Split Array into Arrays of X length

split-array-into-arrays-of-x-length.js

let srcAry = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]
let splitBy = 3
let split = []

srcAry.forEach((val, i) => {
  let ary = i % splitBy ? split[split.length - 1] : (split[split.length] = [])
  ary.push(val)
})

console.log(split)

const dividedArray = (srcAry = [], splitBy = 1) => {
  const split = []

  srcAry.forEach((val, i) => {
    const ary = i % splitBy ? split[split.length - 1] : (split[split.length] = [])
    ary.push(val)
  })

  return split
}