标签:scala 获得 for list 分时 top apache rdd 打印
第一次写博客,新人上路,欢迎大家多多指教!!!
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现有如此三份数据:
1、users.dat 数据格式为: 2::M::56::16::70072
对应字段为:UserID BigInt, Gender String, Age Int, Occupation String, Zipcode String
对应字段中文解释:用户 id,性别,年龄,职业,邮政编码
2、movies.dat 数据格式为: 2::Jumanji (1995)::Adventure|Children‘s|Fantasy
对应字段为:MovieID BigInt, Title String, Genres String
对应字段中文解释:电影 ID,电影名字,电影类型
3、ratings.dat 数据格式为: 1::1193::5::978300760
对应字段为:UserID BigInt, MovieID BigInt, Rating Double, Timestamped String
对应字段中文解释:用户 ID,电影 ID,评分,评分时间戳
需求:
1、求被评分次数最多的 10 部电影,并给出评分次数(电影名,评分次数)
2、分别求男性,女性当中评分最高的 10 部电影(性别,电影名,影评分)
3、分别求男性,女性看过最多的 10 部电影(性别,电影名)
4、年龄段在“18-24”的男人,最喜欢看 10 部电影
5、求 movieid = 2116 这部电影各年龄段(因为年龄就只有 7 个,就按这个 7 个分就好了)
的平均影评(年龄段,影评分)
6、求最喜欢看电影(影评次数最多)的那位女性评最高分的 10 部电影的平均影评分(观影
者,电影名,影评分)
7、求好片(评分>=4.0)最多的那个年份的最好看的 10 部电影
8、求 1997 年上映的电影中,评分最高的 10 部 Comedy 类电影
9、该影评库中各种类型电影中评价最高的 5 部电影(类型,电影名,平均影评分)
10、各年评分最高的电影类型(年份,类型,影评分)
先建立一个Utils类,主要用于初始化配置信息以及解析原始数据
package movie_rating import org.apache.spark.rdd.RDD import org.apache.spark.{SparkConf, SparkContext} object Utils { //初始化SparkConf对象 private[movie_rating] val conf = new SparkConf().setAppName("FileReview").setMaster("local") //初始化sc对象 private[movie_rating] val sc = new SparkContext(conf) sc.setLogLevel("ERROR") //读取hdfs上的数据 private[movie_rating] val movie = sc.textFile("hdfs://myha01/mydata/film_review/movies.dat") private[movie_rating] val ratings = sc.textFile("hdfs://myha01/mydata/film_review/ratings.dat") private[movie_rating] val users = sc.textFile("hdfs://myha01/mydata/film_review/users.dat") //将原始数据转为RDD格式 private[movie_rating] val movieRdd: RDD[(String, String, String)] = movie.map(_.split("::")).map(m => (m(0), m(1), m(2))) private[movie_rating] val ratingsRdd: RDD[(String, String, String, String)] = ratings.map(_.split("::")).map(r => (r(0), r(1), r(2), r(3))) private[movie_rating] val usersRdd: RDD[(String, String, String, String, String)] = users.map(_.split("::")).map(u => (u(0), u(1), u(2), u(3), u(4))) }
第一问:
package movie_rating import org.apache.spark.rdd.RDD /** * Utils.usersRdd:对应字段中文解释:用户 id,性别,年龄,职业,邮政编码 * Utils.movieRdd:对应字段中文解释:电影 ID,电影名字,电影类型 * Utils.ratingsRdd:对应字段中文解释:用户 ID,电影 ID,评分,评分时间戳 */ object Demand01 { /** * 1、求被评分次数最多的 10 部电影,并给出评分次数(电影名,评分次数) */ def main(args: Array[String]): Unit = { //获取电影id与对应的评分次数 val movieID_rating: RDD[(String, Int)] = Utils.ratingsRdd.map(x => (x._2, 1)) val movieID_times: RDD[(String, Int)] = movieID_rating.reduceByKey(_ + _).sortBy(_._2, false) //获得电影id和电影名 val movieID_name: RDD[(String, String)] = Utils.movieRdd.map(x => (x._1, x._2)) //关联movieID_times和movieID_name,获得电影id,电影名,评分次数 val result: RDD[(String, Int)] = movieID_times.join(movieID_name).sortBy(_._2._1, false).map(x => (x._2._2, x._2._1)) //输出结果 result.take(10).foreach(println(_)) } }
第二问
