I was wondering how you get the sum of multiple arrays within an array of objects. My code is as follows:
const employeeList = [
{
"name": "Ahmed",
"scores": [
"5",
"1",
"4",
"4",
"5",
"1",
"2",
"5",
"4",
"1"
]
},
{
"name": "Jacob Deming",
"scores": [
"4",
"2",
"5",
"1",
"3",
"2",
"2",
"1",
"3",
"2"
]
}];
var sum = 0;
for(let i = 0; i < employeeList.length; i++){
var eachScore = employeeList[i].scores;
const b = eachScore.map(Number);
console.log(b);
sum += parseInt(b);//this is the code that doesn't work
}
console.log(sum);
So the problem is, I can get the two arrays to console log but I'm not sure how to go about summing up each array.. When I do sum += parseInt(b), it just logs how many items are in the array(9). and When I do without parseInt, it concats the numbers together but doesn't sum them up.. I would like to use a .split() method to split the arrays and sum them up individually but I haven't quite figured out how to do it yet.
Because b is an array of numbers, you can't meaningfully use + with it unless you want a comma-joined string. The most functional way to sum up an array is to use reduce, which can be used to iterate over its items and add them all to the accumulator:
b.reduce((a, b) => a + b);
If you want to know the partial sums, I'd use .map to transform each object in the employeeList array into the sum of their scores, by extracting the scores property and using reduce to sum them all up:
const employeeList=[{"name":"Ahmed","scores":["5","1","4","4","5","1","2","5","4","1"]},{"name":"Jacob Deming","scores":["4","2","5","1","3","2","2","1","3","2"]}]
const sum = (a, b) => Number(a) + Number(b);
const output = employeeList.map(({ scores }) => scores.reduce(sum));
console.log(output);
// If you want to sum up the results into a single number as well:
console.log(output.reduce(sum));この記事はインターネットから収集されたものであり、転載の際にはソースを示してください。
侵害の場合は、連絡してください[email protected]
コメントを追加