Replace string while considering the last character (number) value-CodePudding

I am starting with Python. I need to replace the strings from 'Old' column basis on a condition. If the first character of the string is A I need to replace it with Z, but I also need to add 1 to value of the last character

For example:

Old	New
A2	Z3
C4	C4
B4	B4
A5	Z6
A1	Z2

df = pd.DataFrame({'Old': ['A2', 'C4', 'B4', 'A5'], 'New': ['Z3', 'C4', 'B4', 'Z6']})
df['New'] = df['Old'].str.replace('A','Z')

CodePudding user response：

Use a custom function:

df['New'] = df['Old'].apply(lambda x: x if x[0] != 'A' else f'Z{int(x[1:]) 1}')
print(df)

# Output:
  Old New
0  A2  Z3
1  C4  C4
2  B4  B4
3  A5  Z6