Scale Filter

The fledge-filter-scale plugin is a simple filter that allows a scale factor and an offset to be applied to numerical data. It’s primary uses are for adjusting values to match different measurement scales, for example converting temperatures from Centigrade to Fahrenheit or when a sensor reports a value in non-base units, e.g. 1/10th of a degree.

When adding a scale filter to either the south service or north task, via the Add Application option of the user interface, a configuration page for the filter will be shown as below;

scale

The configuration options supported by the scale filter are detailed in the table below

Setting

Description

Scale Factor

The scale factor to multiply the numeric values by

Constant Offset

A constant to add to all numeric values after applying the scale

Asset filter

This is useful when applying the filter in the north, it allows the filter to be applied only to those assets that match the regular expression given. If left blank then the filter is applied to all assets/

See Also

fledge-filter-expression - A Fledge processing filter plugin that applies a user define formula to the data as it passes through the filter

fledge-filter-fft - A Fledge processing filter plugin that calculates a Fast Fourier Transform across sensor data

fledge-filter-log - A Fledge filter that converts the readings data to a logarithmic scale. This is the example filter used in the plugin developers guide.

fledge-filter-metadata - A Fledge processing filter plugin that adds metadata to the readings in the data stream

fledge-filter-omfhint - A filter plugin that allows data to be added to assets that will provide extra information to the OMF north plugin.

fledge-filter-python35 - A Fledge processing filter that allows Python 3 code to be run on each sensor value.

fledge-filter-rms - A Fledge processing filter plugin that calculates RMS value for sensor data

fledge-filter-scale-set - A Fledge processing filter plugin that applies a set of sale factors to the data

fledge-south-Expression - A Fledge south plugin that uses a user define expression to generate data