Andere joins

Data samenvoegen met pandas

Aaren Stubberfield

Instructor

Right join

Venn-diagram right join

Right join

Afbeelding van twee tabellen gemerged met een right join

Data bekijken

movie_to_genres = pd.read_csv('tmdb_movie_to_genres.csv')
tv_genre = movie_to_genres[movie_to_genres['genre'] == 'TV Movie']
print(tv_genre)

       movie_id  genre
4998   10947     TV Movie
5994   13187     TV Movie
7443   22488     TV Movie
10061  78814     TV Movie
10790  153397    TV Movie
10835  158150    TV Movie
11096  205321    TV Movie
11282  231617    TV Movie

Data filteren

m = movie_to_genres['genre'] == 'TV Movie'
tv_genre = movie_to_genres[m]
print(tv_genre)

       movie_id  genre
4998   10947     TV Movie
5994   13187     TV Movie
7443   22488     TV Movie
10061  78814     TV Movie
10790  153397    TV Movie
10835  158150    TV Movie
11096  205321    TV Movie
11282  231617    TV Movie

Data om te mergen

  id     title            popularity       release_date
0 257    Oliver Twist     20.415572        2005-09-23  
1 14290  Better Luck ...  3.877036         2002-01-12  
2 38365  Grown Ups        38.864027        2010-06-24  
3 9672   Infamous         3.6808959999...  2006-11-16  
4 12819  Alpha and Omega  12.300789        2010-09-17

       movie_id  genre
4998   10947     TV Movie
5994   13187     TV Movie
7443   22488     TV Movie
10061  78814     TV Movie
10790  153397    TV Movie

Mergen met right join

tv_movies = movies.merge(tv_genre, how='right', 
                         left_on='id', right_on='movie_id')
print(tv_movies.head())

  id      title            popularity  release_date  movie_id  genre   
0 153397  Restless         0.812776    2012-12-07    153397    TV Movie
1 10947   High School ...  16.536374   2006-01-20    10947     TV Movie
2 231617  Signed, Seal...  1.444476    2013-10-13    231617    TV Movie
3 78814   We Have Your...  0.102003    2011-11-12    78814     TV Movie
4 158150  How to Fall ...  1.923514    2012-07-21    158150    TV Movie

Outer join

Venn-diagram full outer join

Outer join

Afbeelding van twee tabellen gemerged met een right join

Datasets voor outer join

m = movie_to_genres['genre'] == 'Family'
family = movie_to_genres[m].head(3)

  movie_id  genre 
0 12        Family
1 35        Family
2 105       Family

m = movie_to_genres['genre'] == 'Comedy'
comedy = movie_to_genres[m].head(3)

  movie_id  genre 
0 5         Comedy
1 13        Comedy
2 35        Comedy

Mergen met outer join

family_comedy = family.merge(comedy, on='movie_id', how='outer', 
                             suffixes=('_fam', '_com'))
print(family_comedy)

  movie_id  genre_fam  genre_com
0 12        Family     NaN      
1 35        Family     Comedy   
2 105       Family     NaN      
3 5         NaN        Comedy   
4 13        NaN        Comedy

Laten we oefenen!

Data samenvoegen met pandas