replace List with [] in static series, then covert at end return (it’s faster)

[DaveSkender]

See EMA in v3 for example. Keep in mind, this approach is only faster in certain circumstances, so performance test comparison is required to see where it's better. For example, the simple ADL indicator remains faster with List<AdlResult> composition.

To avoid copying the underlying array, remember to use:

return new List<TrResult>(results);

Instead of:

return results.ToList();

References and examples:

• refactor: Performance tuning (stream + incr experiments) #1230 (comment)

Stock.Indicators/src/e-k/Ema/Ema.StaticSeries.cs

Line 17 in 8b02491

EmaResult[] results = new EmaResult[length];