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add source code to tutorial topics
This commit is contained in:
JJ Allaire
@@ -1,2 +1,60 @@
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The Hello Shiny example is a simple application that generates a random distribution with a configurable number of observations and then plots it. To run the example type:
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<pre><code class="console">> library(shiny)
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> runExample("01_hello")
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</code></pre>
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#### ui.R
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<pre><code class="r">library(shiny)
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# Define UI for application that plots random distributions
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shinyUI(pageWithSidebar(
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# Application title
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headerPanel("Hello Shiny!"),
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# Sidebar with a slider input for number of observations
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sidebarPanel(
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sliderInput("obs",
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"Number of observations:",
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min = 0,
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max = 1000,
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value = 500)
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),
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# Show a plot of the generated distribution
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mainPanel(
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plotOutput("distPlot")
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)
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))
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</code></pre>
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#### server.R
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<pre><code class="r">library(shiny)
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# Define server logic required to generate and plot a random distribution
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shinyServer(function(input, output) {
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# Function that generates a plot of the distribution. The function
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# is wrapped in a call to reactivePlot to indicate that:
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#
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# 1) It is "reactive" and therefore should be automatically
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# re-executed when inputs change
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# 2) Its output type is a plot
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#
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output$distPlot <- reactivePlot(function() {
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# convert string input to an integer
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obs <- as.integer(input$obs)
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# generate an rnorm distribution and plot it
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dist <- rnorm(obs)
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hist(dist)
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})
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})
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</code></pre>
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@@ -1,3 +1,96 @@
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To run the example type:
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<pre><code class="console">> library(shiny)
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> runExample("08_html")
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</code></pre>
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#### www/index.html
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<pre style='color:#000000;background:#ffffff;'><code><span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>html</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>head</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>script src="shared/jquery.js" type="text/javascript"</span><span style='color:#7f0055; '>></span><span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>script</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>script src="shared/shiny.js" type="text/javascript"</span><span style='color:#7f0055; '>></span><span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>script</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>link</span> rel=<span style='color:#2a00ff; '>"stylesheet"</span> type=<span style='color:#2a00ff; '>"text/css"</span> href=<span style='color:#2a00ff; '>"shared/shiny.css"</span><span style='color:#7f0055; '>/></span>
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<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>head</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>body</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>h1</span><span style='color:#7f0055; '>></span>HTML UI<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>h1</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>p</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>label</span><span style='color:#7f0055; '>></span>Distribution type:<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>label</span><span style='color:#7f0055; '>></span><span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>br</span> <span style='color:#7f0055; '>/></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>select</span> name=<span style='color:#2a00ff; '>"dist"</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>option</span> value=<span style='color:#2a00ff; '>"norm"</span><span style='color:#7f0055; '>></span>Normal<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>option</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>option</span> value=<span style='color:#2a00ff; '>"unif"</span><span style='color:#7f0055; '>></span>Uniform<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>option</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>option</span> value=<span style='color:#2a00ff; '>"lnorm"</span><span style='color:#7f0055; '>></span>Log-normal<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>option</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>option</span> value=<span style='color:#2a00ff; '>"exp"</span><span style='color:#7f0055; '>></span>Exponential<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>option</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>select</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>p</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>p</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>label</span><span style='color:#7f0055; '>></span>Number of observations:<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>label</span><span style='color:#7f0055; '>></span><span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>br</span> <span style='color:#7f0055; '>/></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>input</span> type=<span style='color:#2a00ff; '>"number"</span> name=<span style='color:#2a00ff; '>"n"</span> value=<span style='color:#2a00ff; '>"500"</span> min=<span style='color:#2a00ff; '>"1"</span> max=<span style='color:#2a00ff; '>"1000"</span> <span style='color:#7f0055; '>/></span>
