R Shiny Aesthetics 必须是长度为 1 或与数据 (8) 相同： y

Question

I am trying to plot multiple line charts in R Shiny and include checkboxes but I get an error message when I try to select more than one:

Error: Aesthetics must be either length 1 or the same as the data (8): y

I was able to plot them without error when using radio buttons, but checkboxes don't work. Here's my code:

library(readxl)
scores <- read.csv("newscores.csv")
weeks <- read.csv("weeks.csv")

library(ggplot2)

# ui.R
fluidPage(    
  # Give the page a title
  titlePanel("Fantasy Scores"),

  # Generate a row with a sidebar
  sidebarLayout(   
    # Define the sidebar with one input
    sidebarPanel(
      checkboxGroupInput("Team", label = h3("Select Team"), 
                         choices = c("Jeff","Jordan","Emmerts",
                                     "CJ","Jimmy","Phil",
                                     "Mat","Clegg","Rob","Shawn",
                                     "Seth","Truscott"))
    ),

    # Create a spot for the barplot
    mainPanel(
      plotOutput("phonePlot")  
    ) 
  )
)

# server.R
function(input, output) {

  # Fill in the spot we created for a plot
  output$phonePlot <- renderPlot({

    # Render a barplot
    ggplot(weeks, aes(x = Week, y = weeks[,input$Team])) + 
      geom_point() + geom_line()+ylim(59,160)+labs(title="Scores by Week",
                                                   x="Week",y="Points")+theme_minimal()
  })
}

And I pasted the dataset here (it's quite small) ( weeks.csv ):

structure(list(Week = c(1, 2, 3, 4, 5, 6, 7, 8), Jeff = c(150.4, 
91.5, 85.9, 122.9, 84.8, 116.6, 107.7, 101.3), Jordan = c(111, 
89.7, 127.6, 105.1, 115.1, 84, 108.9, 65.6), Emmerts = c(128.9, 
108.6, 92.7, 96.4, 78, 73.8, 131, 120.4), CJ = c(72.8, 104.1, 
84, 92.9, 62.8, 59.4, 82.2, 70.7), Jimmy = c(76.7, 68.4, 105.7, 
111.3, 97.3, 108.5, 102.6, 109.7), Phil = c(96.2, 83.9, 91.5, 
98.8, 81.7, 71.7, 78.3, 76.6), Mat = c(93.6, 106.2, 92.8, 87.5, 
131, 152.7, 142.6, 105.1), Clegg = c(117.9, 93.7, 98, 109.8, 
95.5, 104.2, 93.3, 103.1), Rob = c(80, 72.1, 74, 84.8, 111.7, 
105, 89.4, 77.6), Shawn = c(84.4, 116.6, 80.9, 106.1, 106.2, 
85.5, 88.4, 107.2), Seth = c(131.9, 98.6, 87.2, 111.7, 109, 125.7, 
96.3, 108.9), Truscott = c(100.5, 68.5, 88.8, 96.3, 91.5, 97.6, 
70.4, 111.3)), class = "data.frame", row.names = c("1", "2", 
"3", "4", "5", "6", "7", "8"))

Thanks for the help!

Answer 1

This is a solution:

library(reshape2)
library(dplyr)
library(ggplot2)

#input <- NULL
#input$Team <- c("Seth", "Truscott")

weeks_melt <- melt(weeks, "Week") 
p <- ggplot(weeks_melt, aes(x = Week, y = value, color = variable)) + geom_blank()

weeks_filtered <- week_melt %>% filter(variable %in% input$Team)
p + geom_line(data = weeks_filtered)

Note that we create a geom_blank() so ggplot creates the scales right away (so the colors are fixed even when you change what is selected), then we filter the data before adding the lines. If we don't fix the scales, all the colors and axis scales will vary each time you include or remove one of the factor levels, and this is not a good idea in most cases.

Shiny doesn't require you to build your plots in a single line, so you're free to filter your data before doing anything. Another point is that the first two non-commented lines could be outside your server function, to save a bit of time when transitioning between visualizations.