基于用户输入shiny R的动态图像输出

library(shiny)
library(ggplot2)

# 定义UI界面
ui <- fluidPage(
  titlePanel("动态图像输出示例"),
  sidebarLayout(
    sidebarPanel(
      sliderInput("n_points", "点的数量", min = 10, max = 100, value = 50),
      selectInput("plot_type", "图像类型", choices = c("散点图", "折线图", "柱状图"), selected = "散点图")
    ),
    mainPanel(
      plotOutput("plot")
    )
  )
)

# 定义服务器逻辑
server <- function(input, output) {
  output$plot <- renderPlot({
    # 根据用户输入生成动态图像
    if (input$plot_type == "散点图") {
      data <- data.frame(x = rnorm(input$n_points), y = rnorm(input$n_points))
      ggplot(data, aes(x, y)) + geom_point()
    } else if (input$plot_type == "折线图") {
      data <- data.frame(x = seq(1, input$n_points), y = cumsum(rnorm(input$n_points)))
      ggplot(data, aes(x, y)) + geom_line()
    } else if (input$plot_type == "柱状图") {
      data <- data.frame(category = letters[1:input$n_points], value = rnorm(input$n_points))
      ggplot(data, aes(category, value)) + geom_bar(stat = "identity")
    }
  })
}

# 运行Shiny应用程序
shinyApp(ui, server)