I'm not sure I understood the question correctly, but you can call parts of a reactive dataframe by adding the square brackets part after the round ones. df()[ ... , ... ]
For instance if you want to show only the first 3 rows of a file called 'data.csv':
ui <- fluidPage(
tableOutput("data")
)
server <- function(input, output, session) {
fileData <- reactiveFileReader(30000, session, 'data.csv', read.csv2)
output$data <- renderTable({
fileData()[1:3,]
})
}
shinyApp(ui = ui, server = server)
if you would convert it to a normal dataframe there is no point in using reactiveFileReader I guess...
but you could send the data out of the reactive dataframe to the global environment with <<-
For istance, show first 3 rows in panel, save first colum in global environment:
output$data <- renderTable({
send_to_global <<- fileData()[,1]
return(fileData()[1:3,])
})
Hope this is useful