1. 绘图函数(graphics 包)
- plot / hist / boxplot / points / lines / text / title / axis
- 调用函数会启用一个图形设备并在设备上绘图
· 基本绘图系统 + 屏幕设备
2. plot()
- plot(x, y, ...)
- 重要参数:xlab / ylab / lwd / lty / pch / col
- 查看其他参数:?par
· par() 用于设置全局参数(作用于R中所有plot绘图)
- bg / mar / las / mfrow / mfcol
· 这些参数可以在每次plot之前进行修改
3. 实践
hist(airquality$Wind, xlab="Wind")
# 直方图,风速值的频率
boxplot(airquality$Wind, xlab="Wind", ylab="Speed(mph)")
# 风速的箱图
boxplot(Wind~Month, airquality, xlab="Month", ylab="Speed(mph)")
# 按月份的风速箱图
plot(airquality$Wind, airquality$Temp)
# 风速和对应温度的散点图
with(airquality, plot(Wind, Temp, main="Wind and Temp in NYC"))
# with函数
title(main="Wind and Temp in NYC")
# 添加标题
with(airquality, plot(Wind, Temp, main="Wind and Temp in NYC", type="n"))
# 图的框架
with(subset(airquality, Month==9), points(Wind,Temp,col="red"))
# 9月红点
with(subset(airquality, Month==5), points(Wind,Temp,col="blue"))
# 5月蓝点
with(subset(airquality, Month %in%c(6,7,8)), points(Wind,Temp,col="black"))
# 其他月黑点
fit <- lm(Temp~Wind, airquality)
# lm函数:拟合线性模型
abline(fit, lwd=2)
# 添加直线,线宽为2
legend("topright", pch=1, col=c("red","blue","black"),legend=c("Sep","May","Other"))
# 添加图例说明
![](https://img.laitimes.com/img/_0nNw4CM6IyYiwiM6ICdiwiIn5GcuUDM4gTO5EzM30SNzMzMxADMwITMyIDM3EDMy0SM1cTOxATMvwlMwcTMwIzLcFTN3kTMwEzLcd2bsJ2Lc12bj5ycn9Gbi52YuUTMwIzcldWYtl2Lc9CX6MHc0RHaiojIsJye.png)
4. 全局参数
- 通过命令 ?par 查看帮助文档
par("bg")
par("col")
par("mar") # (bottom, left, top, right)
par("mfrow")
# 几行几列的图,按行排列
par("mfcol")
# 几行几列的图,按列排列
par(mfrow=c(1,2))
# 一行两列的图
hist(airquality$Temp)
hist(airquality$Wind)
par(mfrow=c(1,1))
# 一行一列的图
boxplot(airquality$Temp)
par(mfcol=c(2,1))
# 两行一列的图
hist(airquality$Temp)
hist(airquality$Wind)
转载于:https://www.cnblogs.com/wnzhong/p/6425147.html