有没有办法通过python中的dict直接迭代一个系列？

Question

Trying to figure out the best way to iterate a series through a dictionary in pandas. Here is my MRE:

s1 = pd.Series(['a','b','c','d'])

d = {'a':1, 'b':2, 'c':3, 'd':4}

what I want to do is create s2 such that

s2 = pd.Series([1,2,3,4])

by processing s1 through d. So far, the best way I can think of is

s2 = pd.Series([d[item] for item in list(s1)])

I am aware of the option to do

s2 = pd.Series(d.values())

but the actual problem I am trying to solve would require passing the series through a dictionary.

Answer 1

You can use map :

s1 = pd.Series(['a','b','c','d'])
d = {'a':1, 'b':2, 'c':3, 'd':4}
s2 = s1.map(d)

output:

0    1
1    2
2    3
3    4

Answer 2

Try with replace

s2 = s1.replace(d)
s2
Out[17]: 
0    1
1    2
2    3
3    4
dtype: int64