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JavaScript JavaScript Array Iteration Methods Combining Array Methods Combining filter() and reduce()

Posted by Istvan Toth
Istvan Toth
14,348 Points

Why do we need filter to make things more complicated if reduce does the job by itself?

const pricesOver10 = products.reduce((pricesAll,price) => {if(price.price > 10){pricesAll += price.price}return pricesAll},0).toFixed(2)

Trent Stenoien
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.a{fill-rule:evenodd;}techdegree seal-36
Trent Stenoien
Full Stack JavaScript Techdegree Graduate 21,632 Points
Trent Stenoien
.a{fill-rule:evenodd;}techdegree seal-36
Trent Stenoien
Full Stack JavaScript Techdegree Graduate 21,632 Points

Reduce adds up the sum, filter replaces your 'if' statement. My syntax might be not be perfect, but this is the idea.

const pricesOver10 = products.filter(price.price > 10).reduce((pricesAll,price) => pricesAll += price.price, 0).toFixed(2)

1 Answer

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

You might not have used the .filter method, but you've recreated its functionality in your conditional code. While this is a technically legitimate solution, it's less compact than the video example and requires about 50% more space.