find how many array values have an absolute value

Question

i want to find number of failed values in an array

let courcesStatus = ["passed", "failed", "passed", "passed", "passed", "failed"];

for example want to have 2 here as the number of failed values in this array

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score 0 · Answer 1 · answered Jun 18 '21 at 18:52

This is how I would do it, using filter() and length:

let courcesStatus = ["passed", "failed", "passed", "passed", "passed", "failed"];

const howManyFailed = arr => arr.filter(value => value === "failed").length;
console.log(howManyFailed(courcesStatus)); // 2

You could also achieve this with reduce():

let courcesStatus = ["passed", "failed", "passed", "passed", "passed", "failed"];

const howManyFailed = arr => arr.reduce((accu, curr) => accu + (curr === "failed" ? 1 : 0), 0)
console.log(howManyFailed(courcesStatus)); // 2

More information on both of those methods here:

.filter() (MDN Docs)
.reduce() (MDN Docs)

find how many array values have an absolute value

1 Answers1