creation of gif in r

Question

I’m trying to create a Plot GIF below:

x<-NULL
y<-NULL
for(i in 1:500){
  y[i]<-sum(rnorm(i))/i
  x[i]<-i
  plot(y~x, type="l")
  abline(y=0)
  Sys.sleep(0.25)
}

Answer 1

There are several ways to produce a gif on R. If you want to transform gif images right on your computer, you will need to imagemagick.

I show here an example using the package magick and the functions image_graph() to save each graph to an object, image_animate() for the animation and image_write() to save the gif.

Saving the Plot of each interaction with the function image_graph():

    library(magick)

    # atenção que pode demorar alguns minutos
    x<-1
    y<-1
    for(i in 1:250){
      y[i]<-sum(rnorm(i))/i
      x[i]<-i
        name <- paste0('fig', i)
        assign(name, image_graph(res = 65))
        plot(y~x, type="l")
        dev.off()
    }

Now that each Plot is saved in a different object (figi), we can gather all in one vector:

    # vetor de nomes
    figs <- paste0('fig', 1:250)

    # unindo os plots
    img <- mget(figs)
    img <- image_join(img)

Creating and saving the gif:

    gif <- image_animate(img, fps = 10, dispose = "previous")

    image_write(gif, "gif.gif")

Reference for more features of the package magick can be found here.

EDIT:

Depending on the number and complexity of the created figures, it is important to remember the available memory:

# remover todos os plots da memória
rm(list = ls()[ls() %in% paste0('fig', 1:250)])