Remove leading zeros or foreign characters in sequence number

Question

Eg: In the below column "Sample", I need to remove columns 2, 3 & 5 because they either have a leading zero in the beginning or a special character at the start.

Index	Sample
1	12345
2	00152
3	09
4	325
5	.1246

I tried changing the "Sample" column datatype to string and extracting the first character like this:

t = df['Sample'].astype(str).str[0].astype(int)

But it gives me this output:

print(t)

 
|   1   |  1  | 
|   2   |  1  | 
|   3   |  9  | 
|   4   |  3  |
|   5   |  0  | 

It want it like this so that I can remove the respective rows using the index value:

 
|   1   |  1  | 
|   2   |  0  | 
|   3   |  0  | 
|   4   |  3  |
|   5   |  .  | 

Is my approach correct? Can anyone please help me regarding this? Thank a lot.

Answer 1

You may try using str.match as follows:

df = df[df["sample"].str.match(r'[1-9]')]

This would only retain rows having sample values starting with a digit, other than zero.