Double Exponential Moving Average (DEMA)
Created by Patrick G. Mulloy, the Double exponential moving average is a faster smoothed EMA of the price over a lookback window. [Discuss] 💬
// C# usage syntax
IReadOnlyList<DemaResult> results =
bars.ToDema(lookbackPeriods);Parameters
| param | type | description |
|---|---|---|
lookbackPeriods | int | Number of periods (N) in the moving average. Must be greater than 0. |
Historical price bars requirements
You must have at least 3×N or 2×N+100 periods of bars, whichever is more, to cover the warmup and convergence periods. Since this uses a smoothing technique, we recommend you use at least 2×N+250 data points prior to the intended usage date for better precision.
bars is a collection of generic TBar historical price bars. It should have a consistent frequency (day, hour, minute, etc). See the Guide for more information.
Response
IReadOnlyList<DemaResult>- This method returns a time series of all available indicator values for the
barsprovided. - It always returns the same number of elements as there are in the historical price bars.
- It does not return a single incremental indicator value.
- The first
N-1periods will havenullvalues since there's not enough data to calculate.
🚩 ⚞ Convergence warning
The first 2×N+100 periods will have decreasing magnitude, convergence-related precision errors that can be as high as ~5% deviation in indicator values for earlier periods.
DemaResult
| property | type | description |
|---|---|---|
Timestamp | DateTime | Date from evaluated TBar |
Dema | double | Double exponential moving average |
Utilities
See Utilities and helpers for more information.
Chaining
This indicator may be generated from any chain-enabled indicator or method.
// example
var results = bars
.Use(CandlePart.HL2)
.ToDema(..);Results can be further processed on Dema with additional chain-enabled indicators.
// example
var results = bars
.ToDema(..)
.ToRsi(..);See Chaining indicators for more.
Streaming
Use the buffer-style List<T> when you need incremental calculations without a hub:
DemaList demaList = new(lookbackPeriods);
foreach (IBar bar in bars) // simulating stream
{
demaList.Add(bar);
}
// based on `ICollection<DemaResult>`
IReadOnlyList<DemaResult> results = demaList;Subscribe to a BarHub for advanced streaming scenarios:
BarHub barHub = new();
DemaHub observer = barHub.ToDemaHub(lookbackPeriods);
foreach (IBar bar in bars) // simulating stream
{
barHub.Add(bar);
}
IReadOnlyList<DemaResult> results = observer.Results;See Buffer lists and Stream hubs for full usage guides.