如何在geom_image()中使用多种颜色

Question

我很难弄清楚如何用ggimage高亮显示多种颜色。

很清楚如何将不同的图像设置为单个颜色(从小编)：

library("ggplot2")
library("ggimage")

set.seed(2017-02-21)
d <- data.frame(x = rnorm(10),
                y = rnorm(10),
                z = sample(c("A","B","C","A","B","C","A","B","C","A")),
                image = sample(c("https://www.r-project.org/logo/Rlogo.png",
                                 "https://jeroenooms.github.io/images/frink.png"),
                               size=10, replace = TRUE)
                )

ggplot(d, aes(x, y)) + geom_image(aes(image=image), color="firebrick")

我在示例中引入了另一列z，因为我正在使用的dataset有一个变量，我希望对其应用color美学。

我尝试了如何在ggplot() (和/或geom_point())调用中设置它，但没有得到我想要的输出：

ggplot(d, aes(x, y)) + geom_image(aes(image=image), color=d$z) 

Error in col2rgb(color) : invalid color name 'test'

它不接受多种颜色？

ggplot(d, aes(x, y)) + geom_image(aes(image=image), color = c("blue","red","green"))

我还尝试用RColorBrewer指定三种颜色

library(RColorBrewer)

my_color <- brewer.pal(3, "Set1")
ggplot(d, aes(x, y)) + geom_image(aes(image=image), color = my_color)

我非常感谢你帮我解决这个问题。

Answer 1

    set.seed(2017-02-21)
    d <- data.frame(x = rnorm(10),
                y = rnorm(10),
                z = sample(c("A","B","C","A","B","C","A","B","C","A")),
                image = sample(c("https://www.r-project.org/logo/Rlogo.png",
                                 "https://jeroenooms.github.io/images/frink.png"),
                               size=10, replace = TRUE)
)
    ggplot(d, aes(x, y,group=z)) + geom_image(aes(image=image,color=factor(z)))