Renaming column name based on its value Pandas

Question

I have the following data frame.

df 

col_1    col_2     col_3
min1     max1     target1
min2     max2     target2

I would like to rename columns col_1, col_2, col_3 based on their value as Min, Max, and Target respectively. I would like to have something below as a result.

Min     Max     Target
min1    max1    target1
min2    max2    target2

Can anyone show me a simple trick to do this using Pandas python?

For example, for col_0 it has value min1 and min2. Based on this min1 and min2 value rename the column as Min. Since it has those names under it. — , Mar 25 '20 at 09:37
@jezrael My Table is really big and I would like to create a rule to do that. In your case, it was simple. — , Mar 25 '20 at 09:38
@Kapital - OK, but how is possible distinguish what column is filled by minimal values, what column by maximal, what column is filled by target? Is possible explain more? — jezrael, Mar 25 '20 at 09:40
@Vishnudev In my case, col_1 don't have both of them. But what if we create a rule? Something like if the data frame columns have the word ```min``` inside it rename the column as a "Min" whatever value inside it? — , Mar 25 '20 at 09:45
It's not a good practise to depend on the values for columns because it might cause inconsistency in further code. You won't be sure of the column names. Suppose there is a column with value `target1start1` what would you rename it as? `target` or `target1` or `targetstart`. — Vishnudev Krishnadas, Mar 25 '20 at 09:49
@Kapital - Are you sure not exist 2 columns with `min` substring? — jezrael, Mar 25 '20 at 09:50
@Vishnudev Is that possible to do some regular expression for that to extract the word target only whatever the combination of words we have? — , Mar 25 '20 at 09:52
@jezrael You said it is duplicate and you provided me a link on top of my post but my question and the solution you provided me are completely different. I saw that solution before I post this question. Could you please remove that? — , Mar 25 '20 at 10:01
So u wanted MAX of the column max. And likewise for the column min. — letdatado, Apr 24 '22 at 01:00

score 2 · Answer 1 · answered Mar 25 '20 at 13:10

Well, I am not sure that you should rename columns this way, but here is a way you could do it. First remove numbers from string and then use the most common string.

from collections import Counter

cols = [Counter(df[col].str.replace('\d+', '')).most_common()[0][0].capitalize()
        for col in df.columns
        ]

df.columns = cols

Output:

    Min     Max     Target
0   min1    max1    target1
1   min2    max2    target2

Renaming column name based on its value Pandas

1 Answers1