Question

在我的闪亮应用中，我为用户输入的日期范围每列选择创建了动态日期范围ui（input$daterange[i]）。然后，我想将每个input$daterange[i]值传递给变量，检查相应列中的哪些行在用户选择的日期范围内，我将检查结果存储在dt$range_checks[i]中。然后在检查了所有input$daterange[1:i]之后，我将检查结果dt$range_checks[1:i]结合起来找出满足所有检查条件的行，此值将存储在dt$filtered_ind中。因此，我将使用此索引来过滤满足所有日期范围要求的行的数据集。但是，我不知道我是如何做到最后一部分的，我如何结合动态检查来获得最终索引？请在下面找到我的代码：

第1部分 - 生成由用户选择的每个日期列的日期范围：

# generate daterange uis per selected input$datecols
  observeEvent({
    # when a new file uploaded
    input$file
    # when user change selection date column(s)
    input$datecols}, {

    dt$datecols = input$datecols
    dt$datecols_len = length(dt$datecols)

    # render daterange ui(s) per selected datecols
    output$daterangescontrol <- renderUI({

      # when input$datecols is NULL, no daterangecontrol ui
      if ( is.null(dt$datecols) ) { return(NULL) }

      # otherwise
      else {

        # whenever input$datecols change, start/end of daterange ui refresh to original state
        D = dt$data

        output = tagList()

        req(dt$datecols_len > 0)
        for (i in 1:dt$datecols_len) {
          output[[i]]= tagList()
          output[[i]][[1]] = tags$div(id = paste("dateranges_div", i, sep = "_"),
                                      dateRangeInput(paste0("daterange", i),
                                                     paste("Date range of", dt$datecols[[i]]),
                                                     start = min(D[[dt$datecols[[i]]]]),
                                                     end = max(D[[dt$datecols[[i]]]])
                                                    ))
        }

        # return output tagList() with ui elements
        output

      }

    })
  }, ignoreNULL = FALSE)

第2部分：这里是用于分配输入$ daterange数据以过滤相应列的代码：

  observe({

    # loop observeEvent on input$daterange1, input$daterange2... 
    lapply( 1:dt$datecols_len,

            FUN = function(i) {

              # don't call the following unless input$datecols is not of length 0
              req(dt$datecols_len > 0)

              # on change of input$daterange[i]
              observeEvent(input[[paste0("daterange", i)]], {

                # update reactive values to test whether this loop is working
                dt$range[[i]] = input[[paste0("daterange", i)]]

                req(dt$range[[i]])


                # filter dataset with the corresonding date column:
                D = dt$data[dt$cols]
                col = dt$datecols[[i]]
                dt$range_checks[i] = D[[col]] >=  dt$range[[i]][[1]] & D[[col]] <= dt$range[[i]][[2]]

              }) # end of observeEvent
            } 
    ) # end of lapply()

    lapply( dt$range_checks,
            FUN = function(x) {
              # How to write the code to get the following desired result????
              dt$filtered_ind = dt$range_checks[1] & dt$range_checks[2] ... dt$range_checks[i]
            }
          )

  })

如何将变量作为表达式的一部分添加到r中的变量中

0 个答案: