Shiny with tidyverse

.data[[input$var]]

app.R
data_masking.R

library(shiny)
library(magrittr)
library(ggplot2)

iris_categories <- colnames(dplyr::select(iris, -Species))


ui <- fluidPage(
  titlePanel("Shiny with tidyverse"),
  sidebarLayout(
    sidebarPanel(
       selectInput(inputId = "x_attribute", 
                  label   = "select attribute for x axis", 
                  choices = iris_categories),
       selectInput(inputId  = "y_attribute", 
                   label    = "select attribute for y axis",
                   choices  = iris_categories, 
                   selected = iris_categories[2]),
       textInput(inputId = "plot_name", 
                 label = "Enter plot name"),
       radioButtons(inputId = "radio_colour", 
                    label   = "select point colour",
                    choices = c("blue", "red", "black")),
       actionButton("browser", "browser")
    ),
    mainPanel(
      tabsetPanel(
        tabPanel("base R",
                    plotOutput(outputId = "base_R_iris_plot", width = "400px")
        ),
        tabPanel("ggplot",
                 plotOutput(outputId = "ggplot_iris", width = "400px")
        ),
        tabPanel("ggplot fixed",
                 plotOutput(outputId = "ggplot_iris_fixed_axes", width = "400px")
        ),
        tabPanel("message",
                 br(),
                 p(code(".data[[input$var]]"))
        )
      )
    )
  )
)
  
server <- function(input, output, session) {
  
  output$base_R_iris_plot <- renderPlot({
    
    plot(x = iris[,input$x_attribute],
         y = iris[,input$y_attribute],
         main = input$plot_name,
         col  = input$radio_colour,
         xlab = input$x_attribute,
         ylab = input$y_attribute)
  })
  
  output$ggplot_iris <- renderPlot({

      iris %>%
        ggplot(aes(x = .data[[input$x_attribute]],
                   y = .data[[input$y_attribute]])) +
          geom_point(colour = input$radio_colour) +
          ggtitle(input$plot_name)

  })

  output$ggplot_iris_fixed_axes <- renderPlot({
    
    iris %>%
      ggplot(aes(x = Sepal.Length,
                 y = Sepal.Width)) +
      geom_point(colour = input$radio_colour) +
      ggtitle(input$plot_name)
    
  })
  
  observeEvent(input$browser, {
    
    browser()
    
  })
  
}

shinyApp(ui, server)

library(tidyverse)

# base R
iris[iris$Sepal.Length > 7 & iris$Petal.Width < 2, ]

# tidyverse
iris %>%
  filter(Sepal.Length > 7 & Petal.Width < 2)

# data masking -> minimises repetition
 
#===========================
var1 <- "Sepal.Length"
var2 <- "Petal.Width"

# base R
iris[iris$var1 > 7 & iris$var2 < 2, ]

iris[iris[[var1]] > 7 & iris[[var2]] < 2, ]


# tidyverse
iris %>%
  filter(var1 > 7 & var2 < 2)

iris %>%
  filter(.data[[var1]] > 7 & .data[[var2]] < 2)