R 手动将颜色添加到Shining/ggplot

我正在尝试创建一个闪亮的应用程序，用户可以在其中选择三列中的哪一列随着时间的推移进行绘制，包括三个候选列的百分比。到目前为止，实际的情节是完美的，但我想添加一些颜色，使Cand_1得到一条蓝线，Cand_2得到一条绿线，Cand_3得到一条红线。我尝试在变量名周围使用

Plot+scale\u color\u manuall=“c”（“Cand\u 1”=“蓝色”、“Cand\u 2”=“绿色”、“Cand\u 3”=“红色”）

加上和不加上“”，在

aes（）

中也使用

if

，以便：

Plot <- Plot + geom_line(aes(month, !! sym(input$cand)),  group = 1, if(input$cand == "Cand_1){
colour = "blue"}
if(input$cand == "Cand_2"){colour = "green"}
if(input$cand == "Cand_2"){colour = "red})

下面是一些示例数据：

Month   Cand_1  Cand_2  Cand_3
2019-02-01  60,7    90,1    86,2
2019-03-01  58,9    90,2    80,3
2019-04-01  47,3    88,3    84,6
2019-05-01  54,5    87,3    90
2019-06-01  50,6    86      89
2019-07-01  49,8    84,2    87,1

---

你不能这样分配颜色

Plot <- Plot + geom_line(aes(month, !! sym(input$cand)),  group = 1, if(input$cand == "Cand_1){
colour = "blue"}
if(input$cand == "Cand_2"){colour = "green"}
if(input$cand == "Cand_2"){colour = "red})

还有一些较短的方法：

color.list <- list(Cand_1 = "blue", Cand_2 = "green", Cand_3 = "red")

Plot <- Plot + geom_line(aes(month, !! sym(input$cand)), group = 1),
  colour = color.list[[input$cand]])

color.list
Plot <- Plot + geom_line(aes(month, !! sym(input$cand)),  group = 1, colour = <your decision here>)

Plot <- Plot + geom_line(aes(month, !! sym(input$cand)),  group = 1),
  colour = if(input$cand == "Cand_1") "blue" else 
if(input$cand == "Cand_2")"green" else
if(input$cand == "Cand_3") "red")

color.list <- list(Cand_1 = "blue", Cand_2 = "green", Cand_3 = "red")

Plot <- Plot + geom_line(aes(month, !! sym(input$cand)), group = 1),
  colour = color.list[[input$cand]])