Server Function
The server function contains the instructions for the reactivity needed for the Shiny app.
The following function takes two arguments: input
and output
. These
objects are created by Shiny when the session begins and passed to the server
function.
input
is used to pass the control values, in this case input$obs
the number
of observations. Notice how it is used to generate random numbers from
a Normal distribution:
server <- function(input, output) {
output$distPlot <- renderPlot({
dist <- rnorm(input$obs)
hist(dist,
col="purple",
xlab="Random values")
})
}
The output
object contains the output objects, in our case the rendered plot.
input
and output
together describe the state of the app.