Question

我很难设置图例并在重叠的直方图中更改颜色。出于某种原因，当我尝试更改颜色时，图例不再自定义。这是没有任何颜色规格的代码，你能帮帮我吗？

   # o - o - o  Preparing data o - o - o - o - o - o - o - o - o
   iris$Petal.Length.binary <- NA
   iris$Petal.Length.binary[iris$Petal.Length < 4.5] <- "low length"
   iris$Petal.Length.binary[iris$Petal.Length >= 4.5] <- "high length"
   iris$Petal.Length.binary <- factor(iris$Petal.Length.binary, levels=c("low length", "high length"))

   # o - o - o    Density plot   o - o - o - o - o - o - o - o - o
   Density <- ggplot(iris, aes(Sepal.Length, fill = Petal.Length.binary)) 
   Density2 <- 
(Density + 
 #_____________Change colour density___________ 
        geom_density(alpha = 0.3) + 
 #_____________Position the legend in bottom left___________
 theme(legend.justification=c(0,1), legend.position=c(0,1))  +
 #_____________Customising title___________ http://www.cookbook-r.com/Graphs/Titles_(ggplot2)/
 ggtitle('Title : Example Plot') +
 theme(plot.title = element_text(lineheight=0.9, face="bold")) +
 #_____________Labels___________
 labs(x='Sepal Length', y='Probability Density') +
 #_____________Customising legend___________
 scale_fill_discrete(name = "An irrelevant \nlegend title",
                     breaks=c("low length", "high length"),
                     labels=c("Low \nlength", "High \nlength")) +
 #_____________Increase spacing in legend categories___________     
 theme(legend.key.height=unit(1.5,"line")) +
 theme(legend.key.width=unit(1.2,"line")) ) 
 Density2

当我添加它时，有问题的一行会删除图例中的所有格式： scale_fill_manual（values = c（＆＃34;＃0000FF＆＃34;，＆＃34;＃FF0000＆＃34;））

最后一个问题，我喜欢图形，但是，ggplot2的默认颜色应该颠倒（浅蓝色，粉红色第二），有没有办法做到这一点？我无法在互联网上的任何地方找到默认颜色的十六进制代码。

基于Henrik的回复的正确代码

# o - o - o    Density plot   o - o - o - o - o - o - o - o - o
Density <- ggplot(iris, aes(Sepal.Length, fill = Petal.Length.binary)) 
Density2 <- 
   (Density + 
 #_____________Change colour density___________ 
 geom_density(alpha = 0.3) + 
 #_____________Position the legend in bottom left___________
 theme(legend.justification=c(0,1), legend.position=c(0,1))  +
 #_____________Customising title___________ http://www.cookbook-r.com/Graphs/Titles_(ggplot2)/
 ggtitle('Title : Example Plot') +
 theme(plot.title = element_text(lineheight=0.9, face="bold")) +
 #_____________Labels___________
 labs(x='Sepal Length', y='Probability Density') +
 scale_fill_manual(values=c("#0000FF", "#FF0000"),
                   name = "An irrelevant \nlegend title",
                   breaks=c("low length", "high length"),
                   labels=c("Low \nlength", "High \nlength")) +
 #_____________Increase spacing in legend categories___________     
 theme(legend.key.height=unit(1.5,"line")) +
 theme(legend.key.width=unit(1.2,"line")) ) 
 Density2

这是如何在第一张图中访问ggplot使用的2种颜色：

gg_color_hue <- function(n) {
  hues = seq(15, 375, length=n+1)
  hcl(h=hues, l=65, c=100)[1:n]
}

n = 2
cols = gg_color_hue(2)
str(cols) # the hex numbers :-)

在ggplot2重叠密度图中自定义图例和颜色

0 个答案: