Suppose we have an array of objects like this −
const arr = [ {val: 56, canUse: true}, {val: 16, canUse: true}, {val: 45, canUse: true}, {val: 76, canUse: false}, {val: 45, canUse: true}, {val: 23, canUse: false}, {val: 23, canUse: false}, {val: 87, canUse: true}, ];
We are required to write a JavaScript function that calculates the average of the val property of all those objects that have a boolean true set for the canUse flag.
Example
Following is the code −
const arr = [ {val: 56, canUse: true}, {val: 16, canUse: true}, {val: 45, canUse: true}, {val: 76, canUse: false}, {val: 45, canUse: true}, {val: 23, canUse: false}, {val: 23, canUse: false}, {val: 87, canUse: true}, ]; const excludedAverage = arr => { let count = 0, props = 0; for(let i = 0; i < arr.length; i++){ if(!arr[i].canUse){ continue; }; props++; count += arr[i].val; }; return (count) / (!props ? 1 : props); }; console.log(excludedAverage(arr));
Output
This will produce the following output in console −
49.8