package movie_rating import org.apache.spark.rdd.RDD /** * Utils.usersRdd:对应字段中文解释:用户 id,性别,年龄,职业,邮政编码 * Utils.movieRdd:对应字段中文解释:电影 ID,电影名字,电影类型 * Utils.ratingsRdd:对应字段中文解释:用户 ID,电影 ID,评分,评分时间戳 */ object Demand02 { /** * 2、分别求男性,女性当中评分最高的 10 部电影(性别,电影名,影评分) */ def main(args: Array[String]): Unit = { //(userID, sex) val userID_sex: RDD[(String, String)] = Utils.usersRdd.map(x => (x._1, x._2)) //(userID, (movieID, rating)) val userID_movieID_rating: RDD[(String, (String, String))] = Utils.ratingsRdd.map(x => (x._1, (x._2, x._3))) //(userID, (sex, (movieID, rating))) ---> (sex, movieID, rating) val movieID_rating: RDD[(String, String, String)] = userID_sex.join(userID_movieID_rating).map(x => (x._2._1, x._2._2._1, x._2._2._2)) //((sex, movieID), Iterable[(sex, movieID, rating)]) ---> (movieID, (sex, avg)) val movieID_sex_avg: RDD[(String, (String, Double))] = movieID_rating.groupBy(x => (x._1, x._2)).map(x => { var sum, avg = 0d val list: List[(String, String, String)] = x._2.toList if (list.size > 50) { list.map(x => ( sum += x._3.toInt )) avg = sum * 1.0 / list.size } (x._1._2, (x._1._1, avg)) }) //(movieID, movieName) val movieID_movieName: RDD[(String, String)] = Utils.movieRdd.map(x => (x._1, x._2)) //sex_movieID_avg与movie进行关联 (movieID, ((sex, avg), movieName)) ---> (sex, movieName, avg) val sex_movieName_avg: RDD[(String, String, Double)] = movieID_sex_avg.join(movieID_movieName) .map(x => (x._2._1._1, x._2._2, x._2._1._2)).sortBy(x => (x._1, x._3), false) sex_movieName_avg.take(10).foreach(println(_)) sex_movieName_avg.filter(_._1 == "F").take(10).foreach(println(_)) } }
第三问:
package movie_rating import org.apache.spark.rdd.RDD /** * Utils.usersRdd:对应字段中文解释:用户 id,性别,年龄,职业,邮政编码 * Utils.movieRdd:对应字段中文解释:电影 ID,电影名字,电影类型 * Utils.ratingsRdd:对应字段中文解释:用户 ID,电影 ID,评分,评分时间戳 */ object Demand03 { /** * 3、分别求男性,女性看过最多的 10 部电影(性别,电影名) */ def main(args: Array[String]): Unit = { //(userID, sex) val userID_sex: RDD[(String, String)] = Utils.usersRdd.map(x => (x._1, x._2)) //(userID, movieID) val userID_movieID: RDD[(String, String)] = Utils.ratingsRdd.map(x => (x._1, x._2)) //(movieID, name) val movieID_name: RDD[(String, String)] = Utils.movieRdd.map(x => (x._1, x._2)) //(userID, (sex, movieID)) ---> (movieID, sex) val movieID_sex: RDD[(String, String)] = userID_sex.join(userID_movieID).map(x => (x._2._2, x._2._1)) //关联movieID_sex和movieID_name (movieID, (sex, name)) ---> (movieID, sex, name) val movieID_sex_name: RDD[(String, String, String)] = movieID_sex.join(movieID_name) .map(x => (x._1, x._2._1, x._2._2)) //((sex, name), Iterable[(movieID, sex, name)]) ---> (sex, name, times) val sex_name_times: RDD[(String, String, Int)] = movieID_sex_name.groupBy(x => (x._2, x._3)).map(x => (x._1._1, x._1._2, x._2.toList.size)).sortBy(x => (x._1, x._3), false) //输出结果 sex_name_times.take(10).foreach(println(_)) sex_name_times.filter(_._1 == "F").take(10).foreach(println(_)) } }
第四问
package movie_rating import org.apache.spark.rdd.RDD /** * Utils.usersRdd:对应字段中文解释:用户 id,性别,年龄,职业,邮政编码 * Utils.movieRdd:对应字段中文解释:电影 ID,电影名字,电影类型 * Utils.ratingsRdd:对应字段中文解释:用户 ID,电影 ID,评分,评分时间戳 */ object Demand04 { /** * 4、年龄段在“18-24”的男人,最喜欢看 10 部电影(输出电影id和电影名字) */ def main(args: Array[String]): Unit = { // 年龄段在“18-24”的男人的userID (userID, (sex, age)) val userID_sex_age: RDD[(String, (String, Int))] = Utils.usersRdd.map(x => (x._1, (x._2, x._3.toInt))).filter(x =>{ x._2._2 >= 18 && x._2._2 <= 24 && x._2._1 == "M" } ) //(userID, (movieID, rating)) val userID_movieID_rating: RDD[(String, (String, Int))] = Utils.ratingsRdd.map(x => (x._1, (x._2, x._3.toInt))) //关联userID与userID_movieID_rating (userID, ((sex, age), (movieID, rating))) ---> (movieID, rating) // --->(movieID, Iterable(movieID, rating)) ---> (movieID, avg) val movieID_avg : RDD[(String, Double)] = userID_sex_age.join(userID_movieID_rating).map(x => (x._2._2._1, x._2._2._2)) .groupByKey().map(x => { var avg = 0d val len: Int = x._2.size if (len > 50){ avg = 1.0 * x._2.sum / len } (x._1, avg) }) //(movieID, name) val movieID_name: RDD[(String, String)] = Utils.movieRdd.map(x => (x._1, x._2)) //关联movieID_avg与movieID_name (movieID, (avg, name)) val name_avg: RDD[(String, Double)] = movieID_avg.join(movieID_name).map(x => (x._2._2, x._2._1)).sortBy(_._2, false) //输出结果 name_avg.take(10).foreach(println(_)) } }
第五问
package movie_rating import org.apache.spark.rdd.RDD /** * Utils.usersRdd:对应字段中文解释:用户 id,性别,年龄,职业,邮政编码 * Utils.movieRdd:对应字段中文解释:电影 ID,电影名字,电影类型 * Utils.ratingsRdd:对应字段中文解释:用户 ID,电影 ID,评分,评分时间戳 */ object Demand05 { /** * 5、求 movieid = 2116 这部电影各年龄段(因为年龄就只有 7 个,就按这个 7 个分就好了) * 的平均影评(年龄段,影评分) */ def main(args: Array[String]): Unit = { // 获得movieID = 2116 (userID, rating) val userID_rating: RDD[(String, Int)] = Utils.ratingsRdd.filter(_._2 == "2116").map(x => (x._1, x._3.toInt)) //(userID, age) val userID_age: RDD[(String, String)] = Utils.usersRdd.map(x => (x._1, x._3)) //关联userID_age和userID_rating (userID, (age, rating)) --->(age, rating) ---> (age, Iterable(rating)) val age_avg: RDD[(String, Double)] = userID_age.join(userID_rating).map(x => (x._2._1, x._2._2)).groupByKey() .map(x => (x._1, x._2.sum * 1.0 / x._2.size)) //输出结果 age_avg.sortByKey().foreach(println(_)) } }
第六问
package movie_rating import org.apache.spark.rdd.RDD /** * Utils.usersRdd:对应字段中文解释:用户 id,性别,年龄,职业,邮政编码 * Utils.movieRdd:对应字段中文解释:电影 ID,电影名字,电影类型 * Utils.ratingsRdd:对应字段中文解释:用户 ID,电影 ID,评分,评分时间戳 */ object Demand06 { /** * 6、求最喜欢看电影(影评次数最多)的那位女性评最高分的 10 部电影的平均影评分 * (观影者userID,电影名,影评分) */ def main(args: Array[String]): Unit = { //(userID, Iterable(userID, movieID, rating, time_stamp)) ---> (userID, times) val userID_times: RDD[(String, Int)] = Utils.ratingsRdd.groupBy(_._1).map(x => (x._1, x._2.size)) //(userID, (sex, times))找到最喜欢看电影(影评次数最多)的那位女性的userID val userID: String = Utils.usersRdd.map(x => (x._1, x._2)).join(userID_times).filter(_._2._1 == "F") .sortBy(_._2._2, false).map(_._1).first() //获得userID用户评分最高的10部电影的movieID val movieID: Array[(String, Int)] = Utils.ratingsRdd.filter(_._1 == userID).map(x => (x._2, x._3.toInt)) .sortBy(_._2, false).take(10) //获得该10部电影的平均影评分 val movieID_rating: RDD[(String, String)] = Utils.ratingsRdd.map(x => (x._2, x._3)) //关联movieID和movieID_rating (movieID, (rat1, rating)) ---> (movieID, Iterable(rating)) --> (movieID, avg) val movieID_avg = Utils.sc.makeRDD(movieID).join(movieID_rating).map(x => (x._1, x._2._2.toInt)) .groupByKey().map(x => { var avg = 0d if (x._2.size >= 50) { avg = x._2.sum * 1.0 / x._2.size } (x._1, avg) }) //(movieID, (name, avg)) ---> (UserID, name, avg) val userID_name_avg: RDD[(String, String, Double)] = Utils.movieRdd.map(x => (x._1, x._2)) .join(movieID_avg).map(x => (userID, x._2._1, x._2._2)).sortBy(_._3, false) userID_name_avg.foreach(println(_)) } }
第七问
