A Shiny app to understand the `saturation` and `value` parameters in the rainbow() function

shiny_rainbow.R

library(shiny)

# Define the UI
ui <- fluidPage(
  titlePanel("Rainbow Color Palette"),
  sidebarLayout(
    sidebarPanel(
      sliderInput("s_value", "Saturation (s):", min = 0, max = 1, value = 1, step = 0.01),
      sliderInput("v_value", "Value (v):", min = 0, max = 1, value = 1, step = 0.01)
    ),
    mainPanel(
      plotOutput("rainbow_plot")
    )
  )
)

# Define the server
server <- function(input, output) {
  output$rainbow_plot <- renderPlot({
    s <- input$s_value
    v <- input$v_value
    rainbow_colors <- rainbow(12, s = s, v = v)
    
    # Plot the colors
    barplot(rep(1, 12), col = rainbow_colors, border = NA, space = 0)
  })
}

# Run the Shiny app
shinyApp(ui = ui, server = server)