R Language Quiz

1. Say you use a function  sliderInput to have the user input some information into a Shiny application. You assign the inputId to “my_input”. How do you call that input in the server function?

2. What is the purpose of the shinyApp() function?

3. All of the styled elements are handled through server.R.

4. Suppose, you are writing a Shiny app and want to display a table for a data frame or tibble in the user interface of your Shiny app. The only lines you have written in your code so far are:

my_dat<-read_csv("my_dat.csv")
ui<-fluidPage(tableOutput("table1"))
server<-function(input,output){
}
Which of the following lines of code could you put inside the brackets of the server function to create a table of the data frame?

5. Which of the following are necessary for creating a functioning shiny app?

6. Which of these are appropriate ways to run a Shiny app?

7. What is the first argument in any input function in Shiny, e.g., sliderInput(), selectInput(), numericInput()?

8. What are the main differences between creating a Shiny Gadget and creating a regular Shiny App?

9. What is the purpose of plotOutput()?

10. Suppose, you are writing a Shiny app and want a user to be able to input text into a textbox, assigning the input to an input slot named “user_name”. You want the textbox to be automatically populated with the character string “Your name here”, which the user can overwrite. Which is the correct code?

11. Which objects must be created in a Shiny app to create a Shiny application with input and output?

12. What is the role of the fluidPage() function in a Shiny application?

13. What is the purpose of the renderPlot() function?

14. What software is most typically used to write and run a Shiny App?

15. What is the maximum number of bins for sliderInput()?

16. Suppose, you are writing a Shiny app and want to create a dropdown menu that allows users to select from a set of options, which you are going to use to filter results in a Shiny app. You want users to be able to select from the values, “Company A”, “Company B”, and “Company C”. You want to assign this to the “company” input slot. Which is the correct code?

17. Which of these most closely reflects the basic purpose of Shiny?

18. Which of the following statement will install shiny?

19. Suppose, you are writing a Shiny app and want users to be able to move a slider to select a single value between 1 and 5. The slider will start at 3. You want the value selected on the slider to be assigned to the input slot “slider_value.” Which of these is the correct code?

20. If you want to share flexdashboard with someone, which of these are available options?