打破一组子阵列中的一组用户

Question

I would like to break a array with users:

[
    {name: "Carlos"},
    {name: "Marcos"},
    {name: "Fernando"},
    {name: "Jhon"},
    {name: "Loius"},
    {name: "Jacob"},
]

And get something like this:

[
    [
        {name: "Jhon"},
        {name: "Loius"},
        {name: "Jacob"},
    ],
    [
        {name: "Carlos"},
        {name: "Marcos"},
        {name: "Fernando"},
    ]
]

The criterion for splitting them is that I want that each sub array to have a maximum of 3 users, but the number of sub arrays can be unlimited.

Answer 1

 function splitIntoParts(input, maxElementsPerPart) { const inputClone = [...input]; // create a copy because splice modifies the original array reference. const result = []; const parts = Math.ceil(input.length/maxElementsPerPart); for(let i = 0; i < parts; i++) { result.push(inputClone.splice(0, maxElementsPerPart)); } return result; } console.log(splitIntoParts([ {name: "Carlos"}, {name: "Marcos"}, {name: "Fernando"}, {name: "Jhon"}, {name: "Loius"}, {name: "Jacob"}, {name: "Simon"}, ], 3));

Answer 2

chunk is elegantly expressed using functional style

 const chunk = (xs = [], n = 1) => xs.length <= n ? [ xs ] : [ xs.slice (0, n) ] .concat (chunk (xs.slice (n), n)) const data = [ 1, 2, 3, 4, 5, 6 ] console.log (chunk (data, 1)) // [ [ 1 ], [ 2 ], [ 3 ], [ 4 ], [ 5 ], [ 6 ] ] console.log (chunk (data, 2)) // [ [ 1, 2 ], [ 3, 4 ], [ 5, 6 ] ] console.log (chunk (data, 3)) // [ [ 1, 2, 3 ], [ 4, 5, 6 ] ] console.log (chunk (data, 4)) // [ [ 1, 2, 3, 4 ], [ 5, 6 ] ] console.log (chunk ()) // [ [ ] ]

I think take and drop abstractions make the function read a littler nicer. Your opinion may vary.

const take = (xs = [], n = 1) =>
  xs.slice (0, n)

const drop = (xs = [], n = 1) =>
  xs.slice (n)

const chunk = (xs = [], n = 1) =>
  xs.length <= n
    ? [ xs ]
    : [ take (xs, n) ] .concat (chunk (drop (xs, n), n))

Answer 3

 let data = [ {name: "Carlos"}, {name: "Marcos"}, {name: "Fernando"}, {name: "Jhon"}, {name: "Loius"}, {name: "Jacob"}, ] function toGroupsOf(n, array){ return Array.from( {length: Math.ceil(array.length/n)}, //how many groups (_,i) => array.slice(i*n, (i+1)*n) //get the items for this group ) } console.log(toGroupsOf(3, data));

 .as-console-wrapper{top:0;max-height:100%!important}

or

function toGroupsOf(n, array){
  var groups = Array(Math.ceil(array.length/n));
  for(var i=0; i<groups.length; ++i)
    groups[i] = array.slice(i*n, (i+1)*n);
  return groups;
}