我正在尝试使用r显示传单Map（我不能使用shinyapp软件包）。我想在传单标题（或Map中的任何地方）中显示选定点的列平均值，如下图所示：

这是我的尝试：

library(dplyr)
library(leaflet) 
library(DT)
library(crosstalk)

data_2 <- data.frame(ID=c(1:8),
                 Name1 = c("A", "A", "A", "C", "B", "B", "A", "B"),
                 Name2 = c("a", "b", "b", "a", "b", "a", "b", "c"),
                 Value1 = c(12,43,54,34,23,77,44,22),
                 Value2 = c(6,5,2,7,5,6,4,3),
                 Lat = c(51.1, 51.6, 57.3, 52.4, 56.3, 54.3, 60.4, 49.2),
                 Lon = c(5, -3, -2, -1, 4, 3, -5, 0))
data_2<-data_2 %>%
  mutate(
lab_DB = case_when(
  Name1 == unique(data_2$Name1)[1]  ~ "blue",
  Name1 == unique(data_2$Name1)[2]  ~ "green",
  Name1 == unique(data_2$Name1)[3]  ~  "red"

    )
  )
data_2$ID <- as.character(data_2$ID)
sdf <- SharedData$new(data_2, ~data_2$ID)
ltlf5<- leaflet(sdf) %>% 
  #addProviderTiles(providers$CartoDB.Positron) %>%
  addTiles() %>%
  addCircleMarkers(
               lng = ~Lat,
               lat = ~Lon,
               group = ~Name1,popup = ~paste(Name1, '   <br/>  ',
                                                Name2,'   <br/>  ' ),
               color =~lab_DB ,
               radius = 3
 )   %>%
 addLayersControl(

overlayGroups = c('A','B','C')
,options = layersControlOptions(collapsed = FALSE)
  ) %>%
  addLegend(
position = 'bottomleft',
labels = c('Group A','Group B','Group C'),
colors = c("blue","red", "green"),
title = "number of observation"
  ) 
bscols(ltlf5 ,
datatable(sdf , width = "100%",editable=TRUE,caption = paste("mean of Value1:",mean(sdf$data()$Value1)))
)

但不幸的是，它显示的是选定点的“value1”列的平均值，而不是“value1”列的平均值。那么怎么做呢？