How to save the value of an output to use it in another output?

[deloitte_jogonzalez]

I am calculating something to present it as a table output. But when I try to download, I discovered that I have to calculate everything again to get the same set of data that I am presenting. How I can avoid this?

Beforehand, thank you very much

[andresrcs]

Hi, welcome!

To help us help you, could you please prepare a reproducible example (reprex) illustrating your issue? Please have a look at this guide, to see how to create one for a shiny app

Shiny debugging and reprex guide

Shiny issues can be challenging to resolve relative to other problems with your code or statistical methods. Shiny apps are often large, complex projects with interacting files. When seeking help from others it is considered polite to: First, do your best to work through RStudio's debugging tools to diagnose your issue on your own. Often those shiny logs and tracebacks are useful to others trying to help out. Second, strive to minimize the effort required to replicate your issue. You can do this with a reproducible example ("reprex"). Shiny Debugging Errors in Shiny code can be difficult to track down. If you don't know where your problem is coming from, you can track it down with some o…

[deloitte_jogonzalez]

Hi @andresrcs

Background information
I have this interface

Considerations:
Initially the report tab is empty.

Process Flow:

1. When you select what you want to filter, including the variable slider, then
   you press the "Apply Filters" button and then below of the title "Detail of dataset" will appear a renderTable() with the filtered dataset.
   Also, It'll appear a "Run Analysis" button.
   This execution is using this¬
   output$table1 <- DT::renderDataTable(DT::datatable({

        result <- dataset
   
        if (input$filter_1 != "Todo"){
              result <- result[result$value1 == input$filter_1,]
        }
        if (input$filter_2 != "Todo") {
              result <- result[result$value2 == input$filter_2,]
        }
        if (input$filter_3 != "Todo") {
              result <- result[result$value3 == input$filter_3,]
        }
       result
   
      result
   

}))
2. When you press the "Run Analysis" button. It will take the filtered dataset and procede to run something else.
This execution is using this ¬
observeEvent(input$Run, {
output$table2 <- renderTable({
here I run my analysis and I put the result dataset at the end
})
})

3. Finally, the table with the result will appear in the "Report" tab and also a "Download .csv" using the following code in the ui component ¬
   tabPanel(
   title = 'Report',
   value = "tab2",
   tableOutput('table2'),
   downloadButton("downloadData", "Download (.csv)")
   )

Inconvenient:
When I tried to write my code to download the final report. I realized that I needed to run the analysis again to get the dataset and then be able to download it.

Other issues:
I also realized that I have to run the filtering code to reproduce the same filtered dataset to run my main analysis

[andresrcs]

Could you please read the guide I gave you before and turn this into a proper self contained reproducible example?

In the meanwhile you can consider creating the dataframe globally for each session in your server function, that way you can reference it from any reactive function and you wouldn't have to filter again.

[Maxime_deb]

Hi,

I am pretty sure the answer I received from PJ can help you with this!

shiny: use the same function to render a table and a plot without calling twice the function?

Hello all, It is a bit tricky to explain but let's give it a try. Some of my functions are of the following type: Example_Function <- function (...) { Table = ... print(ggplot) return(Table) } My shiny server.R have the following: output$table <- renderTable({ isolate(inputs) Table = Example_Function(inputs) Table }) output$plot <- renderPlot({ Example_Function(inputs) }) It works but I would like to avoid calling 2 times the function as it takes useless time. I cannot really use a list with the Table and the ggplot in it as this 'Example_Function' is used in many other functions, do.call(Example_Function, ...) etc. Thanks for your help, Regards, Maxime

Regards,

Maxime

[deloitte_jogonzalez]

Thank you @Maxime_deb, I'm gonna check it right now.

[deloitte_jogonzalez]

Excelent @Maxime_deb. That's exactly what I needed