I know that for an array it can be used last function of underscore, so in the case of this array it would be:
myArray = [32, 1, 8, 31];
lastElement = _.last(myArray);
The problem is when there is a matrix like this:
myArray = [[1, 3, 5], [55, 66, 77], [0, 1, 2]];
and the wanted result is
lastElement = [5, 77, 2];
Any suggestions?
Use map and slice (Won't mutate the original array)
[[1, 3, 5], [55, 66, 77], [0, 1, 2]].map( s => s.slice(-1)[0] );
You can just do
var lastElement = myArray.map(_.last);
You could simply use Array.from :
var myArray = [[1, 3, 5], [55, 66, 77], [0, 1, 2]];
var res = Array.from(myArray, x => x[x.length - 1]);
console.log(res);Another possibility not already answered here would be Array#reduce :
var myArray = [[1, 3, 5], [55, 66, 77], [0, 1, 2]];
var res = myArray.reduce((acc, curr) => acc.concat(curr[curr.length - 1]),[]);
console.log(res);
var lastElement = myArray.map((x) => {
return _.last(x);
});
Or you can also use ES6 map
let myArray = [[1, 3, 5], [55, 66, 77], [0, 1, 2]];
let result = myArray.map(v => v[ v.length - 1] );
console.log(result );Check this out. Iterate over the array using map and extract last element.
No need of any library.
let myArray = [[1, 3, 5], [55, 66, 77], [0, 1, 2]];
let output = [];
output = myArray.map(m => m[m.length - 1] )
console.log(output)
.map. Please check other answers
.map is used to get some mutated/parsed value of every item. It returns n items but with specific value. .forEach will loop over and process values but will not return anything. So if you use .map but do not return value or do not respect/accept returned value, its essentially same as .forEach. All array functions are meant for a reason. Yes you can achieve same task from all methods but you should use them for intended purpose, else you are killing their essence.You can use array.prototype.map to transorm each subarray to the last element in it. You can get those last elements with array.prototype.pop or arr[arr.length - 1] if you don't want to mutate myArray:
var myArray = [[1, 3, 5], [55, 66, 77], [0, 1, 2]];
var lastElements = myArray.map(arr => arr.pop());
console.log(lastElements);
.pop() will mutate array. Better use .slice().pop() or arr[arr.length - 1]Perhaps loop through them with a for loop.
lastElement = [];
for (var i = 0 ; i < myArray.length ; i++) {
lastElement.push(_.last(myArray[i]));
}
Use Following Code:-
var myArray = [[1, 3, 5], [55, 66, 77], [0, 1, 2]];
lastElement = _.map(myArray, _.last);
console.log(lastElement)
// **Result is lastElement = [5, 77, 2];**<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js"></script>
<> icon in editor). if you do not need the edit, please revert the changes.
_.last(_.zip(...myArray))