R海拾遗-shiny3

时间:2022-07-25
本文章向大家介绍R海拾遗-shiny3,主要内容包括其使用实例、应用技巧、基本知识点总结和需要注意事项,具有一定的参考价值,需要的朋友可以参考一下。

shiny 学习3

概述

正文

使用R脚本和带入数据

数据集:counties.rds是美国每个县的人口统计数据集,由UScensus2010 收集。需要另外下载 https://shiny.rstudio.com/tutorial/written-tutorial/lesson5/census-app/data/counties.rds 下载后是一个rds文件,需要在之前介绍的app文件夹中建立data文件,然后将数据集移动到data中 脚本:help.R: https://shiny.rstudio.com/tutorial/written-tutorial/lesson5/census-app/helpers.R 下载之后将脚本放入app文件夹中 代码

setwd("D:\360MoveData\Users\cmusunqi\Documents\GitHub\R_and_python\R")
counties <- readRDS("census-app/data/counties.rds")
head(counties)
# 包含州的名字和人口构成

# 安装地图包
# install.packages(c("maps", "mapproj"))
# maps和mapproj是脚本使用到的包
library(maps)
library(mapproj)
# 使用预先写好的脚本绘制地图
source("census-app/helpers.R")
counties <- readRDS("census-app/data/counties.rds")
# 各县的数据绘制成地形图。这里用深绿色表示各县白人居民的比例。
percent_map(counties$white, "darkgreen", "% White")

结果

# 接下来使用shiny控件
library(shiny)
ui <- fluidPage(
  titlePanel("censusVis"),
  
  sidebarLayout(
    sidebarPanel(
      helpText("Create demographic maps with
        information from the 2010 US Census."),
      
      selectInput("var", 
                  label = "Choose a variable to display",
                  choices = c("Percent White", "Percent Black",
                              "Percent Hispanic", "Percent Asian"),
                  selected = "Percent White"),
      
      sliderInput("range", 
                  label = "Range of interest:",
                  min = 0, max = 100, value = c(0, 100))
    ),
    
    mainPanel(plotOutput("map"))
  )
)

# Server
# 通过server代码连接输出字段
server <- function(input, output) {
  # 定义输出图
  output$map <- renderPlot({
    data <- switch(input$var, 
                   "Percent White" = counties$white,
                   "Percent Black" = counties$black,
                   "Percent Hispanic" = counties$hispanic,
                   "Percent Asian" = counties$asian)
    color <- switch(input$var, 
                    "Percent White" = "darkgreen",
                    "Percent Black" = "black",
                    "Percent Hispanic" = "darkorange",
                    "Percent Asian" = "darkviolet")
    
    legend <- switch(input$var, 
                     "Percent White" = "% White",
                     "Percent Black" = "% Black",
                     "Percent Hispanic" = "% Hispanic",
                     "Percent Asian" = "% Asian")
    # 这里是绘图的函数
    percent_map(var = data, color , legend, max =input$range[1] ,input$range[2])
  })}


shinyApp(ui, server)

结果