node-red-nodes/function/smooth/README.md

node-red-node-smooth
====================

A <a href="http://nodered.org" target="_new">Node-RED</a> node that provides
several simple smoothing algorithms for incoming data values. These include

 - Minimum
 - Maximum
 - Mean
 - Standard Deviation
 - High Pass Smoothing
 - Low Pass Smoothing

Install
-------

Run the following command in your Node-RED user directory - typically `~/.node-red`

    npm install node-red-node-smooth


Usage
-----

A simple node to provide various functions across several previous values,
including max, min, mean, standard deviation, high and low pass filters.

Max, Min, Mean and Standard Deviation work over a rolling window, based on a
specified number of previous values.

The High and Low pass filters use a smoothing factor. The higher the number
the more the smoothing. E.g. a value of 10 is similar to an &alpha; of 0.1.
It is analogous to an RC time constant - but there is no time component to
this as the code is based on events arriving.

If `msg.reset` is received (with any value), all the counters and intermediate values are reset to an initial state.

**Note:** This node only operates on **numbers**. Anything else will try to be
made into a number and rejected if that fails.