)[[a - b for a,b in zip(data, itertools.cycle([1]))]].tolist() 

#  ['a', 'b', 'c', 'a', 'c']