我想使用 R Shiny 绘制一些数据点的空间分布图。当我将不同区域的过滤器添加到 R 脚本中时,它无法在默认地图上显示所有区域的所有数据点。
对于如何改进脚本有什么建议吗?
下面是我的 R 脚本和示例数据:
library(shiny)
library(shinythemes)
library(leaflet)
# generate the data
dat <- data.frame(
region=sample(c("A","B","C"),100,replace=T),
x=rnorm(100, mean=50, sd=10),
y=rnorm(100, mean=40, sd=10)
)
# Define UI for application that draws a histogram
ui <- shinyUI(fluidPage(
theme = shinytheme("united"),
# Application title
titlePanel("Test"),
# Sidebar
sidebarLayout(
sidebarPanel(
selectizeInput(
"regionInput", label=h3("Region"),choices=c("A","B","C"))
),
# Show a plot of the generated distribution
mainPanel(
leafletOutput(outputId = 'map')
)
)
)
)
# Define server logic to map the distribution
server <- shinyServer(function(input, output) {
output$map <- renderLeaflet({
leaflet(dat) %>%
addProviderTiles("Esri.WorldImagery") %>%
addCircleMarkers(color = "blue", radius = 2, stroke = FALSE, fillOpacity = 0.5, lng=dat$x[which(dat$region == input$regionInput)], lat=dat$y[which(dat$region == input$regionInput)])
})
})
# Run the application
shinyApp(ui = ui, server = server)
您需要在下拉列表中添加一个
(All)
元素,并在渲染函数中添加逻辑,如下所示:
library(shiny)
library(shinythemes)
library(leaflet)
# generate the data
dat <- data.frame(
region = sample(c("A", "B", "C"), 100, replace = TRUE),
x = rnorm(100, mean = 50, sd = 10),
y = rnorm(100, mean = 40, sd = 10)
)
# Define UI for application that draws a histogram
ui <- fluidPage(
theme = shinytheme("united"),
# Application title
titlePanel("Test"),
# Sidebar
sidebarLayout(
sidebarPanel(
selectizeInput(
"regionInput",
label = h3("Region"),
choices = c("(All)", "A", "B", "C"))
),
# Show a plot of the generated distribution
mainPanel(
leafletOutput(outputId = "map")
)
)
)
# Define server logic to map the distribution
server <- shinyServer(function(input, output) {
output$map <- renderLeaflet({
if (input$regionInput == "(All)") {
idx <- rep(TRUE, nrow(dat))
} else {
idx <- dat$region == input$regionInput
}
leaflet(dat) %>%
addProviderTiles("Esri.WorldImagery") %>%
addCircleMarkers(color = "blue",
radius = 2,
stroke = FALSE,
fillOpacity = 0.5,
lng = dat[idx, "x"],
lat = dat[idx, "y"])
})
})
# Run the application
shinyApp(ui, server)