iPython：如何计算字符串在单元格中出现的次数？

Question

I have a data frame with the columns Movie Title and Cast that looks like this:

Column 1 has the name of the movie, whilst Column 2 lists the full cast of the film. The cast has been taken from the site TMDB.

Column 2 has the pattern: 'cast_id': {cast_id_number} , 'character': {character_name} , 'credit_id': {credit_number} , 'gender': {gender_identifier} , etc.

I am writing a project for school looking at the gender split in different films. I therefore want to create a column that counts the number of male/female actors in a specific film. eg:

Movie Title | Cast | No. of Males | No. of Females
Toy Story   | .... | 3            | 7

However, I'm not sure how to go about doing this. I've tried using str.count but it keeps returning all values as 0, even if I can see a cell contains 'gender': 2 or 'gender': 1 .

I'm assuming it may need an if loop counter that reads the string in each row and adds 1 every time it encounters 'gender': 2 but have no idea how to implement this.

Answer 1

You will need to iterate over each cast member for each movie and determine how many cast members are female/male. Something like this should work:

def gender_ct(data, gender=1):
    return len([1 for x in data if x['gender'] == gender])

df['No. of Females'] = df['Cast'].apply(gender_ct, gender=1)
df['No. of Males'] = df['Cast'].apply(gender_ct, gender=2)