如何在R shiny的特定列后添加空列，并根据用户特定替换值

Question

按钮"DeleteRows,"替换值"如下面的R代码所示;根据代码，上传csv数据后，按钮"SplitColumns"one_answers";DeleteRows"完美地运作。为了使它更有用，我想在用户指定的列之后添加空列(按照SelectInput: labeled: "select column)并替换标记为"的框中的值。输入要替换的值:">

我创建了一个名为"fillvalues"然而，对于这一点，它不起作用，并给了我以下错误:

有人能帮我解决这个问题吗?

误差

警告:sub: object 'df_fill'找不到错误

csv数据

ID  Type   Range
21  A1 B1   100
22  C1 D1   200
23  E1 F1   300

应用程序。R

library(shiny)
library(reshape2)
#source('splitColumn_stack.R')
library(DT)

###function for deleting the rows
splitColumn <- function(data, column_name) {
newColNames <- c("Unmerged_type1", "Unmerged_type2")
newCols <- colsplit(data[[column_name]], " ", newColNames)
after_merge <- cbind(data, newCols)
after_merge[[column_name]] <- NULL
after_merge
}
###_______________________________________________
### function for replacing the empty values
library(tidyr)
fillvalues <- function(columName, value){
df_fill[[columName]] <- sub("^$", value , df_fill[[columName]])
df_fill
}


### use a_splitme.csv for testing this program
ui <- fluidPage(
sidebarLayout(
sidebarPanel(
fileInput("file1", "Choose CSV File", accept = ".csv"),
checkboxInput("header", "Header", TRUE),
actionButton("Splitcolumn", "SplitColumn"),
selectInput(inputId='selectcolumn', label='select column', ''),
actionButton("deleteRows", "Delete Rows"),
textInput("textbox", label="Input the value to replace:"),
actionButton("replacevalues", label = 'Replace values')
),
mainPanel(
DTOutput("table1")
)
)
)
server <- function(session, input, output) {
rv <- reactiveValues(data = NULL)

observeEvent(input$file1, {
file <- input$file1
ext <- tools::file_ext(file$datapath)

req(file)

validate(need(ext == "csv", "Please upload a csv file"))

rv$data <- read.csv(file$datapath, header = input$header)

updateSelectInput(session, 'selectcolumn', 'select column', names(rv$data))

})

observeEvent(input$Splitcolumn, {
rv$data <- splitColumn(rv$data, input$selectcolumn)
})

observeEvent(input$deleteRows,{
if (!is.null(input$table1_rows_selected)) {
rv$data <- rv$data[-as.numeric(input$table1_rows_selected),]
}
})

output$table1 <- renderDT({
rv$data
})
observeEvent(input$replacevalues, {
rv$value <- fillvalues(rv$value, input$selectcolumn)
})
}
shinyApp(ui, server)

Answer 1

无需"replace"任何值，只需插入一个包含用户输入值的新列。

下面是使用tibble包中的add_column()函数的示例。

请注意，这只是一个起点，用户必须输入与表中的行数相对应的正确的值的数量，用逗号分隔。

也没有对输入值的类型进行验证，因此它们都在新列中作为字符结束。

library(shiny)
library(reshape2)
#source('splitColumn_stack.R')
library(DT)
library(tibble)

###function for deleting the rows
splitColumn <- function(data, column_name) {
newColNames <- c("Unmerged_type1", "Unmerged_type2")
newCols <- colsplit(data[[column_name]], " ", newColNames)
after_merge <- cbind(data, newCols)
after_merge[[column_name]] <- NULL
after_merge
}
###_______________________________________________
### function for inserting a new column
fillvalues <- function(data, values, columName){
df_fill <- data
vec <- strsplit(values, ",")[[1]]
df_fill <- tibble::add_column(df_fill, newcolumn = vec, .after = columName)
df_fill
}    
### use a_splitme.csv for testing this program
ui <- fluidPage(
sidebarLayout(
sidebarPanel(
fileInput("file1", "Choose CSV File", accept = ".csv"),
checkboxInput("header", "Header", TRUE),
actionButton("Splitcolumn", "SplitColumn"),
selectInput(inputId='selectcolumn', label='select column', ''),
actionButton("deleteRows", "Delete Rows"),
textInput("textbox", label="Input the value to replace:"),
actionButton("replacevalues", label = 'Replace values')
),
mainPanel(
DTOutput("table1")
)
)
)
server <- function(session, input, output) {
rv <- reactiveValues(data = NULL)
observeEvent(input$file1, {
file <- input$file1
ext <- tools::file_ext(file$datapath)
req(file)
validate(need(ext == "csv", "Please upload a csv file"))
rv$data <- read.csv(file$datapath, header = input$header)
updateSelectInput(session, 'selectcolumn', 'select column', names(rv$data))
})
observeEvent(input$Splitcolumn, {
rv$data <- splitColumn(rv$data, input$selectcolumn)
})
observeEvent(input$deleteRows,{
if (!is.null(input$table1_rows_selected)) {
rv$data <- rv$data[-as.numeric(input$table1_rows_selected),]
}
})
output$table1 <- renderDT({
rv$data
})
observeEvent(input$replacevalues, {
rv$data <- fillvalues(rv$data, input$textbox, input$selectcolumn)
})
}
shinyApp(ui, server)