[SPARK-11548][DOCS] Replaced example code in mllib-collaborative-filtering.md using include_example

Kindly review the changes.

Author: Rishabh Bhardwaj <rbnext29@gmail.com>

Closes #9519 from rishabhbhardwaj/SPARK-11337.

1 files changed, 3 insertions, 135 deletions

diff --git a/docs/mllib-collaborative-filtering.md b/docs/mllib-collaborative-filtering.md
index 1ad52123c7..7cd1b894e7 100644
--- a/docs/mllib-collaborative-filtering.md
+++ b/docs/mllib-collaborative-filtering.md
@@ -66,43 +66,7 @@ recommendation model by measuring the Mean Squared Error of rating prediction.
 
 Refer to the [`ALS` Scala docs](api/scala/index.html#org.apache.spark.mllib.recommendation.ALS) for details on the API.
 
-{% highlight scala %}
-import org.apache.spark.mllib.recommendation.ALS
-import org.apache.spark.mllib.recommendation.MatrixFactorizationModel
-import org.apache.spark.mllib.recommendation.Rating
-
-// Load and parse the data
-val data = sc.textFile("data/mllib/als/test.data")
-val ratings = data.map(_.split(',') match { case Array(user, item, rate) =>
-    Rating(user.toInt, item.toInt, rate.toDouble)
-  })
-
-// Build the recommendation model using ALS
-val rank = 10
-val numIterations = 10
-val model = ALS.train(ratings, rank, numIterations, 0.01)
-
-// Evaluate the model on rating data
-val usersProducts = ratings.map { case Rating(user, product, rate) =>
-  (user, product)
-}
-val predictions = 
-  model.predict(usersProducts).map { case Rating(user, product, rate) => 
-    ((user, product), rate)
-  }
-val ratesAndPreds = ratings.map { case Rating(user, product, rate) => 
-  ((user, product), rate)
-}.join(predictions)
-val MSE = ratesAndPreds.map { case ((user, product), (r1, r2)) => 
-  val err = (r1 - r2)
-  err * err
-}.mean()
-println("Mean Squared Error = " + MSE)
-
-// Save and load model
-model.save(sc, "myModelPath")
-val sameModel = MatrixFactorizationModel.load(sc, "myModelPath")
-{% endhighlight %}
+{% include_example scala/org/apache/spark/examples/mllib/RecommendationExample.scala %}
 
 If the rating matrix is derived from another source of information (e.g., it is inferred from
 other signals), you can use the `trainImplicit` method to get better results.
@@ -123,81 +87,7 @@ that is equivalent to the provided example in Scala is given below:
 
 Refer to the [`ALS` Java docs](api/java/org/apache/spark/mllib/recommendation/ALS.html) for details on the API.
 
