R Language Shiny App Quiz 25

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The post contains a list of R Language Shiny App Quiz Questions with Answers. There are 20 multiple-choice question about shiny app and dashboard. Let us start with the R Language Shiny App Quiz now.

R Language Shiny App Quiz with answers

Online R Language Shiny App Quiz with Answers

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

 
 
 
 
 

2. What is the purpose of plotOutput()?

 
 
 

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

 
 
 

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

 
 
 
 

5. 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?

 
 
 

6. 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?

 
 
 

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

 
 
 

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

 
 
 
 
 

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

 
 

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

 
 
 

11. 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?

 
 
 

12. Which of the following statement will install shiny?

 
 
 
 

13. 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?

 
 
 
 

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

 
 
 
 

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

 
 
 

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

 
 
 
 

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

 
 
 

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

 
 
 
 

19. 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?

 
 
 

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

 
 
 
 

R Language Shiny App Quiz with Answers

  • What is the maximum number of bins for sliderInput()?
  • What is the purpose of the shinyApp() function?
  • What software is most typically used to write and run a Shiny App?
  • Which objects must be created in a Shiny app to create a Shiny application with input and output?
  • Which of these most closely reflects the basic purpose of Shiny?
  • What is the role of the fluidPage() function in a Shiny application?
  • What is the first argument in any input function in Shiny, e.g., sliderInput(), selectInput(), numericInput()?
  • Say you use a function like 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?
  • What is the purpose of plotOutput()?
  • What is the purpose of the renderPlot() function?
  • Which of these are appropriate ways to run a Shiny app?
  • Which of the following are necessary for creating a functioning shiny app?
  • What are the main differences between creating a Shiny Gadget and creating a regular Shiny App?
  • If you want to share flexdashboard with someone, which of these are available options?
  • 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?
  • 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?
  • 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?
  • 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?
  • Which of the following statements will install shiny?
  • All of the styled elements are handled through the server.R.

SPSS and Data Analysis

Lists in R Language

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The post is about Lists in R Language. It is in the form of questions and answers for creating lists, updating and removing the elements of a list, and manipulating the elements of Listsin R Language.

What are Lists in R Language?

Lists in R language are the objects that contain elements of different data types such as strings, numbers, vectors, and other lists inside the list. A list can contain a matrix or a function as its elements. The list is created using the list() function in R. In other words, a list is a generic vector containing other objects. For example, in the code below, the variable $X$ contains copies of three vectors, n, s, b, and a numeric value 3.

n = c(2, 3, 5)
s = c("a", "b", "c", "d")
b = c(TRUE, FALSE, TRUE, TRUE, FALSE, TRUE)

# create an ex that contains copies of n, s, b, and value 3
x = list(n, s, b, 3)

Explain How to Create a List in R Language

Let us create a list that contains strings, numbers, and logical values. for example,

data <- list("Green", "Blue", c(5, 6, 7, 8), TRUE, 17.5, 15:20)
print(data)

The print(data) will result in the following output.

Lists in R Language

How to Access Elements of the Lists in R Language?

To answer this, let us create a list first, that contains a vector, a list, and a matrix.

data <- list(c("Feb","Mar","Apr"), 13.4, matrix(c(3,9,5,1,-2,8), nrow = 2))

Now let us give names to the elements of the list created above and stored in the data variable.

names(data) <- c("Months", "Value", "Matrix")

data

## Output
$Months
[1] "Feb" "Mar" "Apr"

$Value
[1] 13.4

$Matrix
     [,1] [,2] [,3]
[1,]    3    5   -2
[2,]    9    1    8

To access the first element of a list by name or by index, one can type the following command.

# access the first element of the list
data[1]   #or print(data[1])
data$Months

## Output
$Months
[1] "Feb" "Mar" "Apr"

Similarly, to access the third element, use the command

# access the third element of the list
data[3]   #or print(data[3])  #or  data[[3]]
data$Matrix

## Output
$Months
[1] "Feb" "Mar" "Apr"

How Elements of the List are Manipulated in R?

To add an element at the end of the list, use the command

data[4] <- "New List Element(s)"

To remove the element of a list use

# Remove the first element of a list
data[1] <- NULL

To update certain elements of a list

data[2] = "Updated Element"

Statistics and Data Analysts

MCQs Data Visualization in R 24

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The Quiz is about MCQs Data Visualization in R Programming Language. There are 20 multiple-choice questions covering different topics related to R Language Programming. Let us start with the MCQs Data Visualization in R Language now.

MCQs Data Visualization in R Languages
Please go to MCQs Data Visualization in R 24 to view the test

Online MCQs Data Visualization in R Language

  • Which function in ggplot adds a title to the plot?
  • Which function is used to specify appropriate names for both axes in a plot?
  • Which R statement creates a chart object based on the data frame “salesdata”, but allows you to vary the aesthetics from one layer to another?
  • The qplot() function has no defaults, giving you more control over the output.
  • Which R packages will this course use to create data visualizations?
  • Which chart is a type of part of the whole chart?
  • Which ggplot2 function can create a complete plot given the data, mappings, and geom as parameters?
  • Which of the following statements about histograms is true?
  • A pie chart is the same as a —————– in polar coordinates.
  • Which parameter of the qplot() function changes the border color of the bars in a bar chart to blue?
  • How can you improve the smoothness of a histogram?
  • What step must you take before you can add the coord_polar() function to ggplot() to create a pie chart?
  • In a scatter plot, what is the best way to change the color of the points based on a categorical variable?
  • Which plot type helps you visualize time series data?
  • Which functions can you use to change the title of a plot?
  • What can you add to a plot if you want to emphasize important elements, such as outliers or spikes in your data?
  • You want to divide a plot into subplots based on a categorical variable called “quarters”. Which function should you add to ggplot() to do this?
  • What information do you need to provide to create a visualization using the Leaflet library?
  • You added text labels to the data points on your plot, but now the plot looks messy because there are so many of them. What should you do?
  • If you do not specify a theme when creating a plot with ggplot2, which theme does it use by default?

statistics and data analysis