flow like the river

VISUALIZACION/node_modules/ngraph.graph/README.md

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+ngraph.graph
+============
+
+[Graph](http://en.wikipedia.org/wiki/Graph_\(mathematics\)) data structure for
+javascript. This library belongs to a family of javascript graph packages called [ngraph](https://github.com/anvaka/ngraph).
+
+[![build status](https://github.com/anvaka/ngraph.graph/actions/workflows/tests.yaml/badge.svg)](https://github.com/anvaka/ngraph.graph/actions/workflows/tests.yaml)
+
+Install
+=======
+
+With [npm](http://npmjs.org) do:
+
+```
+npm install ngraph.graph
+```
+
+Or download from CDN:
+
+``` html
+<script src='https://unpkg.com/ngraph.graph@20.0.1/dist/ngraph.graph.min.js'></script>
+```
+
+If you download from CDN the library will be available under `createGraph` global name.
+
+## Creating a graph
+Create a graph with no edges and no nodes:
+
+``` js
+var createGraph = require('ngraph.graph');
+var g = createGraph();
+```
+
+## Growing a graph
+The graph `g` can be grown in two ways. You can add one node at a time:
+
+``` js
+g.addNode('hello');
+g.addNode('world');
+```
+
+Now graph `g` contains two nodes: `hello` and `world`. You can also use `addLink()`
+method to grow a graph. Calling this method with nodes which are not present in
+the graph creates them:
+
+``` js
+g.addLink('space', 'bar'); // now graph 'g' has two new nodes: 'space' and 'bar'
+```
+
+If nodes already present in the graph 'addLink()' makes them connected:
+
+``` js
+// Only a link between 'hello' and 'world' is created. No new nodes.
+g.addLink('hello', 'world');
+```
+
+### What to use as nodes and edges?
+The most common and convenient choices are numbers and strings. You can
+associate arbitrary data with node via optional second argument of `addNode()`
+method:
+
+``` js
+// Node 'world' is associated with a string object 'custom data'
+g.addNode('world', 'custom data');
+
+// You can associate arbitrary objects with node:
+g.addNode('server', {
+  status: 'on',
+  ip: '127.0.0.1'
+});
+
+// to get data back use `data` property of node:
+var server = g.getNode('server');
+console.log(server.data); // prints associated object
+```
+
+You can also associate arbitrary object with a link using third optional
+argument of `addLink()` method:
+
+``` js
+// A link between nodes '1' and '2' is now associated with object 'x'
+g.addLink(1, 2, x);
+```
+
+### Enumerating nodes and links
+After you created a graph one of the most common things to do is to enumerate
+its nodes/links to perform an operation.
+
+``` js
+g.forEachNode(function(node){
+    console.log(node.id, node.data);
+});
+```
+
+The function takes callback which accepts current node. Node object may contain
+internal information. `node.id` and `node.data` represent parameters passed to
+the `g.addNode(id, data)` method and they are guaranteed to be present in future
+versions of the library.
+
+To enumerate all links in the graph use `forEachLink()` method:
+
+``` js
+g.forEachLink(function(link) {
+    console.dir(link);
+});
+```
+
+To enumerate all links for a specific node use `forEachLinkedNode()` method:
+``` js
+g.forEachLinkedNode('hello', function(linkedNode, link){
+    console.log("Connected node: ", linkedNode.id, linkedNode.data);
+    console.dir(link); // link object itself
+});
+```
+
+This method always enumerates both inbound and outbound links. If you want to
+get only outbound links, pass third optional argument:
+``` js
+g.forEachLinkedNode('hello',
+    function(linkedNode, link) { /* ... */ },
+    true // enumerate only outbound links
+  );
+```
+
+To get a particular node object use `getNode()` method. E.g.:
+
+``` js
+var world = g.getNode('world'); // returns 'world' node
+console.log(world.id, world.data);
+```
+
+To get a particular link object use `getLink()` method:
+
+``` js
+var helloWorldLink = g.getLink('hello', 'world'); // returns a link from 'hello' to 'world'
+console.log(helloWorldLink);
+```
+
+To remove a node or a link from a graph use `removeNode()` or `removeLink()`
+correspondingly:
+
+``` js
+g.removeNode('space');
+// Removing link is a bit harder, since method requires actual link object:
+g.forEachLinkedNode('hello', function(linkedNode, link){
+  g.removeLink(link);
+});
+```
+
+You can also remove all nodes and links by calling
+
+``` js
+g.clear();
+```
+
+## Listening to Events
+Whenever someone changes your graph you can listen to notifications:
+
+``` js
+g.on('changed', function(changes) {
+  console.dir(changes); // prints array of change records
+});
+
+g.add(42); // this will trigger 'changed event'
+```
+
+Each change record holds information:
+
+```
+ChangeRecord = {
+  changeType: add|remove|update - describes type of this change
+  node: - only present when this record reflects a node change, represents actual node
+  link: - only present when this record reflects a link change, represents actual link
+}
+```
+
+Sometimes it is desirable to react only on bulk changes. ngraph.graph supports
+this via `beginUpdate()`/`endUpdate()` methods:
+
+``` js
+g.beginUpdate();
+for(var i = 0; i < 100; ++i) {
+  g.addLink(i, i + 1); // no events are triggered here
+}
+g.endUpdate(); // this triggers all listeners of 'changed' event
+```
+
+If you want to stop listen to events use `off()` method:
+``` js
+g.off('changed', yourHandler); // no longer interested in changes from graph
+```
+
+For more information about events, please follow to [ngraph.events](https://github.com/anvaka/ngraph.events)
+
+
+License
+=======
+BSD 3-clause