GY-63_MS5611/libraries/RunAvgWeight

RunAvgWeight

Arduino library to calculate the running average with weights by means of a circular buffer.

Description

Experimental

The RunAvgWeight object gives a running average of the last N floating point numbers, while giving them a different weight.

This is done by adding the new data to the internal circular buffers, removing the oldest and replace them by the newest. The size of the internal buffers must be set in the constructor.

The interface of the RunAvgWeight object is strongly based upon RunningAverage. However not all functions are implemented. Note the RunningAverage library uses no weights.

Warning

However the constant adding and subtracting when adding new elements to the RAW object possibly introduces an ever increasing error. In tests with RunningAverage library (with equal weights), adding up to 1500000 numbers this error was always small. Still you need to be aware of this limit.

Related

• https://github.com/RobTillaart/Correlation
• https://github.com/RobTillaart/GST - Golden standard test metrics
• https://github.com/RobTillaart/Histogram
• https://github.com/RobTillaart/RunningAngle
• https://github.com/RobTillaart/RunAvgWeight
• https://github.com/RobTillaart/RunningAverage
• https://github.com/RobTillaart/RunningMedian
• https://github.com/RobTillaart/statHelpers - combinations & permutations
• https://github.com/RobTillaart/printHelpers - print scientific format
• https://github.com/RobTillaart/Statistic

Interface

#include "RunAvgWeight.h"

Constructor

• RunAvgWeight(uint16_t size) allocates dynamic memory, two floats (8 bytes) per element. The object has no default size.
• ~RunAvgWeight() destructor to free the memory allocated.

Basic

• void clear() empties the internal buffers.
• void addValue(float value, float weight = 1.0) adds a new value to the object, if the internal buffer is full, the oldest element is removed. The default weight is 1.0 so one can use this class as a "unweighted" running average too, albeit with the extra overhead.
  addValue() updates the sum of values and weights for the getFastAverage() function.
• float getValue(uint16_t position) returns the value at position from the additions. Position 0 is the first one to disappear.
• float getWeight(uint16_t position) returns the weight at position from the additions. Position 0 is the first one to disappear.
• float getAverage() iterates over all elements, values and weights, to get the average. This is the slower and the more accurate method. A call to getAverage() updates the internal variables used by getFastAverage() to improve its accuracy again.
• float getFastAverage() reuses previous calculated values, therefore faster. Accuracy can drift.

Extended functions

• float getStandardDeviation() returns the standard deviation of the current content. More than one element needs to be added to be calculable.
• float getStandardError() returns the standard error of the current content.
• float getMin() returns minimum value since last clear(). This value does not need to be in the internal buffer any more. Useful for graphing long term minima.
• float getMax() returns maximum value since last clear(). This value does not need to be in the internal buffer any more. Useful for graphing long term maxima.
• float getMinInBuffer() returns minimum value in the internal buffer.
• float getMaxInBuffer() returns maximum value in the internal buffer.

Admin functions

• bool bufferIsFull() returns true if buffer is full.
• uint16_t getSize() returns the size of the internal array.
• uint16_t getCount() returns the number of slots used of the internal array.

Helper functions

• float getElementValue(uint16_t index) get element directly from internal buffer at index.
• float getElementValue(uint16_t index) get element directly from internal buffer at index.
• float getSumValues() returns the sum of the values * weights in the internal buffer.
• float getSumWeights() returns the sum of the values in the internal buffer.

Future

Must

• update documentation
• keep in sync with RunningAverage

Should

• elaborate unit test

Could

• implement missing RunningAverage functions?

Wont

Support

If you appreciate my libraries, you can support the development and maintenance. Improve the quality of the libraries by providing issues and Pull Requests, or donate through PayPal or GitHub sponsors.

Thank you,