Check out a free preview of the full Reactive Angular 2 with ngrx course:
The "Computed Observables" Lesson is part of the full, Reactive Angular 2 with ngrx course featured in this preview video. Here's what you'd learn in this lesson:
Complex observables can be composed from multiple observable streams using the Observable.combineLatest() method. This type of “computed observable” will receive updates anytime one of the streams is changed. Lukas looks at two different code examples that include computed observables.