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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] 💬

csharp
// C# usage syntax
IReadOnlyList<DemaResult> results =
  bars.ToDema(lookbackPeriods);

Parameters

paramtypedescription
lookbackPeriodsintNumber 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

csharp
IReadOnlyList<DemaResult>
  • This method returns a time series of all available indicator values for the bars provided.
  • 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-1 periods will have null values 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

propertytypedescription
TimestampDateTimeDate from evaluated TBar
DemadoubleDouble exponential moving average

Utilities

See Utilities and helpers for more information.

Chaining

This indicator may be generated from any chain-enabled indicator or method.

csharp
// example
var results = bars
    .Use(CandlePart.HL2)
    .ToDema(..);

Results can be further processed on Dema with additional chain-enabled indicators.

csharp
// 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:

csharp
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:

csharp
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.