如何在R中使用Leaflet和shiny制作滑块输入？

Question

我有两个数据框，如下所示。为了简单起见，我只放了部分数据：

**order**
Location     Order_count    Longitude   Latitude
New York      12            74.0060     40.7128
San Francisco 7             122.4194    37.7749
Miami         13            80.1918     25.7617
Texas         20            99.9018     31.9686
Dallas        1             96.7970     32.7767
Mary          0             27.6648     81.5158
Whitney       9             32.3182     86.9023

**arrivals**
Cust_id  Arrival_time   Location
1         3             New York
2         18            Miami
3         20            Texas
4          1            New York
5          0            Dallas
6         18            Miami
7         20            Dallas
8          1            New York

1. 首先，我使用订单数据框中的经度和纬度符号来映射传单上的位置。

2. 然后我放置了一个选择到达时间的选择滑块。根据所选时间，该位置（地图上）的客户数量应该发生变化。该地图还显示了该特定位置所有时间段内的总到达人数。例如，如果我选择 Arrival_time=1，如果我在地图上单击纽约，它应该显示：
   “纽约”，

   “所选时间的顾客数量：2”，

   “顾客总数：3”。

我用以下方式编码：

**ui**
shinyUI(fluidpage(
  titlePanel("Time"),
  sidebarLayout(
    sidebarPanel(
      sliderInput("time", "Hours selected ", min=0, max=24, value=12)
    ), 
    
    mainPanel()),
  leafletOutput("mymap", height = "900", width = "900")))

**server**


shinyServer(function(input, output){
  
  data_input <- reactive({arrivals%>% 
      filter(Arrival_time== input$time) %>% 
      group_by(Location) %>% count()
  })
  
  output$mymap <- renderLeaflet({
    leaflet(data=order) %>% addTiles() %>% 
      
      addMarkers(~Longitude, ~Latitude, popup = paste(order$Location,
      "Total arrivals for the selected time: ", arrivals$data_input," 
       order$Order_count))
  })})

地图不会随着滑块提供的输入而改变。我不知道我哪里做错了。

Answer 1

将

arrivals$data_input

替换为

data_input()$n

编辑：根据我们的评论，您最初的问题看起来更像是合并不同的数据集

library(shiny)
library(leaflet)
library(dplyr)

order <- data.frame(
  Location = c('New York', 'San Francisco', 'Miami', 'Texas', 'Dallas', 'Mary', 'Whitney'),
  Order_count = c(12, 7, 13, 20, 1, 0 ,9),   
  Longitude = c(-74.0060, -122.4194, -80.1918, -99.9018, -96.7970, -81.5158, -86.9023),
  Latitude = c(40.7128, 37.7749, 25.7617, 31.9686, 32.7767, 27.6648, 32.3182)
)

arrivals = data.frame(
  Cust_id  = c(1,2,3,4,5,6,7,8),
  Arrival_time = c(3,18,20,1,0,18,20,1),
  Location = c('New York', 'Miami', 'Texas', 'New York', 'Dallas', 'Miami', 'Dallas', 'New York')
)


# Make a dataframe containing needed variables by merging data
join_data <- order %>%
  inner_join(arrivals %>% 
              group_by(Location, Arrival_time) %>% 
              summarise(number_of_customer = n()),
            by = "Location") %>%
  left_join(arrivals %>% 
              group_by(Location) %>% 
              summarise(total_number_of_customer = n()),
            by = "Location")

ui <- shinyUI(fixedPage(
  titlePanel("Time"),
  sidebarLayout(
    sidebarPanel(
      sliderInput("time", "Hours selected ", min=0, max=24, value=1)
    ), 
    
    mainPanel()),
  leafletOutput("mymap", height = "900", width = "900")))



server <- shinyServer(function(input, output, session){
  
  data_input <- reactive({
    join_data %>%
      filter(Arrival_time==input$time)
  })
  
  output$mymap <- renderLeaflet({
    leaflet(data=order) %>% 
      addTiles() %>% 
      addMarkers(
        ~Longitude, 
        ~Latitude, 
        popup = paste(
          order$Location, "<br>",
          "Number of customers for the selected time ", data_input()$number_of_customer," 
          <br>","Total number of customers: ", data_input()$total_number_of_customer))
  })})

shinyApp(ui, server)