visNetwork R Package

The canvas-toBlob.js utility provides polyfills for the standard HTML5 canvas.toBlob() and canvas.toBlobHD() methods. This is useful for ensuring network visualizations can export canvas content in browsers that do not natively support these methods.

Requirement: canvas-toBlob.js requires Blob support to function. If you are targeting browsers that lack Blob support, you must also include a cross-browser Blob implementation like Blob.js.

You can install the stable version of visNetwork from CRAN using install.packages(). If you need the development version, use devtools::install_github().

# Install stable version from CRAN
install.packages("visNetwork")

# Install development version
devtools::install_github("datastorm-open/visNetwork")

You can perform feature detection to check if the Blob interface is available, which is a prerequisite for FileSaver.js functionality.

try {
    var isFileSaverSupported = !!new Blob;
} catch (e) {}

The package provides several ways to access documentation and extended examples:

• R Help: Use ?visNetwork in your R console.
• Vignettes: Run vignette("Introduction-to-visNetwork") to see the introductory guide.
• JavaScript Documentation: Call visDocumentation() to view the full documentation for the underlying vis.js library.
• Online Docs: Visit http://datastorm-open.github.io/visNetwork.

To save text, create a new Blob with the desired text content and MIME type (e.g., text/plain;charset=utf-8), then pass it to saveAs().

var blob = new Blob(["Hello, world!"], {type: "text/plain;charset=utf-8"});
saveAs(blob, "hello world.txt");

You can launch a built-in Shiny application provided by the package to explore its capabilities and examples in a web interface.

shiny::runApp(system.file("shiny", package = "visNetwork"))

To save the contents of an HTML5 canvas, use the canvas.toBlob() method. Once the blob is generated, pass it to saveAs().

var canvas = document.getElementById("my-canvas"), ctx = canvas.getContext("2d");
// draw to canvas...
canvas.toBlob(function(blob) {
    saveAs(blob, "pretty image.png");
});

To create a basic network, define a nodes data frame with an id column and an edges data frame with from and to columns. Pass both to the visNetwork() function.

require(visNetwork)

nodes <- data.frame(id = 1:3)
edges <- data.frame(from = c(1,2), to = c(1,3))
visNetwork(nodes, edges)

The primary method provided by FileSaver.js is saveAs().

Signature: FileSaver saveAs(Blob data, DOMString filename, optional Boolean disableAutoBOM)

Parameters:

• data: The Blob object containing the data to be saved.
• filename: The name of the file to be saved.
• disableAutoBOM (optional): A boolean. If set to true, FileSaver.js will not automatically provide Unicode text encoding hints (Byte Order Mark).

Tipue Search uses specific global variables to define the scope of the search index and which words should be ignored during indexing.

• tipuesearch_pages: An array of strings containing the relative paths to the HTML pages that should be included in the search index.
• tipuesearch_stop_words: An array of strings representing words that the search engine should ignore (e.g., common articles and prepositions).

var tipuesearch_pages = [
  "../network/layout.html",
  "../network/configure.html"
];

var tipuesearch_stop_words = ["a", "about", "above"];

You can localize or customize the text displayed in the Tipue Search interface by overriding the tipuesearch_string_N variables (where N is 1 through 13).

Available string keys:

• tipuesearch_string_1: 'No title'
• tipuesearch_string_2: 'Showing results for'
• tipuesearch_string_3: 'Search instead for'
• tipuesearch_string_4: '1 result'
• tipuesearch_string_5: 'results'
• tipuesearch_string_6: 'Prev'
• tipuesearch_string_7: 'Next'
• tipuesearch_string_8: 'Nothing found'
• tipuesearch_string_9: 'Common words are largely ignored'
• tipuesearch_string_10: 'Search too short'
• tipuesearch_string_11: 'Should be one character or more'
• tipuesearch_string_12: 'Should be'
• tipuesearch_string_13: 'characters or more'

var tipuesearch_string_1 = 'Custom Title';
var tipuesearch_string_8 = 'No matches found';