ggplot帮助：为什么我的密度叠加层没有出现？

Posted 2021-04-23

我正在使用以下代码来使用最小值，均值和最大值创建概率分布函数：

a <- ggplot(Break_Even, aes(x =((rpert(4000, min=9677, mode=12776, max=16247, shape=4))))) 

a + geom_histogram(binwidth=200, color="black", fill="cadetblue") +
    geom_vline(aes(xintercept=mean(((rpert(4000, min=9677, mode=12776, max=16427, shape=4))))), color="coral", linetype="dashed", size=1) +
    geom_density() + 
    labs(y= "Frequency", x = "Break Even Quantity", title = "Break Even Probability Frequency Distribution") 

为什么我的密度叠加层不显示？

答案

如果不是常用软件包提供的功能，请提供信息。在这种情况下，我猜测rpert来自mc2d。您没有提供数据框Break_Even，但我可以看到它根本没有使用，但是一次创建并在一个数据上完成所有绘制就更有意义了。

library(mc2d)
library(ggplot2)

Break_Even = data.frame(x =rpert(4000, min=9677, mode=12776, max=16247,shape=4))

ggplot(Break_Even, aes(x=x)) +
geom_histogram(aes(y=..density..),binwidth=200, color="black", fill="cadetblue") +
geom_vline(aes(xintercept=mean(x)), color="coral", linetype="dashed", size=1) +
geom_density() + 
labs(y= "Frequency", x = "Break Even Quantity", title = "Break Even Probability Frequency Distribution")

如果要计算y轴的位置，请遵循here中的解决方案：

ggplot(Break_Even, aes(x=x)) +
geom_histogram(binwidth=200,color="black", fill="cadetblue") +
geom_vline(aes(xintercept=mean(x)), color="coral", linetype="dashed", size=1) +
geom_density(aes(y = ..density..*(nrow(Break_Even)*200))) + 
labs(y= "Frequency", x = "Break Even Quantity", title = "Break Even Probability Frequency Distribution")