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JavaScript’s Filter Function Explained By Applying To College

Kevin Kononenko on June 03, 2018

If you are familiar with the college application process, then you can understand JavaScript’s filter functions. Compared to the map() and reduce(...

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bojanorter • Jun 4 '18 • Edited

For filtering like this,

let admitted = students.filter(function(student){
   return student.gpa > 3.2 && student.sat > 1900;
})

i would use arrow functions new in ECMAScript 6.

then this becomes

let admitted = students.filter(student => 
student.gpa > 3.2 && student.sat > 1900
})

Other than that, I liked your post.

Kevin Kononenko • Jun 4 '18

Yeah, it is always tough for me to decide which version to use, maybe I just need to start including the second version in comments :)

Kamal • Jun 3 '18 • Edited

this is nice! Thanks!

edit

you should fix the typo in the student attributes, because it's case sensitive

Kevin Kononenko • Jun 3 '18

Thanks Kamal! which one are you talking about?

Ishmael Sunday • Jun 3 '18 • Edited

Some of the names start with caps and other don’t. They all should start lower or uppercase for consistency.

Also in your explanation, you said they need 3.2 or up. The function is not considering 3.2. You used (>) which excludes 3.2. Should it be >= ? You might want to as “s” word student in the return. students.gpa etc.

I am just a beginner. Starting my first JS class on the 18th. Thanks for the article too.

Kevin Kononenko • Jun 4 '18

Hey Ishmael, yep, you are correct about the 3.2 thing. As for "students" v. "Students", I tried to use the uppercase when referring to actual students, and lowercase when referring to the students array.

My original article uses interactive images that make this a little more clear:

blog.codeanalogies.com/2018/05/14/...