[FIXED] Calculate the sum of the numbers separated by a comma in a dataframe column

Issue

I am trying to calculate the sum of all the numbers separated by a comma in a dataframe column however I keep getting error. This is what the dataframe looks like:

Description  scores
logo    
graphics    
eyewear      0.360740,-0.000758
glasses      0.360740,-0.000758
picture      -0.000646
tutorial     0.001007,0.000968,0.000929,0.000889 
computer     0.852264  0.001007,0.000968,0.000929,0.000889

This is what the code looks like

test['Sum'] = test['scores'].apply(lambda x: sum(map(float, x.split(','))))

However I keep getting the following error

ValueError: could not convert string to float:

I though it could it be because of missing values at the start of the dataframe. But I subset the dataframe to exclude the missing the values, still I get the same error.

Output

Description  scores                                               SUM
logo    
graphics    
eyewear      0.360740,-0.000758                                0.359982
glasses      0.360740,-0.000758                                0.359982
picture      -0.000646                                        -0.000646
tutorial     0.001007,0.000968,0.000929,0.000889               0.003793
computer     0.852264  0.001007,0.000968,0.000929,0.000889     0.856057 

How can I resolve it?

Solution

There are times when using Python seems to be very effective, this might be one of those.

df['scores'].apply(lambda x: sum(float(i) if len(x) > 0 else np.nan for i in x.split(',')))

0         NaN
1         NaN
2    0.359982
3    0.359982
4   -0.000646
5    0.003793
6    0.856057

Answered By - Vaishali