我希望能够将反应传递data.table给我的 Rmarkdown 文档，该文档将对表格进行排序并打印顶部（例如 5 个）排序条目。
我一直在遇到“错误：x 必须是 data.frame 或 data.table” setorderv。我怀疑反应是扰乱is.data.table检查。
如何简单地将数据副本传递给 Rmd 文档？并删除反应性包装？
这是一个从反应性和 downloadHandler 库存示例拼凑而成的简化示例。我在 SO上查看了这个，它建议使用观察，但我不知道如何实现这个。谢谢我感谢一些帮助。
RMARKDOWN - SOtestreport.Rmd
---
title: "Top in Segment Report"
output: html_document
params:
n: 5
dt: NA
top.field: NA
---
```{r setup, echo = FALSE}
library(data.table)
library(knitr) # for kable
```
Data report as at: `r format(Sys.time(), "%a %b %d %Y %X")`
```{r, echo = FALSE}
table.str <- paste0("Showing Top ", params$n ," tables for these fields: ",
params$top.field)
# is this the best way of having dynamic labels?
```
`r table.str`
```{r, echo = FALSE}
# tried this
# test.dt <- copy(dt)
# normally a function GenerateTopTable with limit sort field etc.
setorderv(dt, params$top.field, -1) # -1 is descending. THIS IS WHERE IT CRASHES
out <- dt[1:params$n,]
```
```{r toptable, echo = FALSE}
kable(out, digits = 3)
```
应用程序.R
# SO test report
# mini example based on https://shiny.rstudio.com/gallery/reactivity.html
library(shiny)
library(datasets)
server <- function(input, output) {
datasetInput <- reactive({
switch(input$dataset,
"rock" = rock,
"pressure" = pressure,
"cars" = cars)
})
output$caption <- renderText({
input$caption
})
output$summary <- renderPrint({
dataset <- datasetInput()
summary(dataset)
})
output$view <- renderTable({
head(datasetInput(), n = input$obs)
})
# PROBLEM BIT WHERE I AM ADDING ON GALLERY EXAMPLE
# handler from https://stackoverflow.com/questions/37347463/generate-report-with-shiny-app-and
output$topreport <- downloadHandler(
filename = "topreport.html",
content = function(file) {
# Copy the report file to a temporary directory before processing it, in
# case we don't have write permissions to the current working dir (which
# can happen when deployed).
tempReport <- file.path(tempdir(), "SOtestreport.Rmd")
file.copy("SOtestreport.Rmd", tempReport, overwrite = TRUE)
# Set up parameters to pass to Rmd document
# TRIED THIS TOO
# my.dt <- as.data.table(datasetInput())
my.dt <- datasetInput()
my.params <- list(n = input$obs,
dt = my.dt,
top.field = names(my.dt)[1])
rmarkdown::render(tempReport, output_file = file,
params = my.params,
envir = new.env(parent = globalenv())
)
}
)
