React Javascript Multiple Arrays to an Object of Arrays

Question

I have a set of arrays that have multiple bits of data that I want to arrange into a new array of data. This is what I have:

const dateArray = ["9/13/2022", "9/13/2022", "9/13/2022", "9/13/2022","9/13/2022"]
const timeArray = ["00:00", "00:01", "00:02", "00:03", "00:04"]
const integerArray = [1,2,3,4,5]

This is what I want:

{
 row0: ["9/13/2022", "00:00", 1],
 row1: ["9/13/2022", "00:01", 2],
 row2: ["9/13/2022", "00:02", 3],
 row3: ["9/13/2022", "00:03", 4],
 row4: ["9/13/2022", "00:04", 5]
}

Thanks for any info you could provide, I've tried to do map, reduce and group but I haven't had exactly what I want to come back and I'm losing my mind keeping track of what I've tried.

• Harshit Pant: Will all the three arrays have equal number of items. If that is the case you can just create a for loop on length of any array. Then insert an object rowIndex as dateArray[i], timeArray[i] and integerArray[i]

Answer 1

Using Array#reduce:

const dateArray = ["9/13/2022", "9/13/2022", "9/13/2022", "9/13/2022","9/13/2022"]
const timeArray = ["00:00", "00:01", "00:02", "00:03", "00:04"]
const integerArray = [1,2,3,4,5]
const res = dateArray.reduce((acc, _, i, dates) => ({
 ...acc, [`row${i}`]: [dates[i], timeArray[i], integerArray[i]]
}), {});
console.log(res);

• Chris G: cool but can you please explain what happened there? what is _ for example?
• Majed Badawi: @ChrisG as linked in the docs, the second param is the current-value which we're not using in the solution. _ is just a common-practice to tell that this variable is to be ignored. Does this answer your question?
• gilly2chilly: @MajedBadawi, thank you so much for the prompt answer and the breakdown afterwards, I tried so many attempts of reduce and see now why my code flopped, thank you!