"运行App时如何消除“警告：seq.default中的错误：'from'必须是有限数”？"

Question

I'm running a version of the below reduced code in an App that allows the user to stratify the elements in a large data frame as of a single point-in-time. The user can choose which measure to use for time: Period_1<\/code> or Period_2<\/code> , and which time period to select within each of those 2 time categories. The full App offers the user several more stratification variables, and in the renderTable<\/code> section below there remain vestiges of this broader functionality.

library(shiny)
library(tidyverse)
library(shinyWidgets)

custom_min <- function(x) {if (length(x)>0) min(x, na.rm=TRUE) else Inf}
custom_max <- function(x) {if (length(x)>0) max(x, na.rm=TRUE) else Inf}

ui <-
  fluidPage(
    uiOutput("period"),
    uiOutput("strat_time"),
    tableOutput("stratData"))

server <- function(input, output, session) {
  
  stratData <- reactive({
    data.frame(
      ID = c(1,1,2,2,2,2,3,3,3),
      Period_1 = c("2020-03", "2020-04", "2020-01", "2020-02", "2020-03", "2020-04", "2020-02", "2020-03", "2020-04"),
      Period_2 = c(1, 2, 1, 2, 3, 4, 1, 2, 3),
      Values = c(-5, 25, 35, 45, 55, 87, 10, 20, 30)
    )
  })
  
  output$period <- renderUI({
    radioButtons(
      inputId = 'period',
      label = NULL,
      choiceNames = c('By Period_1','By Period_2'), 
      choiceValues = c('Period_1','Period_2'),
      selected = 'Period_1',
      inline = TRUE
    )
  })
  
  output$strat_time <- renderUI({
    req(input$period)
    chc <- unique(na.omit(stratData()[[input$period]]))
    selectInput(inputId = "strat_time", 
                label = "Specify stratification point-in-time:",
                choices = chc,
                selected = chc[1])
  })
  
  output$stratData <- renderTable({
    qs <- ifelse(is.character(stratData()[[input$period]]), "'", "")
    filter_exp1 <- parse(text=paste0(input$period,  "==", qs,input$strat_time, qs))
    stratData_1 <- reactive({stratData() %>% filter(eval(filter_exp1))}) 
    breaks <- seq(custom_min(stratData_1()[[4]]), 
                  custom_max(stratData_1()[[4]]), 
                  by=10)
    if(max(breaks) < max(stratData_1()[[4]], na.rm=TRUE)){breaks <- c(breaks, max(breaks) + 10)}
    
    tmp <- stratData() %>% 
      filter(eval(filter_exp1)) %>%
      mutate(sumvar = cut(!!sym("Values"), breaks=breaks, include.lowest=TRUE, right = TRUE, dig.lab = 5)) %>% 
      group_by(sumvar) %>% 
      summarise(Count = n(),Values = sum(!!sym("Values"))) %>% 
      complete(sumvar, fill = list(Count = 0,Values = 0)) %>% 
      ungroup %>% 
      mutate(Count_pct = Count/sum(Count)*100, Values_pct = Values/sum(Values)*100) %>% 
      dplyr::select(everything(), Count, Count_pct, Values, Values_pct)
    tmp
  })
  
}

shinyApp(ui, server)

Answer 1

This happen because your function custom_min(stratData_1()[[4]])<\/code> can return non-finite numbers, namely Inf<\/code> , when length(x) > 0<\/code> .

    min <- custom_min(stratData_1()[[4]])
    max <- custom_max(stratData_1()[[4]])
    breaks <- if(any(is.infinite(c(min,max)))) c(0, 10) else seq(min, max, by = 10)