箱線圖函數(shù)：boxplot(x, ...)

## S3 method for class 'formula'

boxplot(formula, data = NULL, ..., subset, na.action = NULL)

## Default S3 method:

boxplot(x, ..., range = 1.5, width = NULL, varwidth = FALSE,? ?? ???notch = FALSE, outline = TRUE, names, plot = TRUE,? ?? ???border = par("fg"), col = NULL, log = "",? ?? ???pars = list(boxwex = 0.8, staplewex = 0.5, outwex = 0.5),? ?? ???horizontal = FALSE, add = FALSE, at = NULL)

參數(shù)說明及示例解釋：1、formula:一個(gè)公式，形式為y~A（類別型變量A的每個(gè)值并列地生成數(shù)值型變量y的箱線圖）或y～A*B

par(mfrow=c(1,2))

boxplot(mpg~cyl,data = mtcars,main="car mileage data",xlab="number of cylinders", ylab="miles per gallon"）

boxplot(mpg~cyl*am,data = mtcars,main="car mileage data",xlab="number of cylinders")

2、varwidth:取值TRUE，繪制的箱線圖的寬度與其樣本大小的平方根成正比。

代碼及圖形：

par(mfrow=c(1,2))

boxplot(mpg~cyl,data = mtcars,main="car mileage data",xlab="number of cylinders",

? ?? ???ylab="miles per gallon")

boxplot(mpg~cyl,data = mtcars,varwidth=TRUE,

? ?? ???main="car mileage data",xlab="number of cylinders",ylab="miles per gallon")

3、width:繪制每個(gè)箱線圖的相對寬度，取值向量；

par(mfrow=c(1,2))

boxplot(mpg~cyl,data = mtcars,main="car mileage data",xlab="number of cylinders",

? ?? ???ylab="miles per gallon")

boxplot(mpg~cyl,data = mtcars,width=c(1,2,3),

? ?? ???main="car mileage data",xlab="number of cylinders",ylab="miles per gallon")

4、notch:取值true，可繪制含凹槽的箱線圖；

par(mfrow=c(1,2))

boxplot(mpg~cyl,data = mtcars,main="car mileage data",xlab="number of cylinders",

? ?? ???ylab="miles per gallon")

boxplot(mpg~cyl,data = mtcars,notch=TRUE,

? ?? ???main="car mileage data",xlab="number of cylinders",ylab="miles per gallon")

5、outline：默認(rèn)取值TRUE,繪制離群值。如取值FALSE，不繪制離群值；

par(mfrow=c(1,2))

boxplot(mpg~cyl,data = mtcars,notch=TRUE,

? ?? ???main="car mileage data",xlab="number of cylinders",ylab="miles per gallon")

boxplot(mpg~cyl,data = mtcars,notch=TRUE,outline=FALSE,

? ?? ???main="car mileage data",xlab="number of cylinders",ylab="miles per gallon")

6、names：每個(gè)箱線圖下的組標(biāo)簽；

par(mfrow=c(1,2))

boxplot(mpg~cyl,data = mtcars,

? ?? ???main="car mileage data",xlab="number of cylinders",ylab="miles per gallon")

boxplot(mpg~cyl,data = mtcars,names=c(1,2,3),

? ?? ???main="car mileage data",xlab="number of cylinders",ylab="miles per gallon")

7、boxwex:取值向量，控制箱線圖的寬度。par(mfrow=c(1,2))

boxplot(mpg~cyl,data = mtcars,

? ?? ???main="car mileage data",xlab="number of cylinders",ylab="miles per gallon")

boxplot(mpg~cyl,data = mtcars,boxwex=c(0.5,1,1.5),

? ?? ???main="car mileage data",xlab="number of cylinders",ylab="miles per gallon")

8、staplewex:最小值、最大值對應(yīng)的釘線寬度的調(diào)整，取值向量；

par(mfrow=c(1,2))

boxplot(mpg~cyl,data = mtcars,

? ?? ???main="car mileage data",xlab="number of cylinders",ylab="miles per gallon")

boxplot(mpg~cyl,data = mtcars,staplewex=c(0.5,1,1.5),

? ?? ???main="car mileage data",xlab="number of cylinders",ylab="miles per gallon")

9、outwex:取值向量。離群線寬度擴(kuò)展，擴(kuò)展比例與盒寬成正比。