Adding multiple reactive geom_lines to Shiny figure - r

Question

I'd like to include the reactive outputs of two data sets as different geom_lines in the same ggplotly figure. The code runs as expected when only one reactive data.frame is included as a geom_line. Why not two?
ui <- fluidPage(
sidebarLayout(
selectInput("Var1",
label = "Variable", #DATA CHOICE 1
selected = 10,
choices = c(10:100)),
selectInput("Var1",
label = "Variable2", #DATA CHOICE 2
selected = 10,
choices = c(10:100))
# Show a plot of the generated distribution
),
mainPanel(
plotlyOutput('plot') #Draw figure
)
)
server <- function(input, output) {
out <- reactive({
data.frame(x = rnorm(input$Var1), #Build data set 1
y = 1:input$Var1)
})
out2 <- reactive({
data.frame(x = rnorm(input$Var2), #Build data set 2
y = 1:input$Var2)
})
output$plot <- renderPlotly({
p <- ggplot() +
geom_line(data = out(), aes(x = x, y = y)) #Add both data sets in one ggplot
geom_line(data = out2(), aes(x = x, y = y), color = "red")
ggplotly(p)
})
}
# Run the application
shinyApp(ui = ui, server = server)

Answer 1

When you put the data into long format and give each group a group identifier it seems to work. Note that you should be able to change sliderInput back to selectInput - this was one of the entries I toggled during testing, but the choice of UI widget should not matter.
This works -- code can be simplified inside the reactive from here:
library(plotly)
ui <- fluidPage(
sidebarLayout(
sliderInput("Var1",
label = "Variable", #DATA CHOICE 1
min=10, max=100, value=10),
sliderInput("Var2",
label = "Variable2", #DATA CHOICE 2
min=10, max=100, value=10),
),
mainPanel(
plotlyOutput('plot') #Draw figure
)
)
server <- function(input, output) {
out <- reactive({
x1 <- rnorm(input$Var1)
y1 <- seq(1:input$Var1)
x2 <- rnorm(input$Var2)
y2 <- seq(1:input$Var2)
xx <- c(x1,x2)
yy <- c(y1,y2)
gg <- c( rep(1,length(y1)), rep(2,length(y2)) )
df <- data.frame(cbind(xx,yy,gg))
df
})
output$plot <- renderPlotly({
p <- ggplot() +
geom_line(data=out(), aes(x = xx, y = yy, group=gg, colour=gg))
ggplotly(p)
})
}
shinyApp(ui = ui, server = server)