Python Regular Expression (RegEx). Extract Dates from Strings in Pandas DataFrame

This video explain how to extract dates (or timestamps) with specific format from a Pandas dataframe.

Used Python modules:

The content of video is:
Step 1: Load the data (0:18)
Step 2: Make extra columns for Date (1:55)
Step 3: Set indexes for columns (2:34)
Step 4: Define the Regular Expression Pattern in Date Format (4:00)
Step 5: Looking for Date values in DataFrame. Explaining group() method in this example (6:15)
Step 6: Re-arrange columns in DataFrame (Final: 9:15).

Hoping this tutorial remids basics of Pandas functions and helps for data analyst and data scientist despite the field the business they are doing in.

Vytautas

[amangautam]

one of the best explanation!! kudos to u!!

[basicmaths]

very helpful, my lead data scientist was not helping me, finally i got this video after so much searching, and i was working for an assignment for change the company. while doing assignment, i got the idea of appending into rows of particular column that i was stuck in my current company. thanks a lot!! please make a video on json file, converting unstructured data to structured. and you are using jupyter notebook that is so awesome to understand unlike other videos .

[dipsikhaphukan]

I want to extract some information in structured format by reading a doctor's prescription. Information such as medicine name, time for taking those medicine and the quantity, etc. Can you please help?

[DataScienceGarage]

If you found any useful in this video I reccomend to check another one in pararell.

[kkarthikkumar]

Can anyone help me out. I just need to find the position of a date format ( 05/02/2020 or Nov 5 2004 ) in a string in python language.
Please let me know if you get answer.

[erenhan]

this is great, thanks for explaanation

[amangautam]

after executing the code it shows me this error when I type group() for date line: 'NoneType' object has no attribute 'group', but the code is running without error when using without group, idk how to solve this

[cordularaecke]

Sorry, assumed description column would be the 'index', revised solution;


data = {
'description': [
'made payment on 04/11/2019', 'Meeting with clients (07/06/2014)',
'Christmas party will take place on 20/12/2018',
'Valentine day is on 14/02/2018 this year',
'Easter was in 21/04/2018 this year',
'17/06/2019 was a hot day in Lithuania',
'My birthday is on 28/05/2019, not quite long ago'
],
'values': [2000, 0, 1400, 140, 740, 20, 175]
}

df = pd.DataFrame(data)
df.insert(0, 'date', df.description.str.extract(r'(\d{2}\/\d{2}\/\d{4})', expand=False))
df

[sriramcharankola]

What if there are multiple regex patterns? Can someone write it here?

[azharshaikh]

Thanks. It really helped. But if we want to fetch the date for eg. (December 31, 2009). How can we write the regex code for it. Pls help.

[erick]

Good explanation, but you are iterating the most inefficient way you can iterate through a dataframe. Use better series.str.find, or even a dataframe.apply would be better

[yuzhiyan]

Thank you so much for the video. everything else works perfectly for me except .group() part. I kept getting this message "AttributeError: 'NoneType' object has no attribute 'group'". Any suggestions on this issue?

[yadunandanacharya]

"No.3/B, 8th Main, Nandhini Layout, Bangalore - 560096, Near Mahalakshmi Layout"
Can I extract Pincode and Area name like "Nandhini Layout" from the Address column
above using Pandas and "re" Library as you have shown above Sir?
And please tell me how?

[LuizPerciliano_]

my friend, my dataframe has rows that will not be filled, for example, not all rows have a date, so the column will be "Empty", however, when using "group ()" it has the following error - AttributeError: 'NoneType' object has no attribute 'group'.
However, it records on other lines with the search information.
Do you know how to treat it? Thank you for the excellent class.

[LuizPerciliano_]

show this video, thanks my dear friend

[KuftuKa]

Could you do a video on how to do the same but with lambda expressions?

[and_and]

Hello, I have this mistake "RecursionError: maximum recursion depth exceeded" How can I solve this?

[whatistrending]

The code ran into error. It says AttributeError: 'str' object has no attribute 'iat'

[varshadevgankar]

hi!
i want a function in python that identify which column have date in them?
please help me out in this..

[georgesmith]

Maybe you could also convert them to datetime in order to do some sorting