package movie_rating import org.apache.spark.rdd.RDD /** * Utils.usersRdd:对应字段中文解释:用户 id,性别,年龄,职业,邮政编码 * Utils.movieRdd:对应字段中文解释:电影 ID,电影名字,电影类型 * Utils.ratingsRdd:对应字段中文解释:用户 ID,电影 ID,评分,评分时间戳 */ object Demand07 { /** * 7、求好片(评分>=4.0)最多的那个年份的最好看的 10 部电影(电影id, 电影名,平均评分) */ def main(args: Array[String]): Unit = { //1、找到所有的好片的movieID //(movieID, rating) ---> (movieID, Iterable(rating)) ---> (movieID, avg)(avg >= 4.0) val movieID_avg :RDD[(String, Double)]= Utils.ratingsRdd.map(x => (x._2, x._3.toInt)).groupByKey().map(x =>{ var avg = 0d if(x._2.size >= 50) avg = x._2.sum * 1.0 / x._2.size (x._1, avg) }).filter(_._2 >= 4.0) //(movieID, (name, year)) val movieID_name_year: RDD[(String, (String, String))] = Utils.movieRdd.map(x => (x._1, (x._2, x._2.substring(x._2.length - 5, x._2.length - 1)))) //2、找到好片最多的年代 //关联movieID_avg与movieID_name_year,(movieID, (avg, (name, year))) --> (year, Iterable(movieID)) val year_count: (String, Int) = movieID_avg.join(movieID_name_year).map(x => (x._2._2._2, x._1)) .groupByKey().map(x => (x._1, x._2.size)).sortBy(_._2, false).first() //3、找到该年最好看的10部电影 //(movieID, name) ---> (movieID, (name, avg)) ---> (movieID, name, avg) val movieID_name_avg = movieID_name_year.filter(_._2._2 == year_count._1).map( x => (x._1, x._2._1)) .join(movieID_avg).map(x => (x._1, x._2._1, x._2._2)).sortBy(_._3, false).take(10) //输出结果 movieID_name_avg.foreach(println(_)) } }
第八问
package movie_rating import org.apache.spark.rdd.RDD /** * Utils.usersRdd:对应字段中文解释:用户 id,性别,年龄,职业,邮政编码 * Utils.movieRdd:对应字段中文解释:电影 ID,电影名字,电影类型 * Utils.ratingsRdd:对应字段中文解释:用户 ID,电影 ID,评分,评分时间戳 */ object Demand08 { /** * 8、求 1997 年上映的电影中,评分最高的 10 部 Comedy 类电影(电影id,电影名字,类型,平均评分) */ def main(args: Array[String]): Unit = { //(movieID, (name, year, type)) val movieID_name_year_type: RDD[(String, (String, String, String))] = Utils.movieRdd .map(x => (x._1, (x._2, x._2.substring(x._2.length - 5, x._2.length - 1), x._3))) //找到所有1997年的comedy类型的电影 (movieID, (name, 1997, comedy)) val movieID_name_1997_comedy: RDD[(String, (String, String, String))] = movieID_name_year_type.filter(x => {x._2._2 == "1997" && x._2._3.toLowerCase.contains("comedy")} ) //(movieID, (rating, (name, 1997, comedy))) ---> (movieID, (name, comedy, rating)) val movieID_name_comedy_rating: RDD[(String, (String, String, String))] = Utils.ratingsRdd.map(x => (x._2, x._3)) .join(movieID_name_1997_comedy).map(x => (x._1, (x._2._2._1, x._2._2._3, x._2._1))) //(movieID, Iterable(rating)) ---> (movieID, avg) val movieID_avg: Array[(String, Double)] = movieID_name_comedy_rating.map(x => (x._1, x._2._3.toInt)) .groupByKey().map(x => { var avg = 0d if (x._2.size >= 50) avg = x._2.sum * 1.0 / x._2.size (x._1, avg) }).distinct().sortBy(_._2, false).take(10) //(movieID, (avg, (name, comedy, rating))) ---> (movieID, name, comedy, avg) val movieID_name_comedy_avg: RDD[(String, String, String, Double)] = Utils.sc.makeRDD(movieID_avg) .join(movieID_name_comedy_rating).map(x => (x._1, x._2._2._1, x._2._2._2, x._2._1)).distinct().sortBy(_._4, false) //输出结果 movieID_name_comedy_avg.foreach(println(_)) } }
第九问
