library(ellmer)Capabilities of Large Language Models
Text Analysis with large language models
3th June 2025
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R Shiny
- R Shiny makes it easier for R users to build and share interactive web-based data applications
- See more at Shiny course, Shiny tutorial, or Mastering Shiny book.
Chat interface
- The
shinychatpackage provides a pretty interface and useful functions to add a chatbot functionality in R Shiny.
library(shiny)
library(ellmer)
library(shinychat)
ui <- bslib::page_fillable(
chat_ui("chat")
)
server <- function(input, output, session) {
chat <- chat_openai("You are a Socrates statistics tutor.
Don't ever tell the answer.",
model = "gpt-4.1-mini")
chat_append("chat", "Hi there! How can I help you with STAT101?")
observeEvent(input$chat_user_input, {
stream <- chat$stream_async(input$chat_user_input)
chat_append("chat", stream)
})
}
shinyApp(ui, server)
Processing images
- Not all models can process images.
- There are three ways to input the image into the chat object:
content_image_url() # an image hosted on web
content_image_file() # an image on the local file system
content_image_plot() # from R plot
chat <- ellmer::chat_openai()
chat$chat("Identify the animal in the image",
content_image_url("https://upload.wikimedia.org/wikipedia/commons/1/15/Cat_August_2010-4.jpg"))The animal in the image is a domestic cat (Felis catus). It
appears to be a tabby cat, characterized by its striped fur
pattern.Processing PDFs
- A sample copy of the 2021 Census Special Short Form can be found here.
- We use the Gemini model here as the Open AI model via
ellmerdoesn’t support this yet.
chatg <- chat_google_gemini()
chatg$chat("Extract the questions from the following pdf.",
content_pdf_url("https://www.abs.gov.au/system/files/documents/481decdb18d925785b9dfc20727c5cff/Sample%20Special%20Short%20Form%20%5B156KB%5D.pdf"))Here are the questions extracted from the provided PDF:
1. Where did you sleep on Census night, Tuesday 10 August
2021?
2. Are you:
3. What is your date of birth and age?
4. Are you of Aboriginal or Torres Strait Islander origin?
5. What is your current marital status?
6. In which country were you born?
7. What is your total weekly income from all sources?
8. Have you ever served in the Australian Defence Force?
9. What is your name?
10. Do you agree to your name and other information on this
form being kept by the National Archives of Australia and
then made publicly available after 99 years?
11. Declaration