How do we sum each array element in multiple arrays
ex : [[2, 1], [1, 4]]
output : [3], [5]
In this code is the sum based on the index in each array
const in_out = [
[2, 1],
[1, 4]
]
function calculate(arr) {
a = arr.reduce((prev, curr) => prev + curr[idx = 0], 0)
b = arr.reduce((prev, curr) => prev + curr[idx = 1], 0)
c = [a + b]
return c
}
console.log(calculate(in_out))and what I want is summation based on each array, and dynamic "in_out" variable like this
[2, 1] = 3 and [1, 4] = 5
console.log(calculate (in_out [[2, 1], [1, 4]] ) );
and the output
[8]
Use Array.reduce() method 2 times, the outer one will give you the transformed array and the nested one will give you the sum.
const list = [
[2, 1],
[1, 4]
];
function calculate(arr) {
return arr.reduce((acc, items) => acc.concat(items.reduce((sum, curr) => sum + curr, 0)), [])
}
console.log(calculate(list))Just map and reduce:
const in_out = [[2, 1],[1, 4],[1,2,3,4],[],[9,8,7,6],[9]];
const calculate = (data) =>
data.map((arr) =>
arr.reduce((sum, num) => sum + num, 0)
);
console.log(calculate(in_out));.as-console-wrapper{min-height: 100%!important; top: 0}Conventional way!
function sumTwoDimensi(arr){
var arrSum = [];
for(let i = 0; i < arr.length; i++) {
var sum = 0;
for (let j = 0; j < arr[i].length; j++) {
sum = (sum+arr[i][j]);
}
arrSum[i] = sum;
}
return arrSum
}
Then to calculate all of it, just this function:
function sumArr(ar) {
var sum = 0;
for (var i = 0; i < ar.length; i++) {
sum += ar[i];
}
return sum;
}
Example for use it:
console.log(sumTwoDimensi(in_out));
console.log(sumArr(sumTwoDimensi(in_out)));
Just copy it!