参数说明:breaks:控制组的数量,可取值向量或数字;
代码及图形:
par(mfrow=c(1,2))
hist(mtcars$mpg,breaks=12)
hist(mtcars$mpg,breaks = c(8,14,20,26,32,38))
freq:逻辑值。默认TRUE,含义是根据频数绘制图形(即y轴为频数)。如取值FALSE,则表示根据概率密度(频数/样本量)绘制图形(y轴显示频率)
代码及图形:
par(mfrow=c(1,2))
hist(mtcars$mpg,breaks=12,freq = TRUE,main = "freq=true")
hist(mtcars$mpg,breaks = c(8,14,20,26,32,38),freq = FALSE,main = "freq=false")
probability:逻辑值。作用刚好与freq相反;
[size=13.333333015441895px]include.lowest:逻辑值,如取值true,等于breaks值的x将被纳入第一个图形中(如right=false则纳入后一个图形中)。当breaks为向量时会被忽略;
right:逻辑址,如取值true,分组是个左开右闭区间;
代码及图形:
par(mfrow=c(1,2))
hist(mtcars$mpg,breaks=10,freq = TRUE,right = FALSE)
hist(mtcars$mpg,breaks=10,freq = TRUE,right = TRUE)
其他参数用法与之前介绍的类似,在此不赘述。
补充:
1、rug函数(图形中添加轴须)
rug(x, ticksize = 0.03, side = 1, lwd = 0.5, col = par("fg"), quiet = getOption("warn") < 0, ...)参数说明:
x:数值型向量;
ticksize:绘制“rug”(须)的长度,默认是0.03.如取正值,轴下侧。取负值,在轴上方.
代码及图形对比解释:
par(mfrow=c(1,2))
hist(mtcars$mpg,breaks=10,freq = TRUE,right = FALSE)
rug(mtcars$mpg,ticksize = -0.03)
hist(mtcars$mpg,breaks=10,freq = TRUE,right = TRUE)
rug(jitter(mtcars$mpg))
side:轴须的绘制位置,取值1(默认),表示绘制在图形底部,取值3表示绘制在图形的顶部;
par(mfrow=c(1,2))
hist(mtcars$mpg,breaks=10,freq = TRUE,right = FALSE)
rug(mtcars$mpg,ticksize = -0.03,side = 1)
hist(mtcars$mpg,breaks=10,freq = TRUE,right = TRUE)
rug(jitter(mtcars$mpg),side = 3)
2、jitter(添加噪音值值数据中,即让原数据中相同的值添加一个小的随机值(±amount间的随机数),以避免重叠数据带来的影响)
函数:[size=13.333333015441895px]jitter(x, factor = 1, amount = NULL)
> jitter(mtcars$mpg,amount=0.01)
[1] 20.99450 20.99980 22.80086 21.39397 18.69349 18.09216 14.29322 24.39043
[9] 22.80962 19.19156 17.80318 16.40981 17.29272 15.20171 10.40764 10.39236
[17] 14.69092 32.39527 30.39363 33.90722 21.50977 15.49105 15.19958 13.30889
[25] 19.19576 27.29977 25.99279 30.39677 15.80832 19.69808 14.99176 21.40546
> mtcars$mpg
[1] 21.0 21.0 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 17.8 16.4 17.3 15.2 10.4
[16] 10.4 14.7 32.4 30.4 33.9 21.5 15.5 15.2 13.3 19.2 27.3 26.0 30.4 15.8 19.7
[31] 15.0 21.4