Remove array from array of arrays javascript

Question

I want delete array from array of arrays without iterate on them.

the first array is like this :

array1 = [ 
[
[{"id":"A1","y":12},{"id":"A4","y":12}],
[{"id":"A2","y":1}], 
[{"id":"A3","y":6}]  
]

the second array is :

array2 = [{"id":"A1","y":12},{"id":"A4","y":12}]

I use javascript and i want delete array2 from array1.

So sorry for wrong description by the way i found that in my exemple the second array array is

array2 = [{ "id": "A1", "y": 12 }, { "id": "A4", "y": 2 }]

So the two arrays have just one columns which is equal. How i can delete array1 from array2 even they have just one attribute which is equal ?

Thank you.

Array.filter. Array.includes

apple apple
– apple apple

2018-04-18 09:26:21 +00:00
Commented Apr 18, 2018 at 9:26 — apple apple
– apple apple, Commented Apr 18, 2018 at 9:26
array1 is wrong, there is an extra [

brk
– brk

2018-04-18 09:29:21 +00:00
Commented Apr 18, 2018 at 9:29 — brk
– brk, Commented Apr 18, 2018 at 9:29
Are the id's unique?

Arman Charan
– Arman Charan

2018-04-18 09:39:21 +00:00
Commented Apr 18, 2018 at 9:39 — Arman Charan
– Arman Charan, Commented Apr 18, 2018 at 9:39
id is not unique

Lembared Nabil
– Lembared Nabil

2018-04-18 10:16:39 +00:00
Commented Apr 18, 2018 at 10:16 — Lembared Nabil
– Lembared Nabil, Commented Apr 18, 2018 at 10:16

Sikandar Sahab · Accepted Answer · 2018-04-18 09:49:53Z

2

splice is usually used to remove a particular item from the array. I think you want to do something like this:

    var array = [

        [{"name": "sik", "gender": "male"}],
        [{"name": "sug", "gender": "female"}],
        [{"name": "hyd", "gender": "male"}]

    ];

    // it removes the second array from the array: removes the female one.
    array.splice( 1, 1 );

Description: The function splice takes two arguments, first one is for the index of item, and second one until how much you want to delete.

For Example: splice( 2, 5 ) - means that: from the index 2, keep deleting until 5 items.

Hope this helps, Thanks.

answered Apr 18, 2018 at 9:49

Sikandar Sahab

7085 gold badges12 silver badges29 bronze badges

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

Comments

Aleksey Solovey · Accepted Answer · 2018-04-18 10:01:33Z

0

Feels weird, but you can check every element of the array and match to the second array. Either way you need to iterate through your array. You can't simply type array1[i] == array2, you need to check it differently. A hack is to stringify them as JSON and compare strings, but there are other methods you can use to compare arrays.

Here is a simple demo with a for loop

array1 = [
  [{ "id": "A1", "y": 12 }, { "id": "A4", "y": 12 }],
  [{ "id": "A2", "y": 1 }],
  [{ "id": "A3", "y": 6 }]
]
array2 = [{ "id": "A1", "y": 12 }, { "id": "A4", "y": 12 }]
l = array1.length
for (var i = 0; i < l; i++) {
  // if arrays match
  if (JSON.stringify(array1[i]) == JSON.stringify(array2)) {
    // delete the element at `i` position
    array1.splice(i, 1);
    i--;
    l--;
    // break; // if you can guarantee that no more instances will occur 
  }
}
console.log(array1)

edited Apr 18, 2018 at 10:01

answered Apr 18, 2018 at 9:47

Aleksey Solovey

4,1663 gold badges18 silver badges34 bronze badges

1 Comment

Lembared Nabil Over a year ago

i found that in my exemple the second array array is array2 = [{ "id": "A1", "y": 12 }, { "id": "A4", "y": 2 }] So the two arrays have just one columns which is equal. How i can delete array1 from array2 even they have just one attribute which is equal ?

CharanbabuKarnam · Accepted Answer · 2018-04-18 09:53:10Z

In Plain Javascript, we cannot filter them. This will work if u are dealing with valued datatypes. Here you are comparing arrays which are a referenced datatype. so here we need to write our own search stack

function searchForArray(haystack, needle){
var i, j, current;
for(i = 0; i < haystack.length; ++i){
if(needle.length === haystack[i].length){
  current = haystack[i];
  for(j = 0; j < needle.length && needle[j] === current[j]; ++j);
  if(j === needle.length)
    return i;
}
}
return -1;
}

var arr = [[1,3],[1,2]];
var n   = [1,3];

console.log(searchForArray(arr,n));

You can refer this question which has some reference resources too. Check whether an array exists in an array of arrays?

I know you asked for a solution without iteration, but i just thought to give an idea of references which may be useful for u.

Collectives™ on Stack Overflow

Remove array from array of arrays javascript

3 Answers 3

Comments

1 Comment

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related