How Can I Efficiently Sum the Values of a Specific Property Across Multiple JavaScript Arrays?

Efficient Array Value Summation

This question seeks an efficient solution for calculating the total sum of a specific property across multiple arrays.

Problem Statement

Given an array of objects, each containing a "description" and an "Amount" property, the original approach involved iterating through the array and incrementally adding the "Amount" values:

$scope.totalAmount = function(){
       var total = 0;
       for (var i = 0; i < $scope.traveler.length; i++) {
              total = total + $scope.traveler[i].Amount;
            }
       return total;
}

Equivalent Method for Arbitrary Properties

The desired solution would allow for summing of arbitrary property values, expressed as:

$scope.traveler.Sum({ Amount });
$scope.someArray.Sum({ someProperty });

Optimized Solution

The proposed solution leverages the array.reduce method to achieve this goal:

$scope.sum = function(items, prop){
    return items.reduce( function(a, b){
        return a + b[prop];
    }, 0);
};

$scope.travelerTotal = $scope.sum($scope.traveler, 'Amount');

Advantages

• Reusability: This solution can be reused for any array by passing the appropriate arguments to the sum function.
• Conciseness: It encapsulates the summing logic in a single method, eliminating the need for explicit iteration loops.
• Improved Performance: Reduce provides inherent performance optimizations for array processing.

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