Structure and Syntax in RShiny - Answer Key

Exercise 1

After browsing the gallery of Shiny Apps that have been made by others, what apps do you think you could develop to analyze your own data?

This is a very open-ended question, but some potential ideas could be:

• Running QC analyses on a dataset where you are determining thresholds
• Reading in standardized data to create a report
• Creating a toy example for how a statistical approach works

Exercise 2

1. Name the three parts of an RShiny app and give a brief explanation of each part.

2. In the basic app that we created in this lesson:

# User Interface
ui <- fluidPage(
    # The input text box
    textInput(inputId = "input_text", 
              label = "My input text"),
    # The output text
    textOutput(outputId = "output_text")
)

# Server
server <- function(input, output){
    # Render the text
    output$output_text <- renderText({
        input$input_text
    })
}

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

Describe what information input$input_text and output$output_text holds.

input$input_text is a character string that holds the text entered by the user in the textbox of the RShiny app and output$output_text holds the text that will be returned to the UI as output, after it is rendered by the server.