my-idlers/node_modules/collect.js/docs/api/avg.md

avg()

The avg method returns the average of all items in the collection:

collect([1, 3, 3, 7]).avg();

// 3.5

If the collection contains nested arrays or objects, you should pass a key to use for determining which values to calculate the average:

const collection = collect([
  {
    name: 'My story',
    pages: 176,
  },
  {
    name: 'Fantastic Beasts and Where to Find Them',
    pages: 1096,
  },
]);

collection.avg('pages');

// 636

You may also define a callback function

const collection = collect([
  {
    name: 'My story',
    pages: 176,
  },
  {
    name: 'Fantastic Beasts and Where to Find Them',
    pages: 1096,
  },
]);

collection.avg(book => book.pages);

// 636

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