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JavaScript Array Iteration Methods

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Return a Single Value from an Array with reduce()

8:50 with Joel Kraft

Use the reduce method to return a single value from an array of values.

Snippets from the Video

const prices = [6.75, 3.10, 4.00, 8.12]; // Total: 21.97

let total = 0;

prices.forEach(price => {
  total += price;
});

console.log(total);

const names = ['Gary', 'Pasan', 'Gabe', 'Treasure', 'Gengis', 'Gladys', 'Tony'];

    // Result: 4

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    Sometimes you need to analyze all of the elements in an array and 0:00
    return just a single value, like a number, string, or object. 0:00
    For example, you might have an array of prices and 0:04
    you wanna get a single value, the total of all the prices. 0:07
    With the reduce method, 0:10
    you can use the elements of an array to compute and return any value you want. 0:12
    The reduce method lets you turn all the items in an array into one value. 0:17
    If you had an array of names, for example, and you wanted to find out how many names 0:22
    there were with a length greater than six, you could use reduce to return that total. 0:27

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