spark学习02天-scala读取文件，词频统计

Posted 2021-12-30 students

1.在本地安装jdk环境和scala环境

 

2.读取本地文件：

 

scala> import scala.io.Source
import scala.io.Source

scala> val lines=Source.fromFile("F:/ziyuan_badou/file.txt").getLines().toList

lines: List[String] = List("With the development of civilization, it is the chil
dren‘s duty to study in school since they were small. As the young kids, it is t
heir nature to hang out for fun. ", "", "While for them, most of the time have b
een limited in the class. So they feel frustrated and don‘t have much passion to
 study. It is of great importance to develop ", "", "interest. The first thing i
s to broaden vision. The students can read travel books or watch tourist show, f
or anyone who cannot resist the charm of beautiful scenery ", "", and delicious
food. The second thing is taking the right attitude to exams. Never giving too m
uch pressure on getting high marks. The only thing we should do is to enjoy gain
ing knowledge.)

3.词频topN计算

scala> lines.map(x=>x.split(" ")).flatten.map(x=>(x,1)).groupBy(x=>x._1).map(x=>
(x._1,x._2.map(x=>x._2).sum)).toList.sortBy(x=>x._2).reverse
res0: List[(String, Int)] = List((the,7), (to,7), (is,6), (of,4), (The,4), (thin
g,3), (for,3), ("",3), (and,2), (much,2), (they,2), (it,2), (have,2), (in,2), (o
nly,1), (right,1), (show,,1), (exams.,1), (high,1), (since,1), (study,1), (study
.,1), (great,1), (we,1), (interest.,1), (develop,1), (As,1), (passion,1), (were,
1), (time,1), (them,,1), (children‘s,1), (development,1), (knowledge.,1), (It,1)
, (anyone,1), (Never,1), (nature,1), (enjoy,1), (first,1), (taking,1), (frustrat
ed,1), (books,1), (delicious,1), (So,1), (their,1), (resist,1), (should,1), (sma
ll.,1), (gaining,1), (While,1), (who,1), (on,1), (can,1), (been,1), (second,1),
(travel,1), (most,1), (scenery,1), (getting,1), (attitude,1), (cannot,1), (civil
ization,,1), (broaden,1), (out,1), (food.,1), (don‘t,1), (importance,1), (kid...