Replace part of string with a different column's value pandas + python

Question

The Problem

I have a CSV file full of data like this

 rowid       filepath              curr_time    cameraid    old_cameraid
    0        1/1_20180625_234436.jpg    2018-06-25 23:44:36 1       19
    1        1/1_20180626_005104.jpg    2018-06-26 00:51:04 1       19
    2        1/1_20180626_015735.jpg    2018-06-26 01:57:35 1       19
    3        1/1_20180626_030430.jpg    2018-06-26 03:04:30 1       19
    ...
    2605    2/2_20180622_064322.jpg     2018-06-22 06:43:22 2       64
    2606    2/2_20180622_074326.jpg     2018-06-22 07:43:26 2       64
    2607    2/2_20180622_084332.jpg     2018-06-22 08:43:32 2       64

What I want to do

I want to use the old_cameraid string value to replace the filepath number:

rowid   filepath    curr_time   cameraid    old_cameraid
0       19/19_20180625_234436.jpg       2018-06-25 23:44:36 1    19
...
2605    64/64_20180622_064322.jpg       2018-06-22 06:43:22 2       64

What I've tried

I've tried using

df.apply(lambda x: x['filepath'].replace('a',x['b']), axis=1)

from this This StackOverflow question but I'm not replacing the 'a', but instead a part of the string in the filepath column. Therefore, this wasn't working and I'm not sure.

I also apologize for the formatting of the rows. I tried to search how to properly format rows in a stackoverflow question but could not find the correct information.

Do you have more information on the initial formatting of the 'filepath' column? Specifically, is it always '#/#_...', where '#' is a single-digit number? — PMende
– PMende, Commented Aug 6, 2018 at 17:22
It is not always a single digit number but it is always the same number as the number in "cameraid". I want to replace it with the number in "old_cameraid" — sshah98
– sshah98, Commented Aug 6, 2018 at 17:23

sshah98 · Accepted Answer · 2018-08-06 17:41:56Z

2

You can add them all together, i assumed all filepath have the same syntax

1/1_20180625_234436.jpg

df['filepath'] = df['old_cameraid'].astype(str) + '/' + df['filepath'].astype(str).map(lambda x: x.split('/')[-1])

edited Aug 6, 2018 at 17:41

sshah98

3624 silver badges16 bronze badges

answered Aug 6, 2018 at 17:32

Kenan

14.2k9 gold badges47 silver badges56 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Replace part of string with a different column's value pandas + python

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related