JSFiddle - React, Tailwind, and code Playground

JavaScript

var matrix = [];
var testnodes = [{id: "aaa", a:10},
                 {id: "aab", a:20},
                 {id: "aac", a:30},
                 {id: "aba", a:40}]

testnodes.forEach(function(node, i) {
    matrix[node.id] = [];
   // [{x: 1, y:2, z:0}, {x:2,y:3,z:0}];
    testnodes.forEach(
        function(node1, j) {
            matrix[node.id][node1.id] = {
                x: j,
                y: i,
                z: 0
            };
        //console.log(i,j, node.id, node1.id, matrix[node.id][node1.id]);
    });
    //console.log(i, matrix[node.id]);
});

for (var i1 in matrix) {
	for (var i2 in matrix[i1])
  console.log("matrix[" + i1 + "][" + i2 + "]",matrix[i1][i2]);
}