18

我的情节中有这五 (5) 个 geom_vline()，我希望它们具有不同的颜色。有没有办法做到这一点？

这是我的代码，

library(ggplot2)

x <- seq(-7, 8, length = 90)
tvalues <- dt(x,15)

qplot(x, tvalues) + geom_polygon(fill = "purple", colour = "purple", alpha = 0.5) + 
  geom_point(fill = "purple", colour = "purple", alpha = 0.2, pch = 21) +
  geom_vline(xintercept = c(a <- c(-2.27685371,  0.01661155,  
  0.33598194,  1.92426022), mean(a)), linetype = "dashed", colour = "red") + theme_bw() + xlab(bquote(bold('Average Tensile Strength (lb/in'^'2'*')'))) +
  ylab(expression(bold(P(x)))) +
  opts(title = expression(bold("Student t Distribution")), plot.title = theme_text(size = 20, colour = "darkblue"),
       panel.border = theme_rect(size = 2, colour = "red"))

这是输出，

在此处输入图像描述

注意图中的五条垂直线，我希望每条线都有不同的颜色，

我试过这个

library(colorRamps)
geom_vline(xintercept = c(a <- c(-2.27685371,  0.01661155,  
   0.33598194,  1.92426022), mean(a)), linetype = "dashed", colour = matlab.like(5))

但没用，再试一次

geom_vline(xintercept = c(a <- c(-2.27685371,  0.01661155,  
   0.33598194,  1.92426022), mean(a)), linetype = "dashed", colour = c("red","blue","green","yellow","orange"))

仍然不成功。

提前致谢！

4

2 回答 2

34

因此，您有点错过了ggplot2背后的基本思想，即您始终将所有数据放入一个data.frame映射中，并且映射的每个美学都对应于数据框中的一个变量。

你可以得到 5 条垂直线，每条线都有不同的颜色，有 5 次单独的调用，geom_vline但这错过了整个包的要点。相反，您创建一个数据框：

a <- c(-2.27685371,0.01661155,0.33598194,1.92426022)
vlines <- data.frame(xint = c(a,mean(a)),grp = letters[1:5])

我已经明确创建了一个分组变量grp来映射到colour. 然后我们添加图层并将美学映射到这些变量，使用aes：

qplot(x, tvalues) + 
  geom_polygon(fill = "purple", colour = "purple", alpha = 0.5) + 
  geom_point(fill = "purple", colour = "purple", alpha = 0.2, pch = 21) +
  geom_vline(data = vlines,aes(xintercept = xint,colour = grp), linetype = "dashed") + 
  theme_bw() + 
  xlab(bquote(bold('Average Tensile Strength (lb/in'^'2'*')'))) +
  ylab(expression(bold(P(x)))) +
  opts(title = expression(bold("Student t Distribution")), 
       plot.title = theme_text(size = 20, colour = "darkblue"),
       panel.border = theme_rect(size = 2, colour = "red"))

（颜色很难区分，因为它们是虚线，其中两个几乎在彼此之上。）

如果您从向过渡并开始将数据放入数据框而不是向量中，您将从ggplot2中获得更多收益。qplotggplot()

于 2012-06-19T14:09:19.317 回答
9

如果您只想放置一条线，添加以下内容将在红色和虚线geom处添加一条垂直线。x=1

+ geom_vline(aes(xintercept=1), colour="#BB0000", linetype="dashed")
于 2017-04-18T16:32:37.273 回答