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<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>p</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>pre</span> id=<span style='color:#2a00ff; '>"summary"</span> class=<span style='color:#2a00ff; '>"shiny-text-output"</span><span style='color:#7f0055; '>></span><span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>pre</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>div</span> id=<span style='color:#2a00ff; '>"plot"</span> class=<span style='color:#2a00ff; '>"shiny-plot-output"</span>
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style=<span style='color:#2a00ff; '>"</span><span style='color:#7f0055; font-weight:bold; '>width</span>: 100%; <span style='color:#7f0055; font-weight:bold; '>height</span>: 400px<span style='color:#2a00ff; '>"</span><span style='color:#7f0055; '>></span><span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>div</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '><</span><span style='color:#7f0055; font-weight:bold; '>div</span> id=<span style='color:#2a00ff; '>"table"</span> class=<span style='color:#2a00ff; '>"shiny-html-output"</span><span style='color:#7f0055; '>></span><span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>div</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>body</span><span style='color:#7f0055; '>></span>
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<span style='color:#7f0055; '></</span><span style='color:#7f0055; font-weight:bold; '>html</span><span style='color:#7f0055; '>></span>
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</code></pre>
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#### server.R
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<pre><code class="r">library(shiny)
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# Define server logic for random distribution application
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shinyServer(function(input, output) {
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# Reactive function to generate the requested distribution. This is
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# called whenever the inputs change. The output functions defined
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# below then all used the value computed from this function
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data <- reactive(function() {
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dist <- switch(input$dist,
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norm = rnorm,
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unif = runif,
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lnorm = rlnorm,
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exp = rexp,
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rnorm)
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dist(as.integer(input$n))
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})
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# Generate a plot of the data. Also uses the inputs to build the
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# plot label. Note that the dependencies on both the inputs and
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# the data reactive function are both tracked, and all functions
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# are called in the sequence implied by the dependency graph
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output$plot <- reactivePlot(function() {
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dist <- input$dist
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n <- input$n
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hist(data(),
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main=paste('r', dist, '(', n, ')', sep=''))
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})
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# Generate a summary of the data
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output$summary <- reactivePrint(function() {
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summary(data())
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})
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# Generate an HTML table view of the data
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output$table <- reactiveTable(function() {
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data.frame(x=data())
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})
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})
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</code></pre>
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@@ -1,3 +1,82 @@
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To run the example type:
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<pre><code class="console">> library(shiny)
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> runExample("07_widgets")
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</code></pre>
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#### ui.R
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<pre><code class="r">library(shiny)
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# Define UI for dataset viewer application
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shinyUI(pageWithSidebar(
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# Application title.
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headerPanel("More Widgets"),
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# Sidebar with controls to select a dataset and specify the number
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# of observations to view. The helpText function is also used to
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# include clarifying text. Most notably, the inclusion of a
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# submitButton defers the rendering of output until the user
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# explicitly clicks the button (rather than doing it immediately
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# when inputs change). This is useful if the computations required
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# to render output are inordinately time-consuming.
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sidebarPanel(
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selectInput("dataset", "Choose a dataset:",
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choices = c("rock", "pressure", "cars")),
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numericInput("obs", "Number of observations to view:", 10),
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helpText("Note: while the data view will show only the specified",
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"number of observations, the summary will still be based",
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"on the full dataset."),
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submitButton("Update View")
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),
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# Show a summary of the dataset and an HTML table with the requested