package movie_rating import org.apache.spark.rdd.RDD /** * Utils.usersRdd:对应字段中文解释:用户 id,性别,年龄,职业,邮政编码 * Utils.movieRdd:对应字段中文解释:电影 ID,电影名字,电影类型 * Utils.ratingsRdd:对应字段中文解释:用户 ID,电影 ID,评分,评分时间戳 */ object Demand09 { /** * 9、该影评库中各种类型电影中评价最高的 5 部电影(类型,电影名,平均影评分) */ def main(args: Array[String]): Unit = { //获得所有电影的movieID,name,types (movieID, (name, types)) val movieID_name_types: RDD[(String, (String, String))] = Utils.movieRdd.map(x => (x._1, (x._2, x._3))) //获得所有的movieID,rating (movieID, rating) val movieID_rating: RDD[(String, String)] = Utils.ratingsRdd.map(x => (x._2, x._3)) //关联movieID_name_types与movieID_rating (movieID, ((name, types), rating)) ---> (types, name, rating) val types_name_rating: RDD[((String, String), Int)] = movieID_name_types.join(movieID_rating) .map(x => ((x._2._1._2, x._2._1._1), x._2._2.toInt)) //((types, name), Iterable(rating)) ---> (types, name, avg) val types_name_avg: RDD[(String, String, Double)] = types_name_rating.groupByKey().map(x => { var avg = 0d if (x._2.size >= 50) avg = x._2.sum * 1.0 / x._2.size (x._1._1, x._1._2, avg) }) //(types, name, avg) 划分types:将Action|Adventure|Comedy|Sci-Fi拆开 var tempArray: Array[(String, String, Double)] = Array(("", "", 0d)) types_name_avg.collect().foreach(x => { //Action|Adventure|Comedy|Sci-Fi ---> Arrays(Action, Adventure, Comedy, Sci-Fi) val types: Array[String] = x._1.split("\\|") //将所有的types_name_avg中的元素拆分后存于tempArray数组中 tempArray = types.map((_, x._2, x._3)).union(tempArray) }) //(type, name, avg) 包含所有类型电影的排序 val type_name_avg = Utils.sc.makeRDD(tempArray).filter(_._3 > 0).sortBy(x => (x._1, x._3), false) //(type, Iterable(type, name, avg)) 打印前五 type_name_avg.groupBy(_._1).sortByKey().foreach(x => { var count = 0 val list: List[(String, String, Double)] = x._2.toList while(count < list.size && count < 5){ println(list(count)) count += 1 } println() }) } }
第十问
package movie_rating import org.apache.spark.rdd.RDD /** * Utils.usersRdd:对应字段中文解释:用户 id,性别,年龄,职业,邮政编码 * Utils.movieRdd:对应字段中文解释:电影 ID,电影名字,电影类型 * Utils.ratingsRdd:对应字段中文解释:用户 ID,电影 ID,评分,评分时间戳 */ object Demand10 { /** * 10、各年评分最高的电影类型(年份,类型,影评分) */ def main(args: Array[String]): Unit = { //(movieID, year) val movieID_year: RDD[(String, String)] = Utils.movieRdd.map(x => (x._1, (x._2.substring(x._2.length - 5, x._2.length - 1)))) //(movieID, rating) ---> (movieID, Iterable(rating)) ---> (movieID, avg) val moviID_avg: RDD[(String, Double)] = Utils.ratingsRdd.map(x => (x._2, x._3.toDouble)).groupByKey() .map(x => (x._1, x._2.sum / x._2.size)) //关联movieID_year和moviID_avg (movieID, (year, avg)) ---> (year, (movieID, avg)) val year_mocvieID_avg: RDD[(String, (String, Double))] = movieID_year.join(moviID_avg) .distinct().map(x => (x._2._1, (x._1, x._2._2))) //(year, (movieID, avg)) ---> (year, Iterable((movieID, avg))) ---> (movieID, (year, topavg)) val year_movieID_topavg: RDD[(String, (String, Double))] = year_mocvieID_avg.groupByKey().map(x => { val list: List[(String, Double)] = x._2.toList.sortBy(-_._2) (list(0)._1, (x._1, list(0)._2)) }) //(movieID, (type, (year, topavg)) ---> (year, type, topavg) val year_type_topavg: RDD[(String, String, Double)] = Utils.movieRdd.map(x => (x._1, x._3)) .join(year_movieID_topavg).map(x => (x._2._2._1, x._2._1, x._2._2._2)).sortBy(_._1, false) //输出结果 year_type_topavg.foreach(println(_)) } }
标签:scala 获得 for list 分时 top apache rdd 打印
原文地址:https://www.cnblogs.com/wang-bing/p/9129483.html