Example 1: sum javascript
console.log(
[1, 2, 3, 4].reduce((a, b) => a + b, 0)
)
console.log(
[].reduce((a, b) => a + b, 0)
)
Example 2: reduce javascript
const sum = array.reduce((accumulator, element) => {
return accumulator + element;
}, 0);
// An example that will loop through an array adding
// each element to an accumulator and returning it
// The 0 at the end initializes accumulator to start at 0
// If array is [2, 4, 6], the returned value in sum
// will be 12 (0 + 2 + 4 + 6)
const product = array.reduce((accumulator, element) => {
return accumulator * element;
}, 1);
// Multiply all elements in array and return the total
// Initialize accumulator to start at 1
// If array is [2, 4, 6], the returned value in product
// will be 48 (1 * 2 * 4 * 6)
Example 3: javascript reduce
var array = [36, 25, 6, 15];
array.reduce(function(accumulator, currentValue) {
return accumulator + currentValue;
}, 0); // 36 + 25 + 6 + 15 = 82
Example 4: reduce javascript
let sum = arr.reduce((curr, index) => curr + index);
Example 5: javascript reduce function
var numbers = [175, 50, 25];
document.getElementById("demo").innerHTML
= numbers.reduce(myFunc);
function myFunc(total, num) {
return total - num;
}
Example 6: reduce javascript
/* this is our initial value i.e. the starting point*/
const initialValue = 0;
/* numbers array */
const numbers = [5, 10, 15];
/* reducer method that takes in the accumulator and next item */
const reducer = (accumulator, item) => {
return accumulator + item;
};
/* we give the reduce method our reducer function
and our initial value */
const total = numbers.reduce(reducer, initialValue)