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# number of observations. Note the use of the h4 function to provide
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# an additional header above each output section.
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mainPanel(
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h4("Summary"),
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verbatimTextOutput("summary"),
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h4("Observations"),
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tableOutput("view")
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)
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))
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</code></pre>
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#### server.R
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<pre><code class="r">library(shiny)
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library(datasets)
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# Define server logic required to summarize and view the selected dataset
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shinyServer(function(input, output) {
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# Return the requested dataset
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datasetInput <- reactive(function() {
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switch(input$dataset,
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"rock" = rock,
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"pressure" = pressure,
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"cars" = cars)
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})
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# Generate a summary of the dataset
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output$summary <- reactivePrint(function() {
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dataset <- datasetInput()
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summary(dataset)
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})
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# Show the first "n" observations
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output$view <- reactiveTable(function() {
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obs <- as.integer(input$obs)
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head(datasetInput(), n = obs)
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})
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})
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</code></pre>
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@@ -3,3 +3,99 @@
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To run the example type:
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<pre><code class="console">> library(shiny)
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> runExample("03_reactivity")
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</code></pre>
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#### ui.R
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<pre><code class="r">library(shiny)
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# Define UI for dataset viewer application
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shinyUI(pageWithSidebar(
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# Application title
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headerPanel("Reactivity"),
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# Sidebar with controls to provide a caption, select a dataset, and
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# specify the number of observations to view. Note that changes made
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# to the caption in the textInput control are updated in the output
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# area immediately as you type
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sidebarPanel(
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textInput("caption", "Caption:", "Data Summary"),
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selectInput("dataset", "Choose a dataset:",
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choices = c("rock", "pressure", "cars")),
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numericInput("obs", "Number of observations to view:", 10)
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),
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# Show the caption, a summary of the dataset and an HTML table with
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# the requested number of observations
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mainPanel(
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h3(textOutput("caption")),
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verbatimTextOutput("summary"),
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tableOutput("view")
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)
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))
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</code></pre>
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#### server.R
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<pre><code class="r">library(shiny)
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library(datasets)
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# Define server logic required to summarize and view the selected dataset
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shinyServer(function(input, output) {
|
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# By declaring databaseInput as a reactive function we ensure that:
|
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#
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# 1) It is only called when the inputs it depends on changes
|
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# 2) The computation and result are shared by all the callers (it
|
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# only executes a single time)
|
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# 3) When the inputs change and the function is re-executed, the
|
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# new result is compared to the previous result; if the two are
|
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# identical, then the callers are not notified
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#
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datasetInput <- reactive(function() {
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switch(input$dataset,
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"rock" = rock,
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"pressure" = pressure,
|
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"cars" = cars)
|
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})
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# The output$caption is computed based on a reactive function that
|
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# returns input$caption. When the user changes the "caption" field:
|
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#
|
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# 1) This function is automatically called to recompute the output
|
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# 2) The new caption is pushed back to the browser for re-display
|
||||
