how to use the zipwith function from the rxjs library in javascript

The zipWith function from the RxJS library in JavaScript combines multiple Observables into one by applying a function to each of the elements emitted by the Observables, pairwise according to their index.

Here's an example of how to use zipWith function:

index.tsx
const { from } = rxjs;
const { zipWith } = rxjs.operators;

const source1 = from(['a', 'b', 'c']);
const source2 = from([1, 2, 3]);
const result = source1.pipe(zipWith(source2, (a, b) => `${a}${b}`));

result.subscribe(console.log);
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In the code above, source1 will emit values a, b, and c, and source2 will emit values 1, 2, and 3. The zipWith operator will combine these two Observables and apply the function (a, b) => ${a}${b}`` to each of their pairwise elements. The resulting Observable result will emit the values a1, b2, and c3. Finally, subscribing to this Observable will log these values to the console.