Description 
An exponential moving average is a type of moving average, similar to a moving average, except that more weight is given to the latest data. It is also known as the exponentially weighted moving average 

Input 
Time Series – multiple (Single or multiple time series) 

Parameters 
Period [Mandatory] 
Relative_time [default=10 days] 
Output 
Transformed Time Series  multiple 

Available in 
Alerts + Composite + Dashboards 
USAGE EXAMPLE
The expMovingAverage function is useful in cases when you want to smooth a noisy metric.
Let’s take the following raw metric as an example, which counts the number of application errors in a given instance:
It is a sparse metric, as the majority of the input here is just zeros. In addition, the seasonality is not perfect, as the daily peaks emerge with some jitter. In fact, this noise hampers the baseline model selection, and leaves this metric inadequate for anomaly detection (all those daily surges will be falsely classified as anomalies).
After applying the expMovingAverage function (using a 30 minutes moving window), the baseline for this metric becomes much better:
Note:
 The expMovingAverage removes the data from its original, raw values.
 Some downsampling of the data will occur.