How to get from flat data to a Network Graph

This article followsprovide follow up fromto the Network GraphGraphs article.

A typical process for creating networks out of flat datasets, such as aseparate listlists of people,people and projects, is to iterate through a dataset having say people in each row, looking for unique values in a categoricalcolumn column, like acontaining project name,names, turn those project names into new nodes, and then connect those new project name nodes up to the people rows.

 The above dataset started out as a simple list of ids with "tags"

Running it through the algorithm described, results in new nodes added, in this case A, B, and C, each with connection to the ids 1 through 6 based on the tags present.

Javascript proto-code for this looks like this:

	var nodes = [];
	var tag_column_name = "tag";
    
	for (var i = 1; i < rows.length-1; i++) {
      var row = rows[i].split(",");
      var node = {};
      for (var j = 0; j < header.length; j++) {
        node[header[j]] = row[j];
		node['type']='node';
		node['connections']=undefined;
		node['connectionCount']=undefined;
      }
      nodes.push(node);
      if (!tagMap[node[tag_column_name]]) {
        tagMap[node[tag_column_name]] = [];
      }
      tagMap[node[tag_column_name]].push(node.id);
    }
    var taglist = Object.entries(tagMap).map(([key, value]) => ({ id: key, links: value }));

    for (var i = 0; i < taglist.length; i++) {
      taglist[i].type = tag_column_name;
      taglist[i].connections = taglist[i].links ? taglist[i].links.join("|"): null;
      taglist[i].connectionCount = taglist[i].links ? taglist[i].links.length : 0;
      nodes.push(taglist[i]);
    }