How to insert multiple elements into the same index in a multidimensional array?

Question

I have two arrays that I am trying to combine in GAS, arr2 is multidimensional.

arr1 = ["Diesel", "Solar", "Biomass"]

arr2 = [
        ["ABC", "Nigeria", "Diesel,Solar", 35],
        ["DEF", "Egypt", "Solar,Diesel", 50],
        ["GHI", "Ghana", "Biomass,Diesel", 70]
       ]

What I want to do is push the elements of arr1 into arr2 at index 3 in each row, so it looks like:

newArr = [
          ["ABC", "Nigeria", "Diesel,Solar", "Diesel", 35],
          ["DEF", "Egypt", "Solar,Diesel", "Solar", 50],
          ["GHI", "Ghana", "Biomass,Diesel", "Biomass", 70]
         ]

I have tried to use .map over arr2 to .Splice each row but couldn't get it to work. Any help would be much appreciated!

Possible duplicate of How to insert an item into an array at a specific index (JavaScript)? — messerbill
– messerbill, Commented Apr 9, 2019 at 12:06
So I did try the .Splice method in the thread above. However, I was having trouble understanding how to do it in a multidimensional array. — Ajay Ubhi
– Ajay Ubhi, Commented Apr 9, 2019 at 12:15

User863 · Accepted Answer · 2019-04-09 12:39:27Z

4

Using array.splice() and array.map()

Syntax

array.splice(start[, deleteCount[, item1[, item2[, ...]]]])

let arr1 = ["Diesel", "Solar", "Biomass"]

let arr2 = [
  ["ABC", "Nigeria", "Diesel,Solar", 35],
  ["DEF", "Egypt", "Solar,Diesel", 50],
  ["GHI", "Ghana", "Biomass,Diesel", 70]
]

let newArr = arr2.map((v, i) => v.splice(3, 0, arr1[i]) && v)

console.log(newArr)

edited Apr 9, 2019 at 12:39

answered Apr 9, 2019 at 12:08

User863

20.1k3 gold badges20 silver badges45 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Pranav C Balan · Accepted Answer · 2019-04-09 14:21:43Z

You can use Array#map and Array#splice methods.

let arr1 = ["Diesel", "Solar", "Biomass"],
  arr2 = [
    ["ABC", "Nigeria", "Diesel,Solar", 35],
    ["DEF", "Egypt", "Solar,Diesel", 50],
    ["GHI", "Ghana", "Biomass,Diesel", 70]
  ];

// iterate over the array
let res = arr2.map((arr, i) => {
// copy array values to a new array
  let newA = [...arr];
  // insert new element into array based on index
  newA.splice(3, 0, arr1[i]);
  // return new array
  return newA;
})

console.log(res)

If you want to mutate original array then you can skip the array copying portion and just Array#splice method is enough.

let arr1 = ["Diesel", "Solar", "Biomass"],
  arr2 = [
    ["ABC", "Nigeria", "Diesel,Solar", 35],
    ["DEF", "Egypt", "Solar,Diesel", 50],
    ["GHI", "Ghana", "Biomass,Diesel", 70]
  ];

// iterate over the array and put the value at specific index
arr2.forEach((arr, i) => arr.splice(3, 0, arr1[i]))

console.log(arr2)

Rahul Malu · Accepted Answer · 2019-04-09 12:17:14Z

0

Try using the following code

arr1 = ["Diesel", "Solar", "Biomass"]

arr2 = [
        ["ABC", "Nigeria", "Diesel,Solar", 35],
        ["DEF", "Egypt", "Solar,Diesel", 50],
        ["GHI", "Ghana", "Biomass,Diesel", 70]
       ]
arr2.forEach((subArr, index) => {console.log(subArr.splice(3, 0, arr1[index]));});
console.log(arr2);

answered Apr 9, 2019 at 12:17

Rahul Malu

5662 silver badges9 bronze badges

Comments

adiga · Accepted Answer · 2019-04-09 12:20:00Z

0

With a forEach. Use map if you don't want to mutate the array.

const arr1 = ['Diesel', 'Solar', 'Biomass'];

const arr2 = [
  ['ABC', 'Nigeria', 'Diesel,Solar', 35],
  ['DEF', 'Egypt', 'Solar,Diesel', 50],
  ['GHI', 'Ghana', 'Biomass,Diesel', 70]
];

arr2.forEach((el, i) => {
  el.splice(3, 0, arr1[i]);
});

console.log(arr2);

edited Apr 9, 2019 at 12:20

adiga

35.4k9 gold badges65 silver badges88 bronze badges

answered Apr 9, 2019 at 12:08

Andy

63.6k13 gold badges72 silver badges99 bronze badges

Collectives™ on Stack Overflow

How to insert multiple elements into the same index in a multidimensional array?

4 Answers 4

Comments

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related