added two more R examples

R/demo8.R

@@ -0,0 +1,51 @@
+library(shiny)
+library(tidyverse)
+library(ggraph)
+library(tidygraph)
+
+
+
+# Define UI for application
+ui <- fluidPage(
+
+    # Application title
+    titlePanel("Social Network"),
+
+    # Sidebar with a slider input for number of bins 
+    sidebarLayout(
+        sidebarPanel(
+            sliderInput("radius",
+                        "Node radius",
+                        min = 1,
+                        max = 50,
+                        value = 30),
+
+            selectInput("style","Layout",c("dendrogram","stress","circlepack"))
+        ),
+
+        # Show  outputs
+        mainPanel(
+           plotOutput("graphPlot",width = "600px"),
+           textOutput("description")
+        )
+    )
+)
+
+
+server <- function(input, output) {
+
+  # load data
+  graph <- as_tbl_graph(highschool)
+
+  output$graphPlot <- renderPlot({
+
+      ggraph(graph(), layout = "dendrogram") + 
+        geom_edge_link() + 
+        geom_node_circle(aes(r=input$radius/100.0),fill="black")+
+        ggraph::theme_graph()
+
+    })
+}
+
+# Run the application 
+shinyApp(ui = ui, server = server)

R/normal.R

@@ -0,0 +1,80 @@
+library(shiny)
+library(dplyr)
+library(ggplot2)
+
+# Define UI for application that draws a histogram
+ui <- fluidPage(
+
+  # Application title
+  titlePanel("Is this normal?"),
+
+  fluidRow(
+    column(12,
+           numericInput(inputId="n",label = "Sample size",value=100,min=5,max=100),
+           plotOutput(outputId = "result"), 
+           shiny::actionButton(inputId = "yes", label="Yes"),
+           shiny::actionButton(inputId = "no", label="No"),
+           htmlOutput(outputId = "msg")
+    )
+  )
+
+
+)
+
+
+server <- function(input, output) {
+
+
+  values <- reactiveValues(normal = 1, status = "")
+
+  observe({
+    input$yes
+    cat("YES\n")
+    check(TRUE)
+  })
+
+  observe({
+    input$no
+    cat("NO\n")
+    check(FALSE)
+  })
+
+  check <- function(user_choice) {
+    if (user_choice == values$normal) {
+      values$status <- "<p style='color:green;'>CORRECT!</p>"
+    } else {
+      values$status <- "<p style='color:red;'>WRONG!</p>"
+    }
+
+    values$normal <- sample(c(TRUE,FALSE),1)
+
+  }
+
+  output$result <- renderPlot({
+
+
+    if ( values$normal ) {
+      dat<-rnorm(input$n)
+    } else {
+      type = sample(c(1,2,3),1)
+      if (type==1) {
+        dat<-rchisq(input$n,df = 3)-1
+      } else if (type==2) {
+        dat<-runif(input$n,-2,2)
+      } else if (type==3) {
+        dat<-rlogis(input$n)
+      }
+    }
+    dat <- data.frame(dat)
+    names(dat) <- c("x")
+    dat %>% ggplot(aes(x=x))+geom_density(fill="grey")+geom_point(y=0,size=4)
+  })
+
+  output$msg <- renderText({
+    return(values$status)
+  })
+
+}
+
+# Run the application 
+shinyApp(ui = ui, server = server)

challenges/02-graph/app.R

@@ -25,7 +25,7 @@ ui <- fluidPage(
 
         # Show a plot of the generated distribution
         mainPanel(
-           plotOutput("graphPlot"),
+           plotOutput("graphPlot",width = "600px"),
            textOutput("description")
         )
     )