How can I count empty cell in .csv file? if row['PredictionString']== “ ”

Question

I have a .csv file with some empty cells. How can I count empty cells in .csv file? if row['PredictionString']== " " ?

    submission = pd.read_csv(os.path.join(ROOT_DIR, 'submission.csv'))

    for index, row in submission.iterrows():
        if row['PredictionString']== " ": 
            counter1 = counter1 + 1

    print('output:', counter1)

It doesn't work.

output: 0

First col name: patientId

Second col name: PredictionString

.csv_printscreen

Answer 1

If submission is a pandas dataframe (like it seems to be), you can count like this:

counter1 = len(submission[submission.PredictionString == ' '])

Without any for loops.

EDIT: Considering as empty ' ' , '' and NaN 's:

counter1 = len(submission[(submission.PredictionString == ' ') | (submission.PredictionString == '') | (submission.PredictionString.isnull())])

Example:

>> mydict = {'patientId': {0: '1', 1: '1', 2: '1'},
>>           'PredictionString': {0: '', 1: ' ', 2: np.NaN}}
>> submission = pd.DataFrame(mydict)
>> counter1 = len(submission[(submission.PredictionString == ' ') | (submission.PredictionString == '') | (submission.PredictionString.isnull())])
>> print(counter1)
3