[Data Mining with R] Shiny Apps / Plot Output

[ui.R]

library(shiny);

shinyUI(fluidPage(
  titlePanel("Plot Output Example - by cinema4dr12"),
  
  sidebarLayout(
    sidebarPanel(      
      selectInput("var1",
                  label = "Choose first variable",
                  choices = c("mpg", "cyl", "disp", "hp", "drat", "wt", "qsec", "vs", "am", "gear", "carb"),
                  selected = "mpg"
      ),
      selectInput("var2",
                  label = "Choose second variable",
                  choices = c("mpg", "cyl", "disp", "hp", "drat", "wt", "qsec", "vs", "am", "gear", "carb"),
                  selected = "mpg"
      )
    ),
    
    mainPanel(
      plotOutput("myPlot")
    )
  )
))

[server.R]

library(shiny);

shinyServer(
  function(input, output){
    
    output$myPlot = renderPlot({
      x = input$var1;
      y = input$var2;
      
      switch(x,
        "mpg" = { dataX = mtcars$mpg; xlabel = "mpg"; },
        "cyl" = { dataX = mtcars$cyl; xlabel = "cyl"; },
        "disp" = { dataX = mtcars$disp; xlabel = "disp"; },
        "hp" = { dataX = mtcars$hp; xlabel = "hp"; },
        "drat" = { dataX = mtcars$drat; xlabel = "drat"; },
        "wt" = { dataX = mtcars$wt; xlabel = "wt"; },
        "qsec" = { dataX = mtcars$qsec; xlabel = "qsec"; },
        "vs" = { dataX = mtcars$vs; xlabel = "vs"; },
        "am" = { dataX = mtcars$am; xlabel = "am"; },
        "gear" = { dataX = mtcars$gear; xlabel = "gear"; },
        "carb" = { dataX = mtcars$carb; xlabel = "carb"; }
      );
      
      switch(y,
        "mpg" = { dataY = mtcars$mpg; ylabel = "mpg"; },
        "cyl" = { dataY = mtcars$cyl; ylabel = "cyl"; },
        "disp" = { dataY = mtcars$disp; ylabel = "disp"; },
        "hp" = { dataY = mtcars$hp; ylabel = "hp"; },
        "drat" = { dataY = mtcars$drat; ylabel = "drat"; },
        "wt" = { dataY = mtcars$wt; ylabel = "wt"; },
        "qsec" = { dataY = mtcars$qsec; ylabel = "qsec"; },
        "vs" = { dataY = mtcars$vs; ylabel = "vs"; },
        "am" = { dataY = mtcars$am; ylabel = "am"; },
        "gear" = { dataY = mtcars$gear; ylabel = "gear"; },
        "carb" = { dataY = mtcars$carb; ylabel = "carb"; }
      );
      
      main = paste("Plot between", xlabel);
      main = paste(main, " & ");
      main = paste(main, ylabel);
      plot(dataX, dataY, main = main, xlab = xlabel, ylab = ylabel);
      
    })
  }
)

[Results]