Removing file extension by using rstrip in numpy

Question

Suppose that I have a list of song names

songlist = np.array(['1.mp3', '2.mp3','3.mp3'])

According to numpy documentation, there's a useful char function called rstrip :

For each element in self, return a copy with the trailing characters removed.

Since the file extension is exactly located in the trailing of the string, so I try using this rstrip to remove the file extensions

np.core.char.rstrip(songlist,'.mp3')

However, it gives me this following output

array(['1', '2', ''], dtype='

What am I doing wrong here? How to use the rstrip function to remove the file extensions correctly?

Answer 1

I think numpy is not the best tool for working with strings. I'd use native python, personally.

songlist = np.array(['1.mp3', '2.mp3','3.mp3'])

# extract the part you want with split()
songlist = [s.split('.')[0] for s in songlist]
# could also just slice
# songlist = [s[:-4] for s in songlist]

Answer 2

If you want to use numpy string functions:

s = np.array([np.str.rpartition(s,'.mp3')[0] for s in songlist])

You could also look at partition and replace

Answer 3

As @dgumo mentioned, rstrip removes characters irrespective of their order. To remove ".mp3" only,

[song.replace('.mp3' , '') for song in songlist]

Or if you are sure the string ends with .mp3

[song[:-4] if song.endswith('.mp3') else song for song in songlist]