JSFiddle - React, Tailwind, and code Playground

JavaScript

$scope = function() {};
$scope.data = {};
$scope.data.artists = ["Aa", "Bb"];
    
$scope.sortedNames = {
    A : [],
    B : []
};

function foo() {
    //loop to go through my artists array
    for (var i = 0; i < $scope.data.artists.length; i++) {
        //loop to go through my sortedNames array
        $scope.sortedNames[$scope.data.artists[i].charAt(0)].push($scope.data.artists[i]);
    }
}
    
foo();
console.log($scope.sortedNames);