R_assignment#ch14

1請設計程式，此程式會要求輸入姓名，然後回應”Welcome”和所輸入的姓名

ch14_1 <- function( )

{

    cat("Please enter your name, press /Enter/ to end")

    x1 <- scan(what = character())

    cat("Welcome~", x1)

}

2.重新輸入上一個程式，但將輸出轉至exer14_2.txt

ch14_2 <- function( )

{

    cat("Please enter your name, press /Enter/ to end")

    x1 <- scan(what = character())

    cat("Welcome~", x1, file = "~/exer14_2.txt")

}

3.使用Scan( )讀取txt之10筆資料，計算總合、平均、最大及最小值

ch14_3 <- function()
{
    x1 <- scan("C:/Users/veryv/OneDrive/桌面/Exercise.txt", sep = ",")
    cat("Sum=", sum(x1), "\n")
    cat("Mean=", mean(x1), "\n")
    cat("Max=", max(x1), "\n")
    cat("Min=", min(x1))
}

4.參考前例，將執行結果輸入exer14_3.txt

ch14_4 <- function()
{
    x1 <- scan("C:/Users/veryv/OneDrive/桌面/Exercise.txt", sep = ",")
    cat("Sum=", sum(x1),"\n","Mean=", mean(x1),"\n",
        "Max=", max(x1),"\n","Min=", min(x1),file = "~/exer14_3.txt")
}

5.讀取茶銷售量excel表並計算:各茶種年度總銷售量、各茶種年度總銷售額、各業務員年度總銷售額

ch14_5 <- function( )
{
    excel <- file.path("C:/Users/veryv/OneDrive/桌面/Test.csv")
    xCSV <- read.csv(excel, sep = ",")
    tea.info <- matrix(c(tapply(xCSV$Quantity, xCSV$Product, sum),
                         tapply(xCSV$Revenue, xCSV$Product, sum)),
                       nrow = 2, byrow = T)
    colnames(tea.info) <- c("BlackTea ", "Green Tea")
    rownames(tea.info) <- c("year_quant", "year_rev")
    Sales <- tapply(xCSV$Revenue, xCSV$Name, sum)
    answer <- list(TeaInfo = tea.info, RevBySales = Sales)
    print(answer)
}