Argument Number Issue in time_strech()

Question

When I define my stretch() function like this:

def stretch(data, rate=0.8):
    return librosa.effects.time_stretch(data, rate)

It gives the error:

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
Cell In[56], line 6
      4 y = []
      5 for i in range(len(audio_df)):
----> 6     feature=get_features(audio_df['Arrays'].iloc[i]);
      7     for j in feature:
      8         x.append(j) 

Cell In[55], line 14, in get_features(data)
     11 result.append(res2)
     13 # with stretching and pitching
---> 14 new_data = stretch(data)
     15 data_stretch_pitch = pitch(new_data, sr)
     16 res3 = extract_features(data_stretch_pitch)

Cell In[53], line 7, in stretch(data, rate)
      6 def stretch(data, rate=0.8):
----> 7     return librosa.effects.time_stretch(data, rate)

TypeError: time_stretch() takes 1 positional argument but 2 were given

But when I remove the 'rate' argument, it gives the error:

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
Cell In[58], line 6
      4 y = []
      5 for i in range(len(audio_df)):
----> 6     feature=get_features(audio_df['Arrays'].iloc[i]);
      7     for j in feature:
      8         x.append(j) 

Cell In[55], line 14, in get_features(data)
     11 result.append(res2)
     13 # with stretching and pitching
---> 14 new_data = stretch(data)
     15 data_stretch_pitch = pitch(new_data, sr)
     16 res3 = extract_features(data_stretch_pitch)

Cell In[57], line 7, in stretch(data, rate)
      6 def stretch(data, rate=0.8):
----> 7     return librosa.effects.time_stretch(data)

TypeError: time_stretch() missing 1 required keyword-only argument: 'rate'

I removed the 'rate' parameter to try working with the default that (even though that would have any effect on the data), but it still gave the error. I might be wrong, but according to me, when I give 2 arguments, it says it needs only 1, when I give 1, it says I'm missing one argument, what should I do?

Answer 1

The time_stretch() function from the librosa library requires the rate parameter as a keyword-only argument. You need to provide the rate parameter explicitly as a keyword argument when calling the function :

def stretch(data, rate=0.8):
    return librosa.effects.time_stretch(data, rate=rate)