JavaScript reduce() method in 5 minutes! ♻

// .reduce() = reduce the elements of an array
// to a single value
// ---------- EXAMPLE 1 ----------
const prices = [5, 30, 10, 25, 15, 20];
const total = prices.reduce(sum);
console.log(`$${total.toFixed(2)}`);
function sum(accumulator, element){
return accumulator + element;
}
// ---------- EXAMPLE 2 ----------
const scores = [75, 50, 90, 80, 65, 95];
const maximum = scores.reduce(getMax);
const minimum = scores.reduce(getMin);
console.log(maximum);
console.log(minimum);
function getMax(accumulator, element){
return Math.max(accumulator, element);
}
function getMin(accumulator, element){
return Math.min(accumulator, element);
}

[@BroCodez]

// .reduce() = reduce the elements of an array // to a single value // ----------- EXAMPLE 1 ----------- const prices = [5, 30, 10, 25, 15, 20]; const total = prices.reduce(sum); console.log(`$${total.toFixed(2)}`); function sum(accumulator, element){ return accumulator + element; } // ----------- EXAMPLE 2 ----------- const scores = [75, 50, 90, 80, 65, 95]; const maximum = scores.reduce(getMax); const minimum = scores.reduce(getMin); console.log(maximum); console.log(minimum); function getMax(accumulator, element){ return Math.max(accumulator, element); } function getMin(accumulator, element){ return Math.min(accumulator, element); }

[@user-mk2md9pu5m]

Django course please

[@Praeda19]

Dude, thank you SO much, the way you've explained how the three data transformation array methods work, as well as the how the forEach loop works, is incredibly easy to understand. I've finally got my head around how the forEach loop works, and now JS is (ifnally) starting to click with me. Again, thank you, and all the best!!

[@geldelian]

You said that the first iteration would be sum(0, 5), but that is not true. If you don't set the initial value for reduce the first value will be taken as 1 element of the array and the first iteration will be sum(5, 30).

[@RafaelSilva-rv6kt]

Yeah, if you think about it, the minimum value would be 0 if that was the case, and not 50

[@Mochinori99]

This video is absolutely brilliant and so so clear. I love your videos. Thank you.

[@RayhanAsif22]

Dude I've learned a lot from your videos !!

[@zrotrasukha8733]

Thank you brother, you helped me a lot, May god bless you !!

[@pini5076]

thank you so much!

[@pexhay4690]

is there any difference between defining the callback that way and using arrow notation inside reduce like prices.reduce((accum, el) =>{...})

[@ianfrye8988]

For the most part no, just depends on if you’re going to reuse that function… when you get into the “this” keyword it does depending on the context

[@pexhay4690]

@@ianfrye8988 thank you

[@magomihaly1741]

You re the man thx bro

[@islamabdelhakiim7258]

thank you so much

[@rukecodes]

Thanks bro!!!!!!

[@kathikr9360]

thank you dude

[@manitamao6564]

Thank u bro

[@nomanbangtan4120]

Bro you should do a project video.

[@javohir1704]

would be a way better if you added a initialValue parameter but thank you though

[@kathikr9360]

thanks again

[@greengraphics5060]

Do a node js video

[@cyberblitz]

shame you didn't include the initial value parameter too. Otherwise, very educational.

[@user-mk2md9pu5m]

django course please

[@devl0ver666]

now i know why your channel name is bro code ................. :)

[@ianfrye8988]

Also all other JavaScript higher order array methods can be created with reduce