pandas 常用清洗数据（一）

Look at the some basic stats for the ‘imdb_score’ column: data.imdb_score.describe()
Select a column: data[‘movie_title’]
Select the first 10 rows of a column: data[‘duration’][:10]
Select multiple columns: data[[‘budget’,’gross’]]
Select all movies over two hours long: data[data[‘duration’] > 120]

data.country = data.country.fillna(‘’)
data.duration = data.duration.fillna(data.duration.mean())

data = pd.read_csv(‘movie_metadata.csv’, dtype={title_year: str})

data[‘movie_title’].str.upper()

Similarly, to get rid of trailing whitespace:

data[‘movie_title’].str.strip()

data = data.rename(columns = {‘title_year’:’release_date’, ‘movie_facebook_likes’:’facebook_likes’})

丢弃带有NAN的所有项
data.dropna()

丢弃所有元素都是NAN的行
data.dropna(how=‘all‘)

丢弃所有元素都是NAN的列
data.dropna(axis=1,how=‘all‘)  #axis = 0 行，=1 列

只保留至少有3个非NAN值的行
data.dropna(thresh=3)