如何将日期的特定格式转换为 Python Pandas 中有用且可读的日期格式？

Question

I have DataFrame in Pandas like below:

DATA TYPES:

• ID - numeric

• HOLIDAY - object

• YEAR - object

  ID	HOLIDAY	YEAR
  111	1 sty	2022
  222	20 kwi	2022
  333	8 mar	2022
  ...	...	...

• sty - January

• kwi - APril

• mar - March

And I need to convert above table so as to have full and useful date (as string format).

So, I need to have something like below:

ID  | HOLIDAY     | YEAR
----|-------------|-------
111 | 01-01-2022  | 2022
222 | 20-02-2022  | 2022
333 | 08-03-2022  | 2022
... | ...         | ...

How can I do that in Python Pandas?

I used somethink like that:

df['HOLIDAY'] = pd.to_datetime(df['HOLIDAY'] +" "+ df['YEAR'] , format='%d %b %Y')
df['HOLIDAY'] = df['HOLIDAY'].dt.strftime('%d-%m-%Y')

but it generate error like the follow: ValueError: time data '1 sty 2022' does not match format '%d %b %Y' (match)

Answer 1

hello you can use this:

d={'sty':'-1','kwi':'-4','mar':'-3'} #creat dict 

a=df.HOLIDAY.tolist() # creat list of original holiday
for i in range(len(df)):
    for word, replacement in d.items():
        a[i] = a[i].replace(word, replacement)# creat a loop that replace the mount by her number
        a[i] = a[i].replace(" ", "")# delete the space ex '1 sty' -> '1sty'
df.HOLIDAY=a
l=[]
for i in range(len(df)):
    l.append(str(df.HOLIDAY[i])+'-'+str(df.YEAR[i]))#loop that concatenat year and holiday

df.HOLIDAY=l# replace holiday in df by new values

df.HOLIDAY=pd.to_datetime(df.HOLIDAY, format="%d-%m-%Y")#transform holiday from str to datetime 

Answer 2

Try:

df["HOLIDAY"] = df["HOLIDAY"].apply(
    lambda x: x.replace("sty", "January")
    .replace("kwi", "April")
    .replace("mar", "March")
)

df["HOLIDAY"] = pd.to_datetime(
    df["HOLIDAY"] + " " + df["YEAR"].astype(str)
).dt.strftime("%d-%m-%Y")

print(df)

Prints:

    ID     HOLIDAY  YEAR
0  111  01-01-2022  2022
1  222  20-04-2022  2022
2  333  08-03-2022  2022