r-更改ggplot2中条形图和图例的默认颜色

Question

这是ggplot2条形图动画的代码。我想将图例和条形图的默认颜色更改为冷绿色-蓝色阴影。此处绘图和图例的默认颜色为蓝色。有人能帮忙吗

library(ggplot2)
library(shiny)
library(gganimate)
library(gifski)

undergradDATA <- read.csv(file="1-10 Undergraduates.csv", head=TRUE, sep=",")
ui <- fluidPage(
mainPanel(imageOutput("plot"))
)
server <- function(input, output) {
output$plot <- renderImage(
{
undergrad_plot <- ggplot(data = undergradDATA, aes(x = HEI, y = Undergrad, fill = Undergrad)) +

geom_col(colour = "white")
undergrad_plot + ggtitle("Ranking of Top 10 Pakistani HEI's w.r.t Undergraduates") +
theme(
plot.title = element_text(
hjust = 0.5,
colour = "darkolivegreen",
size = 17,
family = "mono"
)
)



anim <- undergrad_plot +
transition_states(Undergrad, wrap = FALSE) +
shadow_mark() +
enter_grow() +
enter_fade()

animate(anim, height = 500, width =600, fps = 5)


anim_save("underGradplot.gif") # New

# Return a list containing the filename
list(src = "underGradplot.gif", contentType = "image/gif")
},
deleteFile = TRUE
)
}
shinyApp(ui, server)

Answer 1

我建议看一下scale_fill_gradient()，在那里可以设置颜色范围。在下面的例子中，我选择了从蓝色到红色的范围，因为我不确定你说的"红色"是什么意思；冷绿色-蓝色阴影"；。

undergrad_plot <- ggplot(data = undergradDATA, aes(x = HEI, y = Undergrad, fill = Undergrad)) +
geom_col() + 
ggtitle("Ranking of Top 10 Pakistani HEI's w.r.t Undergraduates") +
scale_fill_gradient(low="blue", high="red") +
theme(
plot.title = element_text(
hjust = 0.5,
colour = "darkolivegreen",
size = 17,
family = "mono"
)
)