Subset dataset based on date inputs which should include NAs as choices

I have the shiny app below in which the dataset that is subseted by min and max date. In my dates I have NAs values which I want to include as choices in my selectInput(). But then I cannot make the subset work.

basically there should be 4 cases. one that no NA is selected,one that both are NA,one that only min is NA and one that only max is NA

library(shiny)
library(DT)

# Creating a sample dataframe
dates <- as.Date(c("2023-01-01", "2023-02-01", NA, "2023-04-01", "2023-05-01"))
names <- c("Alice", "Bob", "Charlie", "David", "Eve")

# Combine them into a dataframe
df <- data.frame(Date = dates, Name = names)

# Generate unique dates sorted in ascending order, including NA
unique_dates <- sort(unique(df$Date), na.last = TRUE)

# Creating a Shiny app
ui <- fluidPage(
  titlePanel("Subset Data by Date Range"),
  sidebarLayout(
    sidebarPanel(
      selectInput("start_date", "Start Date", choices = unique_dates, selected = unique_dates[1]),
      selectInput("end_date", "End Date", choices = unique_dates, selected = unique_dates[length(unique_dates)])
    ),
    mainPanel(
      dataTableOutput("table")
    )
  )
)

server <- function(input, output) {
  output$table <- renderDataTable({
    # Subset the dataframe based on the selected date range
    subset_df <- subset(df, Date >= input$start_date & Date <= input$end_date)
    datatable(subset_df)
  })
}

shinyApp(ui = ui, server = server)

>Solution :

You can do:

  output$table <- renderDataTable({
    # Subset the dataframe based on the selected date range
    if (input$start_date  == "NA" & input$end_date == "NA") {
      subset_df <- subset(df, is.na(Date))
    } else if (input$start_date == "NA") {
      subset_df <- subset(df, is.na(Date) | Date <= input$end_date)
    } else if (input$end_date == "NA") {
      subset_df <- subset(df, Date >= input$start_date | is.na(Date))
    } else {
      subset_df <- subset(df, Date >= input$start_date & Date <= input$end_date)
    }
    datatable(subset_df)
  })

Values in selectInput are strings.

Have a look at shiny::dateRangeInput, it might be more convenient to use.