I have an array like ;
arr = ["0","22","36","49","54","64","69","82","87","110","115","128","133","143","148","161","166","179","184","197","202","211","216","229","234","246","251","263","268","280","285","297","302","314","319"]
I want to create a new array like
[[0,22],[22,36],[36,49],[49,54]...[314,319], [319]]
I did like
function chunkArray(arr, len) {
const chunkedArr = []
arr.forEach(val => {
const last = chunkedArr[chunkedArr.length - 1];
if (!last || last.length === len) {
chunkedArr.push([val]);
} else {
last.push(val);
}
});
return chunkedArr;
}
const chunked = chunkArray(arr, 2)
But it gives me two part array like;
[["0","22"],["36","49"],["54","64"],["69","82"],["87","110"],["115","128"],["133","143"],["148","161"],["166","179"],["184","197"],["202","211"],["216","229"],["234","246"],["251","263"],["268","280"],["285","297"],["302","314"],["319"]]
This should do it:
const chunked = arr.map((a,i) => [a].concat(i < arr.length - 1 ? [arr[i+1]] : []));
DEMO 1
const arr = ["0","22","36","49","54","64","69","82","87","110","115","128","133","143","148","161","166","179","184","197","202","211","216","229","234","246","251","263","268","280","285","297","302","314","319"]
const chunked = arr.map((a,i) => [a].concat(i < arr.length - 1 ? [arr[i+1]] : []));
console.log( chunked );Or to generalize use:
function chunkArray(arr, len) {
return arr.map((el,i,ar) => ar.slice(i,i+len));
}
const chunked = chunkArray(arr, 3);
console.log( chunked );
DEMO 2
const arr = ["0","22","36","49","54","64","69","82","87","110","115","128","133","143","148","161","166","179","184","197","202","211","216","229","234","246","251","263","268","280","285","297","302","314","319"]
function chunkArray(arr, len) {
return arr.map((el,i,ar) => a.slice(i,i+len));
}
const chunked = chunkArray(arr, 3);
console.log( chunked );I think that what you need is something like this:
function chunkArray(arr, len) {
const chunkedArr = [];
for (val of arr) {
if (chunkedArr.length) {
const last = chunkedArr[chunkedArr.length - 1];
if (last.length < len) {
last.push(val);
}
}
chunkedArr.push([val]);
}
return chunkedArr;
}
arr = ["0","22","36","49","54","64","69","82","87","110","115","128","133","143","148","161","166","179","184","197","202","211","216","229","234","246","251","263","268","280","285","297","302","314","319"];
const chunked = chunkArray(arr, 2);
console.log(chunked);Just read the next value and make a new array. When you get to the end, just append that single index
const arr = ["0", "22", "36", "49", "54", "64", "69", "82", "87", "110", "115", "128", "133", "143", "148", "161", "166", "179", "184", "197", "202", "211", "216", "229", "234", "246", "251", "263", "268", "280", "285", "297", "302", "314", "319"]
const result = arr.map((x, i, a) => i < a.length - 1 ? [+a[i + 1], +x] : [+x]).filter(Boolean);
console.log(result);