Reputation: 885
Hy,
I'm new in Spark and I'm trying using ML recommendation.
My Code
df = sqlContext.createDataFrame(
[(0, 0, 4.0), (0, 1, 2.0), (1, 1, 3.0), (1, 2, 4.0), (2, 1, 1.0), (2, 2, 5.0)],
["user", "item", "rating"])
als = ALS(rank=10, maxIter=5)
model = als.fit(df)
model.userFactors.orderBy("id").collect()
How can I obtain 2 recommendation for all users for all movies?
thanks for you time.
Upvotes: 4
Views: 1060
Reputation: 330073
It is not directly possible with ml.recommendation.ALSModel
. You could use transform
method
users = df.select("user").distinct()
items = df.select("item").distinct()
model.transform(users.join(items))
and filter the results afterwards but it is extremely inefficient. As far as I can tell it would be better to simply use mllib.recommendation.ALS
here:
from pyspark.mllib.recommendation import ALS, Rating
model = ALS.train(df.rdd.map(lambda r: Rating(*r)), 10, 5)
model.recommendProductsForUsers(2)
Upvotes: 5