#
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# Note that because the data-oriented reactive functions below don't
|
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# depend on input$caption, those functions are NOT called when
|
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# input$caption changes.
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output$caption <- reactiveText(function() {
|
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input$caption
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})
|
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|
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# The output$summary depends on the datasetInput reactive function,
|
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# so will be re-executed whenever datasetInput is re-executed
|
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# (i.e. whenever the input$dataset changes)
|
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output$summary <- reactivePrint(function() {
|
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dataset <- datasetInput()
|
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summary(dataset)
|
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})
|
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|
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# The output$view depends on both the databaseInput reactive function
|
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# and input$obs, so will be re-executed whenever input$dataset or
|
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# input$obs is changed.
|
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output$view <- reactiveTable(function() {
|
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obs <- as.integer(input$obs)
|
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head(datasetInput(), n = obs)
|
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})
|
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})
|
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</code></pre>
|
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@@ -1,3 +1,69 @@
|
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|
||||
|
||||
|
||||
To run the example type:
|
||||
|
||||
<pre><code class="console">> library(shiny)
|
||||
> runExample("02_text")
|
||||
</code></pre>
|
||||
|
||||
#### ui.R
|
||||
|
||||
<pre><code class="r">library(shiny)
|
||||
|
||||
# Define UI for dataset viewer application
|
||||
shinyUI(pageWithSidebar(
|
||||
|
||||
# Application title
|
||||
headerPanel("Shiny Text"),
|
||||
|
||||
# Sidebar with controls to select a dataset and specify the number
|
||||
# of observations to view
|
||||
sidebarPanel(
|
||||
selectInput("dataset", "Choose a dataset:",
|
||||
choices = c("rock", "pressure", "cars")),
|
||||
|
||||
numericInput("obs", "Number of observations to view:", 10)
|
||||
),
|
||||
|
||||
# Show a summary of the dataset and an HTML table with the requested
|
||||
# number of observations
|
||||
mainPanel(
|
||||
verbatimTextOutput("summary"),
|
||||
|
||||
tableOutput("view")
|
||||
)
|
||||
))
|
||||
</code></pre>
|
||||
|
||||
#### server.R
|
||||
|
||||
<pre><code class="r">library(shiny)
|
||||
library(datasets)
|
||||
|
||||
# Define server logic required to summarize and view the selected dataset
|
||||
shinyServer(function(input, output) {
|
||||
|
||||
# Return the requested dataset
|
||||
datasetInput <- reactive(function() {
|
||||
switch(input$dataset,
|
||||
"rock" = rock,
|
||||
"pressure" = pressure,
|
||||
"cars" = cars)
|
||||
})
|
||||
|
||||
# Generate a summary of the dataset
|
||||
output$summary <- reactivePrint(function() {
|
||||
dataset <- datasetInput()
|
||||
summary(dataset)
|
||||
})
|
||||
|
||||
# Show the first "n" observations
|
||||
output$view <- reactiveTable(function() {
|
||||
obs <- as.integer(input$obs)
|
||||
head(datasetInput(), n = obs)
|
||||
})
|
||||
})
|
||||
</code></pre>
|
||||
|
||||
|
||||
|
||||
@@ -1,4 +1,25 @@
|
||||
|
||||
|
||||
### Sliders
|
||||
## (Under Construction)
|
||||
|
||||
To run the example type:
|
||||
|
||||
<pre><code class="console">> library(shiny)
|
||||
> runExample("05_sliders")
|
||||
</code></pre>
|
||||
|
||||
#### ui.R
|
||||
|
||||
<pre><code class="r">library(shiny)
|
||||
|
||||
|
||||
</code></pre>
|
||||
|
||||
#### server.R
|
||||
|
||||
<pre><code class="r">library(shiny)
|
||||
|
||||
|
||||
</code></pre>
|
||||
|
||||
|
||||
|
||||
@@ -2,3 +2,93 @@
|
||||
|
||||
|
||||
|
||||
To run the example type:
|
||||
|
||||
<pre><code class="console">> library(shiny)
|
||||
> runExample("06_tabsets")
|
||||
</code></pre>
|
||||
|
||||
#### ui.R
|
||||
|
||||
<pre><code class="r">library(shiny)
|
||||
|
||||
# Define UI for random distribution application
|
||||
shinyUI(pageWithSidebar(
|
||||
|
||||
# Application title
|
||||
headerPanel("Tabsets"),
|
||||
|
||||
# Sidebar with controls to select the random distribution type
|
||||
# and number of observations to generate. Note the use of the br()
|
||||
# element to introduce extra vertical spacing
|
||||
sidebarPanel(
|
||||
radioButtons("dist", "Distribution type:",
|
||||
list("Normal" = "norm",
|
||||
"Uniform" = "unif",
|
||||
"Log-normal" = "lnorm",
|
||||
"Exponential" = "exp")),
|
||||
br(),
|
||||
|
||||
sliderInput("n",
|
||||
"Number of observations:",
|
||||
value = 500,
|
||||
min = 1,
|
||||
max = 1000)
|
||||
),
|
||||
|
||||
# Show a tabset that includes a plot, summary, and table view
|
||||
# of the generated distribution
|
||||
mainPanel(
|
||||
tabsetPanel(
|
||||
tabPanel("Plot", plotOutput("plot")),
|
||||
tabPanel("Summary", verbatimTextOutput("summary")),
|
||||
tabPanel("Table", tableOutput("table"))
|
||||
)
|
||||
)
|
||||
))
|
||||
</code></pre>
|
||||
|
||||
#### server.R
|
||||
|
||||
<pre><code class="r">library(shiny)
|
||||
|
||||
# Define server logic for random distribution application
|
||||
shinyServer(function(input, output) {
|
||||
|
||||
# Reactive function to generate the requested distribution. This is
|
||||
# called whenever the inputs change. The output functions defined
|
||||
# below then all use the value computed from this function
|
||||
data <- reactive(function() {
|
||||
dist <- switch(input$dist,
|
||||
norm = rnorm,
|
||||
unif = runif,
|
||||
lnorm = rlnorm,
|
||||
exp = rexp,
|
||||
rnorm)
|
||||
|
||||
dist(as.integer(input$n))
|
||||
})
|
||||
|
||||
# Generate a plot of the data. Also uses the inputs to build the
|
||||
# plot label. Note that the dependencies on both the inputs and
|
||||
# the data reactive function are both tracked, and all functions
|
||||
# are called in the sequence implied by the dependency graph
|
||||
output$plot <- reactivePlot(function() {
|
||||
dist <- input$dist
|
||||
n <- input$n
|
||||
|
||||
hist(data(),
|
||||
main=paste('r', dist, '(', n, ')', sep=''))
|
||||
})
|
||||
|
||||
# Generate a summary of the data
|
||||
output$summary <- reactivePrint(function() {
|
||||
summary(data())
|
||||
})
|
||||
|
||||
# Generate an HTML table view of the data
|
||||
output$table <- reactiveTable(function() {
|
||||
data.frame(x=data())
|
||||
})
|
||||
})
|
||||
</code></pre>
|
||||
|
||||
@@ -17,6 +17,9 @@ title: "Tutorial: Building 'shiny' Web Applications with R"
|
||||
.responsive-image {
|
||||
max-width: 100%;
|
||||
}
|
||||
.console {
|
||||
color: blue;
|
||||
}
|
||||
|
||||
</style>
|
||||
<link href="bootstrap/css/bootstrap-responsive.min.css" rel="stylesheet">
|
||||
|
||||
Reference in New Issue
Block a user