合肥工业大学2022上半年R语言选修课作业，供参考
setwd("D:/")
A1 <- read.table("Scores.csv",sep=",",header=TRUE,encoding = 'UTF-8')#读取文件
dim(A1)
A1<-A1[,-4]
#1)
#使用dplyr包，剔除有缺失值的行
#na.omit(A1)也行
A1<-dplyr::filter(A1, !is.na(期末成绩))
A1
#2)
a<-(which(A1[,2]=="女"))
b<-(which(A1[,3]<20))
c=intersect(a,b)
Y<-A1[c,]
Y<-Y[,-2]
Y
#3)
d<-(which(A1[,4]>90))
g=intersect(d,c)
A1[g,1]
length(g)
#4)
A2 <- read.table("Scores.csv",sep=",",header=TRUE,encoding = 'UTF-8')
A2 <- A2[,-2]
A2 <- A2[,-4]
A2 <- A2[,-2]
#由于6)有排序要求，应在此处剔除有缺失值的行
A2<-dplyr::filter(A2, !is.na(期中成绩))
A2
#5)
A3<-merge(A1,A2,by="姓名")
A3
#6)
#A3[order(A3$"期末考试",-A3$"期中考试"),]
A3 = A3[order(-A3[,4],A3[,5]),]
运行截图涉及个人信息不发了
fun<-function(x,y){
i<-intersect(x,y) #交集
cat("交集为",i,sep = " ")
u<-union(x,y) #并集
cat("并集为",u,sep = " ")
}
v1=c(1,2,3,4,5,6)
v2=c(2,3,5,4,8,9,7)
v1
v2
fun(v1,v2)
运行截图：
