setup() {
    var nodes = {
      node1: { name: "Node 1" },
      node2: { name: "Node 2" },
      node3: { name: "Node 3" },
      node4: { name: "Node 4" },
    }
    var edges = {
      edge1: { source: "node1", target: "node2" },
      edge2: { source: "node2", target: "node3" },
      edge3: { source: "node3", target: "node4" },
    }
    return { nodes, edges }
  }

So instead of writing node1,node2, and so on, is there a way I can loop and create the exact same thing? Any suggestions are appreciated.

CodePudding user response：

Yes. You can dynamically create property names using something like Object.fromEntries.

Object.fromEntries creates an object from a series of entries, where an "entry" is an array with two elements: a property name, and a value for that property.

Here's an example that recreates your data above:

function setup() {
    const nodes = Object.fromEntries(
      [1,2,3,4].map(n => ["node" n, { name: "Node "   n }])
    )
    const edges = Object.fromEntries(
      [1,2,3].map(n => [
        "edge" n, 
        { source: "node"   n, target: "node"   String(n 1) }
      ])
    )
    return { nodes, edges }
 }
 console.log(setup())

CodePudding user response：

Here's a solution:

const setup = (nodeCount) => {
  const nodes = {};
  const edges = {};

  for (let i = 1; i <= nodeCount; i  ) {
    nodes[`node${i}`] = {
      name: `Node ${i}`
    }
    
    if (i <= nodeCount - 1) {
      edges[`edge${i}`] = {
        source: `node${i}`,
        target: `node${i   1}`
      }
    }
  }

  return { nodes, edges };
}

console.log(setup(4));

CodePudding user response：

Sure you can! Many ways, one of the common ones is:

const nodes = Object.fromEntries(
  Array.from(Array(10).keys())
    .map(i => [`node${i   1}`, {name: `Node ${i   1}`}])
);

/* nodes are:
{
    "node1": {
        "name": "Node 1"
    },
    "node2": {
        "name": "Node 2"
    },
    "node3": {
        "name": "Node 3"
    },
    "node4": {
        "name": "Node 4"
    },
    "node5": {
        "name": "Node 5"
    },
    "node6": {
        "name": "Node 6"
    },
    "node7": {
        "name": "Node 7"
    },
    "node8": {
        "name": "Node 8"
    },
    "node9": {
        "name": "Node 9"
    },
    "node10": {
        "name": "Node 10"
    }
}
*/

CodePudding user response：

The following code has the same result but uses for-loops, please be more specific in your question if you need something else.

setup() {
    var nNodes = 4
    var nEdges = 3
    var nodes = {}
    var edges = {}

    for(i = 1 ; i < nNodes   1; i  ){
        nodes['node' i.toString()] = {"name": "Node "   i.toString()}
    }
    for(i = 1 ; i <nEdges   1; i  ){
        edges['edge' (i 1).toString()] = {"source": "node" i.toString(), "target": "node" (i 1).toString()}
    }
    return { nodes, edges }
  }

CodePudding user response：

You can retrieve the object keys using Object.keys. In your case:

var nodes = {
  node1: { name: "Node 1" },
  node2: { name: "Node 2" },
  node3: { name: "Node 3" },
  node4: { name: "Node 4" }
};

// Retrieve ["node1", "node2", ...] from nodes
var nodeNames = Object.keys(nodes);
var pairs: string[][]= [];

// Create a pair of ["node#n", "node#n 1"]
nodeNames.forEach((nodeName, index) => {
  if (index == nodeNames.length - 1) return;

  pairs.push([nodeName, nodeNames[index   1]);
});

// Make edges from node pairs
var edges = pairs.map((pair) => {
  return {source: pair[0], target: pair[1]};
});