Interactive igraph networks in R, Quarto and Shiny

Start with an igraph object:

library(garphieldr)
library(igraph)

network <- make_ring(12)
project <- garphield_project(network)
garphield(project)

garphield_project() creates a .gph project. garphield() displays its graph and saved view in an htmlwidget.

An igraph object displayed in the RStudio Viewer.

Save the project

write_gph(project, "network.gph")

restored <- read_gph("network.gph")
garphield(restored)

The file carries the graph and its visual workspace. The browser workbench and Python package open the same document.

Start from tables

nodes <- data.frame(
  id = c("Ada", "Grace", "Edsger", "Barbara"),
  group = c("language", "language", "algorithms", "systems")
)

edges <- data.frame(
  source = c("Ada", "Grace", "Edsger", "Barbara"),
  target = c("Grace", "Edsger", "Barbara", "Ada"),
  relation = c("influenced", "influenced", "worked with", "influenced")
)

project <- garphield_project(nodes = nodes, edges = edges)
garphield(project)

source, target, and id define the topology. Other columns remain available as node and edge attributes.

Put it in Quarto

Use the same call inside a code chunk:

```{r}
library(garphieldr)
library(igraph)

project <- garphield_project(make_ring(12))
garphield(project)
```

The project rendered inside an HTML document.

Update it from Shiny

Render once, then use a proxy for later changes:

server <- function(input, output, session) {
  project <- garphield_project(make_ring(12))
  output$network <- renderGarphield(project)
  output$clicked <- renderPrint(input$network_node_click)

  observeEvent(input$theme, {
    garphieldProxyRun(
      garphieldProxy("network", session),
      "setTheme",
      list(colorScheme = input$theme)
    )
  })
}

A proxy changes the mounted graph without rebuilding the page.

Continue with the R overview, RStudio and Quarto, or Shiny guide.