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25 lines
1.1 KiB
Markdown
25 lines
1.1 KiB
Markdown
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# RunningMedian
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Arduino library to determine the running median by means of a circular buffer.
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## Description
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Running Median looks like a running average with a small but important twist.
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Running average averages the last N samples while the running median takes
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the last N samples, sort them and take the middle one, or the average of the middle two.
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Important differences between running average and running median:
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- Running median will return real data (e.g. a real sample from a sensor)
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if one uses an odd size of the buffer (preferred).
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Running average may return a value that is never sampled.
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- Running median will give zero weight to outliers, and 100% to the middle sample,
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whereas running average gives the same weight to all samples.
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- Running median will give often constant values for some time.
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- As one knows the values in the buffer one can predict to some extend how much
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the next samples will change the running median.
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- Running median is a bit harder as one needs to keep the values in order
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to remove the oldest and keep them sorted to be able to select the median.
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## Operation
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See examples
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