Get all 0 index data in 2d array javascript
let a = [["", "2", "", ""], ["1", "3", "", ""], ["", "", "4", ""]]
index = 0
output = ["", "1", ""]
Similarly get all remaining index data
index= 1
output = ["2", "3", ""]
Add a comment
|
4 Answers
You can use Array#map method with ES6 destructuring feature. Destructuring helps to extract certain property from an object(Javascript Array is also an object).
let a = [
["", "2", "", ""],
["1", "3", "", ""],
["", "", "4", ""]
];
let index = 0;
let output = a.map(({[ index ]: v }) => v)
console.log(output);
index = 1;
output = a.map(({[ index ]: v }) => v)
console.log(output);2 Comments
Sreekanth Reddy
Could you please try this stackoverflow.com/questions/55083788/…
Pranav C Balan
@SreekanthReddy sure let me check
You can use reduce
Loop through arr and for each element in arr loop through to get the desired index value and push it to op.
let a = [["", "2", "", ""], ["1", "3", "", ""], ["", "", "4", ""]]
function getIndex(arr,index){
return arr.reduce((op,inp) => {
let val = inp.find((e,i) => i === index )
op.push(val)
return op
},[])
}
console.log(getIndex(a,0))
console.log(getIndex(a,1))
1 Comment
Sreekanth Reddy
Could you please try this stackoverflow.com/questions/55083788/…
To get the first index:
const result = Array.map(a=>a[0]);
result will contain the first index of all the elements in the nested array. This works by iterating through the array and fetching the first index elements
1 Comment
Sreekanth Reddy
Could you please try this stackoverflow.com/questions/55083788/…
With lodash you can just use the index as an iteratee:
const result = _.map(a, 1);
