更改 ggplot2 中条形图和图例的默认颜色

Posted 2023-03-24

【中文标题】更改 ggplot2 中条形图和图例的默认颜色

【英文标题】：Change default color of bar plot and legend in ggplot2

【发布时间】：2021-09-17 01:54:07

【问题描述】：

这是动画 ggplot2 条形图的代码。我想将图例和条形图的默认颜色更改为凉爽的绿蓝色阴影。这里绘图和图例的默认颜色是蓝色。有人可以帮忙吗？

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)

【参考方案1】：

我建议看一下scale_fill_gradient()，在那里你可以设置颜色范围。在下面的示例中，我选择了从蓝色到红色的范围，因为我不确定您所说的“冷绿蓝色调”是什么意思。

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"
          )
        )