-{% highlight java %}
-import scala.Tuple2;
-
-import org.apache.spark.api.java.*;
-import org.apache.spark.api.java.function.Function;
-import org.apache.spark.mllib.recommendation.ALS;
-import org.apache.spark.mllib.recommendation.MatrixFactorizationModel;
-import org.apache.spark.mllib.recommendation.Rating;
-import org.apache.spark.SparkConf;
-
-public class CollaborativeFiltering {
-  public static void main(String[] args) {
-    SparkConf conf = new SparkConf().setAppName("Collaborative Filtering Example");
-    JavaSparkContext sc = new JavaSparkContext(conf);
-
-    // Load and parse the data
-    String path = "data/mllib/als/test.data";
-    JavaRDD<String> data = sc.textFile(path);
-    JavaRDD<Rating> ratings = data.map(
-      new Function<String, Rating>() {
-        public Rating call(String s) {
-          String[] sarray = s.split(",");
-          return new Rating(Integer.parseInt(sarray[0]), Integer.parseInt(sarray[1]), 
-                            Double.parseDouble(sarray[2]));
-        }
-      }
-    );
-
-    // Build the recommendation model using ALS
-    int rank = 10;
-    int numIterations = 10;
-    MatrixFactorizationModel model = ALS.train(JavaRDD.toRDD(ratings), rank, numIterations, 0.01); 
-
-    // Evaluate the model on rating data
-    JavaRDD<Tuple2<Object, Object>> userProducts = ratings.map(
-      new Function<Rating, Tuple2<Object, Object>>() {
-        public Tuple2<Object, Object> call(Rating r) {
-          return new Tuple2<Object, Object>(r.user(), r.product());
-        }
-      }
-    );
-    JavaPairRDD<Tuple2<Integer, Integer>, Double> predictions = JavaPairRDD.fromJavaRDD(
-      model.predict(JavaRDD.toRDD(userProducts)).toJavaRDD().map(
-        new Function<Rating, Tuple2<Tuple2<Integer, Integer>, Double>>() {
-          public Tuple2<Tuple2<Integer, Integer>, Double> call(Rating r){
-            return new Tuple2<Tuple2<Integer, Integer>, Double>(
-              new Tuple2<Integer, Integer>(r.user(), r.product()), r.rating());
-          }
-        }
-    ));
-    JavaRDD<Tuple2<Double, Double>> ratesAndPreds = 
-      JavaPairRDD.fromJavaRDD(ratings.map(
-        new Function<Rating, Tuple2<Tuple2<Integer, Integer>, Double>>() {
-          public Tuple2<Tuple2<Integer, Integer>, Double> call(Rating r){
-            return new Tuple2<Tuple2<Integer, Integer>, Double>(
-              new Tuple2<Integer, Integer>(r.user(), r.product()), r.rating());
-          }
-        }
-    )).join(predictions).values();
-    double MSE = JavaDoubleRDD.fromRDD(ratesAndPreds.map(
-      new Function<Tuple2<Double, Double>, Object>() {
-        public Object call(Tuple2<Double, Double> pair) {
-          Double err = pair._1() - pair._2();
-          return err * err;
-        }
-      }
-    ).rdd()).mean();
-    System.out.println("Mean Squared Error = " + MSE);
-
-    // Save and load model
-    model.save(sc.sc(), "myModelPath");
-    MatrixFactorizationModel sameModel = MatrixFactorizationModel.load(sc.sc(), "myModelPath");
-  }
-}
-{% endhighlight %}
+{% include_example java/org/apache/spark/examples/mllib/JavaRecommendationExample.java %}
 </div>
 
 <div data-lang="python" markdown="1">
@@ -207,29 +97,7 @@ recommendation by measuring the Mean Squared Error of rating prediction.
 
 Refer to the [`ALS` Python docs](api/python/pyspark.mllib.html#pyspark.mllib.recommendation.ALS) for more details on the API.
 
-{% highlight python %}
-from pyspark.mllib.recommendation import ALS, MatrixFactorizationModel, Rating
-
-# Load and parse the data
-data = sc.textFile("data/mllib/als/test.data")
-ratings = data.map(lambda l: l.split(',')).map(lambda l: Rating(int(l[0]), int(l[1]), float(l[2])))
-
-# Build the recommendation model using Alternating Least Squares
-rank = 10
-numIterations = 10
-model = ALS.train(ratings, rank, numIterations)
-
-# Evaluate the model on training data
-testdata = ratings.map(lambda p: (p[0], p[1]))
-predictions = model.predictAll(testdata).map(lambda r: ((r[0], r[1]), r[2]))
-ratesAndPreds = ratings.map(lambda r: ((r[0], r[1]), r[2])).join(predictions)
-MSE = ratesAndPreds.map(lambda r: (r[1][0] - r[1][1])**2).mean()
-print("Mean Squared Error = " + str(MSE))
-
-# Save and load model
-model.save(sc, "myModelPath")
-sameModel = MatrixFactorizationModel.load(sc, "myModelPath")
-{% endhighlight %}
+{% include_example python/mllib/recommendation_example.py %}
 
 If the rating matrix is derived from other source of information (i.e., it is inferred from other
 signals), you can use the trainImplicit method to get better results.