在R Shiny中如何分离滑块输入值并使用它们进行过滤

Question

In R's shiny package you can have a slider widget using sliderInput that has an upper and lower bound.

I would like to be able to separate the upper and lower bound values and filter a column of data with them, before passing that data to UI.R .

For example:

Server.R

library(shiny)
data <- read.csv('some_data_to_filter.csv')

# Define server logic for slider examples
shinyServer(function(input, output) {

  # Reactive expression to compose a data frame containing all of
  # the values
  sliderValues <- reactive({

    # Compose data frame
    data.frame(
      Name = c("Range"),
      Value = as.character(c(paste(input$range, collapse=' '),)), 
      stringsAsFactors=FALSE)
  }) 

  # Show the values using an HTML table
  output$values <- renderTable({
    sliderValues()
  })
})

UI.R

library(shiny)    
# Define UI for slider demo application
shinyUI(fluidPage(

  #  Application title
  titlePanel("Sliders"),

  sidebarLayout(
    sidebarPanel(      
  # Specification of range within an interval
      sliderInput("range", "Range:",
                  min = 1, max = 1000, value = c(200,500))
),

    # A table summarizing the values entered
    mainPanel(
      tableOutput("values")
    )
  )
))

In the example above I read in the data and I have a slider, but there's no filtering of the data like I'd like there to be.

This was my best attempt to split and filter, but it throws an error:

myrange <- reactive({ data.frame(strsplit(Value = input$slider))})
data <- data[data$colname <= as.numeric(myrange[2]),]
data <- data[data$colname >= as.numeric(myrange[2]),]

Answer 1

If I understand your question right you want to subset the data based on the two limits of the slider input right. If so, use the solution below with sample data

library(shiny)

# Sample Data
area <- seq(from=10,to=100, by=10);peri <- seq(from=2710.1,to=2800.1, by=10)
shape <- seq(from=0.1,to=1, by=0.1);perm <- seq(from=1,to=100, by=10)
my_data <- as.data.frame(cbind(area,peri,shape,perm))

ui = fluidPage(
  sidebarPanel(sliderInput("range", "Select Range",min = 1, max = 10, value = c(2, 5)),width = 3),
  mainPanel(tableOutput("view"))
)

server = function(input, output) {
  output$view <- renderTable({
    test <- my_data[input$range[1]:input$range[2],]
    test},include.rownames=FALSE)
}
runApp(list(ui = ui, server = server))