A_c(3,4,4,3,2,3,1,3,5,2)
 A_scan()
 3
 4
 6
 7


 A[4]
 
 A_c(A,3,6,7)
 A

 A_c(rep(1,10))
 A

 A_c(rep(c(1,2),10))
 A

 A_c(rep(c(15,25,35,45),c(3,8,10,5)))
 A

 length(A)

 mean(A)

 sum(A)

 mean

 var(A)

 A-mean(A)
 
 (A-mean(A))^2
 sum((A-mean(A))^2)
 sum((A-mean(A))^2)/(length(A)-1)

 summary(A)
 SumA_summary(A)
 SumA[3]
 SumA[1]+SumA[6]

 hist(A)

 br_c(10,20,30,40,50)
 hist(A,breaks=br)
 plot(A)

 t.test(A,mu=30)
 t.test(A,mu=30,conf.level=0.90)
 t.test(A,mu=30,alternative="greater")
 t.test(A,mu=30,alternative="less")

 t.test(A,mu=28,alternative="greater")
 t.test(A,mu=28,alternative="less")
 
 B_c(5,5,6,7,4,4,3,5,6,5)
 summary(B)

 var(B)

 var(A)
 mean(A)

 var.test(A,B)
 B_B+26
 B

 mean(B)
 var(B)

 t.test(A,B,var.equal=F)

 set.seed(100)
 C_rnorm(100)
 C
 hist(C)

 C_rnorm(100)
 hist(C)
 t.test(C)

 cdf.compare(C)
 sort(C)
 ks.gof(C)