Hello,

I am working on my project in RStudio using Rmarkdown and I got the following error:
Error in FUN(X[[i]], ...) : object 'descr' not found
A due date will be today. Please help!
Here is the code:

# First save the results
dataset_stats_by_Grade <- by(data = dataset, INDICES = dataset$Grade, 
                    FUN = descr, stats = c("mean", "sd", "min", "med", "max"),transpose = TRUE)

# Then use view(), like so:
View(dataset_stats_by_Grade, method = "pander", style = "rmarkdown")
When I run, I found the following error:
Error in FUN(X[[i]], ...) : object 'descr' not found 

Thanks!!

When trying to clone on Windows I receive the following error:

$ git clone https://github.com/rstudio/ShinyDeveloperConference.git
Cloning into 'ShinyDeveloperConference'...
remote: Counting objects: 411, done.
remote: Total 411 (delta 0), reused 0 (delta 0), pack-reused 411
Receiving objects: 100% (411/411), 16.25 MiB | 973.00 KiB/s, done.
Resolving deltas: 100% (43/43), done.
Checking connectivity... done.
fatal: cannot create directory at 'Modules/Exercise-1/solution': Invalid argument*
warning: Clone succeeded, but checkout failed.
You can inspect what was checked out with 'git status'
and retry the checkout with 'git checkout -f HEAD'

We can't have folder names with * on it.

deleted

Is there a reason that the following doesn't demonstrate a more efficient solution?

  rv <- reactiveValues(points = cars)
  
  # Same as Solution_05a.R, but instead of keeping
  # track of the single most recent point, we accumulate
  # all previous points using rbind().
  observeEvent(input$click, {
    if (!is.null(input$click)) {
      thisPoint <- data.frame(
        speed = input$click$x,
        dist = input$click$y
      )
      rv$points <- rbind(rv$points, thisPoint)
    }
  })
  
  output$plot <- renderPlot({
    df <- rv$points
    plot(df, pch = 19)
    
    model <- lm(dist ~ speed, df)
    abline(model)
  })
}

As Joe Cheng does, I'd like to recognize that while rbind works fairly quickly usually, it seems like this demonstrates how things could be done slightly more efficiently in general

Slide 17 (showing the graph of how reactivity works) that is present in the recording1 is missing in ShinyDeveloperConference/Reactivity/slides.Rmd

(On a related note, slides in github differ from slides in the recording.)

[1] https://www.rstudio.com/resources/webinars/shiny-developer-conference/