Thanks for your help Akhil, however, this is creating an output folder and storing the result sets in multiple files. Also the record count in the result set seems to have multiplied!! Is there any other way to achieve this?
Thanks!! Regards, Saurabh Agrawal Vice President Markit Green Boulevard B-9A, Tower C 3rd Floor, Sector - 62, Noida 201301, India +91 120 611 8274 Office From: Akhil Das [mailto:ak...@sigmoidanalytics.com] Sent: Monday, November 24, 2014 5:55 PM To: Saurabh Agrawal Cc: user@spark.apache.org Subject: Re: Writing collection to file error Hi Saurabh, Here your ratesAndPreds is a RDD of type [((int, int), (Double, Double))] not an Array. Now, if you want to save it on disk, then you can simply call the saveAsTextFile and provide the location. So change your last line from this: ratesAndPreds.foreach(pw.println) to this ratesAndPreds.saveAsTextFile("/path/CFOutput") Thanks Best Regards On Mon, Nov 24, 2014 at 5:05 PM, Saurabh Agrawal <saurabh.agra...@markit.com<mailto:saurabh.agra...@markit.com>> wrote: import org.apache.spark.mllib.recommendation.ALS import org.apache.spark.mllib.recommendation.Rating // Load and parse the data val data = sc.textFile("/path/CFReady.txt") val ratings = data.map(_.split('\t') match { case Array(user, item, rate) => Rating(user.toInt, item.toInt, rate.toDouble) }) // Build the recommendation model using ALS val rank = 50 val numIterations = 100 val model = ALS.train(ratings, rank, numIterations, 0.10) // 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) val pw = new PrintWriter(new File("/path/CFOutput.txt")) ratesAndPreds.foreach(pw.println) } Hi, Consider the highlighted code, I am trying to write the output of ratesAndPreds array on to the disk. But I get error Task not serializable at org.apache.spark.util.ClosureCleaner$.ensureSerializable(ClosureCleaner.scala:166) at org.apache.spark.util.ClosureCleaner$.clean(ClosureCleaner.scala:158) at org.apache.spark.SparkContext.clean(SparkContext.scala:1242) at org.apache.spark.rdd.RDD.foreach(RDD.scala:758) at $iwC$$iwC$$iwC$$iwC$$iwC$$iwC.<init>(<console>:36) at $iwC$$iwC$$iwC$$iwC$$iwC.<init>(<console>:41) at $iwC$$iwC$$iwC$$iwC.<init>(<console>:43) at $iwC$$iwC$$iwC.<init>(<console>:45) at $iwC$$iwC.<init>(<console>:47) at $iwC.<init>(<console>:49) at <init>(<console>:51) at .<init>(<console>:55) at .<clinit>(<console>) at .<init>(<console>:7) at .<clinit>(<console>) at $print(<console>) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.apache.spark.repl.SparkIMain$ReadEvalPrint.call(SparkIMain.scala:789) at org.apache.spark.repl.SparkIMain$Request.loadAndRun(SparkIMain.scala:1062) at org.apache.spark.repl.SparkIMain.loadAndRunReq$1(SparkIMain.scala:615) at org.apache.spark.repl.SparkIMain.interpret(SparkIMain.scala:646) at org.apache.spark.repl.SparkIMain.interpret(SparkIMain.scala:610) at org.apache.spark.repl.SparkILoop.reallyInterpret$1(SparkILoop.scala:814) at org.apache.spark.repl.SparkILoop.interpretStartingWith(SparkILoop.scala:859) at org.apache.spark.repl.SparkILoop.command(SparkILoop.scala:771) at org.apache.spark.repl.SparkILoop.processLine$1(SparkILoop.scala:616) at org.apache.spark.repl.SparkILoop.innerLoop$1(SparkILoop.scala:624) at org.apache.spark.repl.SparkILoop.loop(SparkILoop.scala:629) at org.apache.spark.repl.SparkILoop$$anonfun$process$1.apply$mcZ$sp(SparkILoop.scala:954) at org.apache.spark.repl.SparkILoop$$anonfun$process$1.apply(SparkILoop.scala:902) at org.apache.spark.repl.SparkILoop$$anonfun$process$1.apply(SparkILoop.scala:902) at scala.tools.nsc.util.ScalaClassLoader$.savingContextLoader(ScalaClassLoader.scala:135) at org.apache.spark.repl.SparkILoop.process(SparkILoop.scala:902) at org.apache.spark.repl.SparkILoop.process(SparkILoop.scala:997) at org.apache.spark.repl.Main$.main(Main.scala:31) at org.apache.spark.repl.Main.main(Main.scala) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.apache.spark.deploy.SparkSubmit$.launch(SparkSubmit.scala:328) at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:75) at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala) Caused by: java.io.NotSerializableException: java.io.PrintWriter at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1183) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347) at org.apache.spark.serializer.JavaSerializationStream.writeObject(JavaSerializer.scala:42) at org.apache.spark.serializer.JavaSerializerInstance.serialize(JavaSerializer.scala:73) at org.apache.spark.util.ClosureCleaner$.ensureSerializable(ClosureCleaner.scala:164) ... 45 more I am very new to Spark and Scala, can somebody please guide me here? Thanks, Saurabh ________________________________ This e-mail, including accompanying communications and attachments, is strictly confidential and only for the intended recipient. Any retention, use or disclosure not expressly authorised by Markit is prohibited. This email is subject to all waivers and other terms at the following link: http://www.markit.com/en/about/legal/email-disclaimer.page Please visit http://www.markit.com/en/about/contact/contact-us.page? for contact information on our offices worldwide. MarkitSERV Limited has its registered office located at Level 4, Ropemaker Place, 25 Ropemaker Street, London, EC2Y 9LY and is authorized and regulated by the Financial Conduct Authority with registration number 207294 ________________________________ This e-mail, including accompanying communications and attachments, is strictly confidential and only for the intended recipient. Any retention, use or disclosure not expressly authorised by Markit is prohibited. This email is subject to all waivers and other terms at the following link: http://www.markit.com/en/about/legal/email-disclaimer.page Please visit http://www.markit.com/en/about/contact/contact-us.page? for contact information on our offices worldwide. MarkitSERV Limited has its registered office located at Level 4, Ropemaker Place, 25 Ropemaker Street, London, EC2Y 9LY and is authorized and regulated by the Financial Conduct Authority with registration number 207294
