主要内容：
plot函数
1.数据——mtcars(R 内置数据集）
mtcars
结果：
> mtcars
mpg cyl disp hp drat wt qsec vs am gear carb
Mazda RX4 21.0 6 160.0 110 3.90 2.620 16.46 0 1 4 4
Mazda RX4 Wag 21.0 6 160.0 110 3.90 2.875 17.02 0 1 4 4
Datsun 710 22.8 4 108.0 93 3.85 2.320 18.61 1 1 4 1
Hornet 4 Drive 21.4 6 258.0 110 3.08 3.215 19.44 1 0 3 1
Hornet Sportabout 18.7 8 360.0 175 3.15 3.440 17.02 0 0 3 2
Valiant 18.1 6 225.0 105 2.76 3.460 20.22 1 0 3 1
Duster 360 14.3 8 360.0 245 3.21 3.570 15.84 0 0 3 4
Merc 240D 24.4 4 146.7 62 3.69 3.190 20.00 1 0 4 2
Merc 230 22.8 4 140.8 95 3.92 3.150 22.90 1 0 4 2
Merc 280 19.2 6 167.6 123 3.92 3.440 18.30 1 0 4 4
Merc 280C 17.8 6 167.6 123 3.92 3.440 18.90 1 0 4 4
Merc 450SE 16.4 8 275.8 180 3.07 4.070 17.40 0 0 3 3
Merc 450SL 17.3 8 275.8 180 3.07 3.730 17.60 0 0 3 3
Merc 450SLC 15.2 8 275.8 180 3.07 3.780 18.00 0 0 3 3
Cadillac Fleetwood 10.4 8 472.0 205 2.93 5.250 17.98 0 0 3 4
Lincoln Continental 10.4 8 460.0 215 3.00 5.424 17.82 0 0 3 4
Chrysler Imperial 14.7 8 440.0 230 3.23 5.345 17.42 0 0 3 4
Fiat 128 32.4 4 78.7 66 4.08 2.200 19.47 1 1 4 1
Honda Civic 30.4 4 75.7 52 4.93 1.615 18.52 1 1 4 2
Toyota Corolla 33.9 4 71.1 65 4.22 1.835 19.90 1 1 4 1
Toyota Corona 21.5 4 120.1 97 3.70 2.465 20.01 1 0 3 1
Dodge Challenger 15.5 8 318.0 150 2.76 3.520 16.87 0 0 3 2
AMC Javelin 15.2 8 304.0 150 3.15 3.435 17.30 0 0 3 2
Camaro Z28 13.3 8 350.0 245 3.73 3.840 15.41 0 0 3 4
Pontiac Firebird 19.2 8 400.0 175 3.08 3.845 17.05 0 0 3 2
Fiat X1-9 27.3 4 79.0 66 4.08 1.935 18.90 1 1 4 1
Porsche 914-2 26.0 4 120.3 91 4.43 2.140 16.70 0 1 5 2
Lotus Europa 30.4 4 95.1 113 3.77 1.513 16.90 1 1 5 2
Ford Pantera L 15.8 8 351.0 264 4.22 3.170 14.50 0 1 5 4
Ferrari Dino 19.7 6 145.0 175 3.62 2.770 15.50 0 1 5 6
Maserati Bora 15.0 8 301.0 335 3.54 3.570 14.60 0 1 5 8
Volvo 142E 21.4 4 121.0 109 4.11 2.780 18.60 1 1 4 2
2.plot
plot(mtcars$disp,mtcars$wt)
plot(mtcars$disp,mtcars$wt,pch = 16)
2.1 点图参数：
1）pch : 点的形状
2）cex : 点的缩放比例
cex = 1.5 #默认值的1.5倍大
3）col : 颜色
2.2 线图参数
4）type ：类型
type = "l" #线 type = "p" #点 type = "b" #点线
5）lty : 线条的类型
plot(mtcars$disp,mtcars$wt,type = "l",col = "blue",lty = 2) #lty = 2代表虚线
6）lwd : 线的粗细，默认为1
plot(mtcars$disp,mtcars$wt,type = "l",col = "blue",lty = 2,lwd = 2)
7）main : 添加标题
plot(mtcars$disp,mtcars$wt,type = "l",col = "blue",lty = 2,lwd = 2,
main = "disp vs mt")
8）sub : 副标题
plot(mtcars$disp,mtcars$wt,type = "l",col = "blue",lty = 2,lwd = 2,
main = "disp vs mt",sub = "a tu3")
9）xlab, ylab 坐标轴标签
plot(mtcars$disp,mtcars$wt,type = "l",col = "blue",lty = 2,lwd = 2,
main = "disp vs mt",sub = "a tu3", xlab = "disp", ylab = "wt")
10）xlim, ylim : 指定坐标轴范围
plot(mtcars$disp,mtcars$wt,type = "l",col = "blue",lty = 2,lwd = 2,
main = "disp vs mt",sub = "a tu3", xlab = "disp", ylab = "wt",
xlim = c(100,400),ylim = c(2,5))
11) abline : 添加辅助线（直线or 斜线）
#添加辅助线 abline(h=c(3,4), v=c(150,400)) #h:横线，v:竖线
plot(mtcars$disp,mtcars$wt,type = "l",col = "blue",lty = 2,lwd = 2,
main = "disp vs mt",sub = "a tu3", xlab = "disp", ylab = "wt",
xlim = c(100,400),ylim = c(2,5))
#添加辅助线
abline(h=c(3,4), v=c(150,400), col = "red", lty = 3, lwd=1.5) #h:横线，v:竖线
mtcars <- mtcars[order(mtcars$disp),]
plot(mtcars$disp,mtcars$wt,type = "l",col = "blue",lty = 2,lwd = 2,
main = "disp vs mt",sub = "a tu3", xlab = "disp", ylab = "wt",
xlim = c(100,400),ylim = c(2,5))
#添加回归线，用lm() 函数，先y值，再x值，中间用“~”链接。
abline(lm(mtcars$wt~mtcars$disp))
?mtcars
#提取子集
#提取vs列值等于0的所有数据
m0 <- subset(mtcars,vs==0)
#提取vs列值等于1的所有数据
m1 <- subset(mtcars,vs==1)
#画出vs列值等于0和1的mt列和disp列的关系图
plot(m0$disp,m0$wt,pch=16,col="blue",
xlim = range(mtcars$disp), ylim = range(mtcars$wt))
#不能再用plot(m1$disp,m1$wt,pch=17,col="green"),会覆盖上面的，用points()
points(m1$disp,m1$wt,pch=17,col="green")
12）legend ： 添加图例
#添加图例
legend("bottomright", title = "class of vs",
legend = c("V-shaped","straight"),
col = c("blue", "green"),
pch = c(16,17)) #点的类型
13）par() #全局修改图的参数
标签：disp,No.12,01,plot,mtcars,wt,可视化,type,col From： https://www.cnblogs.com/bltstop/p/18686484