Replace numbers in list with strings from another list in Python

Question

I have a list of numbers and list of strings:

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:

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

I tried setting labels to

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.

Does this answer your question? Replace values in array of indexes corresponding to another array — Georgy
– Georgy, Commented Feb 25, 2020 at 19:47

Jean-François Fabre · Accepted Answer · 2019-12-15 17:36:54Z

1

simple list comprehension with offset correction (in that case you don't need a dictionary)

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:

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

answered Dec 15, 2019 at 17:36

Jean-François Fabre♦

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Comments

oppressionslayer · Accepted Answer · 2019-12-15 17:29:09Z

0

You can use numpy for this:

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']

answered Dec 15, 2019 at 17:29

oppressionslayer

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