spark3.0教程：案例-统计各个性别人数、最高身高、最低身高（scala）-马育民老师

# 介绍

统计各个性别人数、最高身高、最低身高

# 数据格式

数据如下：

- 第一列：序号
- 第二列：性别
- 第三列：身高

```
1    F    170
2    M    178
3    M    174
4    F    165
```

# 生成数据

```
package top.malaoshi.sex

import org.apache.spark.SparkContext
import org.apache.spark.SparkConf

import scala.util.Random

object GeneratePeopleInfoHDFS {
  /**
   * 随机生成性别
   * @return
   */
  def getRandomGender(): String = {
    val rand = new Random()
    val randNum = rand.nextInt(2) + 1
    if (randNum % 2 == 0) {
      "M"
    } else {
      "F"
    }
  }

def main(args: Array[String]) {
    //这里注意端口和路径,要和配置里面的端口路径一样
//    val outputFile = "hdfs://hadoop1:8020/data/peopleinfo.txt"
    val path = "data/person_height"
    val conf = new SparkConf().setAppName("GeneratePersonHeightHDFS").setMaster("local[2]")
    val sc = new SparkContext(conf)
    val rand = new Random()
    val array = new Array[String](1000)

for (i <- 1 to 1000) {
      // 随机生成身高，单位厘米
      var height = rand.nextInt(190)
      if (height < 50) {
        height = height + 50
      }
      // 随机生成性别
      var gender = getRandomGender()
      // 如果男生身高低于100，增加100
      if (height < 100 && gender == "M") {
        height = height + 100
      }
      // 如果女生身高低于100，增加50
      if (height < 100 && gender == "F") {
        height = height + 50
      }
      // 将数据放入数组中
      array(i - 1) = i + " " + gender + " " + height
    }

val rdd = sc.parallelize(array)
    rdd.foreach(println)
    rdd.saveAsTextFile(path)
  }
}
```

# 统计身高

```
package top.malaoshi.sex

import org.apache.spark.SparkConf
import org.apache.spark.SparkContext
object CountPeopleInfo{
  def main(args:Array[String]){
    if (args.length<1){
      println("Usage: input file path")
      System.exit(1)
    }
    val conf = new SparkConf().setAppName("CountPeopleInfo").setMaster("local")
    val sc = new SparkContext(conf)
    val lines = sc.textFile(args(0),3)
    val maleInfo = lines
      .filter(line=>line.contains("M"))
      .map(line=>line.split(" "))
      .map(t=>(t(1)+" "+t(2)))
    val femaleInfo = lines
      .filter(line=>line.contains("F"))
      .map(line=>line.split(" "))
      .map(t=>(t(1)+" "+ t(2)))
    val maleHeightInfo = maleInfo
      .map(t=>t.split(" ")(1).toInt)
    val femaleHeightInfo = femaleInfo
      .map(t=>t.split(" ")(1).toInt)
    val lowestMale = maleHeightInfo
      .sortBy(x=>x,true)
      .first()
    val lowestFemale = femaleHeightInfo
      .sortBy(p=>p,true)
      .first()
    val highestMale = maleHeightInfo
      .sortBy(p=>p,false)
      .first()
    val highestFemale = femaleHeightInfo
      .sortBy(p=>p,false)
      .first()

println("Number of Male:"+ maleInfo.count())
    println("Number of Female:"+femaleInfo.count())
    println("Lowest Male:"+lowestMale)
    println("Lowest Female:"+lowestFemale)
    println("HighestMale:"+highestMale)
    println("HighestFemale:"+highestFemale)
  }
}
```

### 运行

按照下图操作：

[![](https://www.malaoshi.top/upload/0/0/1GW2Q0qFTMCO.png)](https://www.malaoshi.top/upload/0/0/1GW2Q0qFTMCO.png)

指定参数，如下图：

[![](https://www.malaoshi.top/upload/0/0/1GW2Q0qc8YSR.png)](https://www.malaoshi.top/upload/0/0/1GW2Q0qc8YSR.png)

### 执行结果

```
Number of Male:494
Number of Female:506
Lowest Male:100
Lowest Female:100
HighestMale:199
HighestFemale:188
```

原文出处：http://www.malaoshi.top/show_1GW2Q1cClJWw.html