Interacting with checkboxes in Rshiny for overlapping plots - r

Question

I am struggling trying to graph two overlaying plots and add checkboxes fro displaying them in my Rshiny app. I am using the following code:
library(shiny)
library(shinyjs)
mpgData <- mtcars
ui <- fluidPage(
# Application title
titlePanel("Test"),
# Sidebar with checkboxes to select plot
sidebarLayout(
sidebarPanel(
helpText("Select type of plot:"),
checkboxGroupInput("checkPlot",
label = ("Plots"),
choices=c("Baseline","Scenario A"),
selected = c("Baseline","Scenario A")
)
),
mainPanel(
textOutput("overview"),
plotOutput("plot")
)
)
)
server <- function(input, output, session) {
#get Check group input (type of plot)
checkedVal <- reactive({
as.vector(input$checkPlot)
})
#plot
output$plot <- renderPlot({
if(("Baseline" %in% checkedVal()) & ("Scenario A" %in% checkedVal()))
# first plot
plot(mpgData$mpg, mpgData$cyl, type='l',col="steelblue",ylim=range(c(mpgData$cyl,mpgData$disp)))
# second plot
par(new = TRUE)
plot(mpgData$mpg, mpgData$disp, type = "l",col="red", ylim=range(c(mpgData$cyl,mpgData$disp)), axes = FALSE, xlab = "", ylab = "")
if ("Baseline" %in% checkedVal())
plot(mpgData$mpg, mpgData$cyl, type='l',col = "steelblue")
if ("Scenario A" %in% checkedVal())
plot(mpgData$mpg, mpgData$disp, type='l',col = "red")
})
}
shinyApp(ui, server)
My checkboxes seem to be working out alright when I just want one graph to be displayed, however, there's definitely an issue when I want to display both on the same axes. Most examples I saw were a little too complex for me to understand and break down, so I tired to infer from previous R knowledge, but clearly I'm off.
any help is much appreciated !

Answer 1

If you were trying to add the baseline on the existing graph, you could use the lines function, as below. Although if for your particular data-set, the base line is really negligible compared to the original plot, you need to use a package other than 'base', like 'ggplot'.
library(shiny)
library(shinyjs)
mpgData <- mtcars
ui <- fluidPage(
# Application title
titlePanel("Test"),
# Sidebar with checkboxes to select plot
sidebarLayout(
sidebarPanel(
helpText("Select type of plot:"),
checkboxGroupInput("checkPlot",
label = ("Plots"),
choices=c("Baseline","Scenario A"),
selected = c("Baseline","Scenario A")
)
),
mainPanel(
textOutput("overview"),
plotOutput("plot")
)
)
)
server <- function(input, output, session) {
#get Check group input (type of plot)
checkedVal <- reactive({
as.vector(input$checkPlot)
})
#plot
# first plot
output$plot <- renderPlot({
if(("Baseline" %in% checkedVal()) & ("Scenario A" %in% checkedVal()))
{ plot(mpgData$mpg, mpgData$cyl, type='l',col="steelblue",ylim=range(c(mpgData$cyl,mpgData$disp)))
lines(mpgData$mpg, mpgData$disp, type = "l",col="red")
}
else if("Baseline" %in% checkedVal())
{
plot(mpgData$mpg, mpgData$cyl, type='l',col = "steelblue")
}
else if("Scenario A" %in% checkedVal())
{
plot(mpgData$mpg, mpgData$disp, type='l',col = "red")
}
})
}
shinyApp(ui, server)
Please let me know if this works for you.