MINMAX

Library for finding peaks (minimum and maximum) in signal.

Description

The MINMAX library is a simple peak finder in a stream of floats.

It indicates if after adding a number the minimum and/or the maximum value has been changed by means of a bit flag that is returned. If a peak is found, it will be used as the new reference until a reset.

The library can reset the minimum and maximum to 0 to start again.

The library has also the option to auto-reset after a predefined number of add() calls.

Interface

MINMAX Constructor
uint8_t add(float value) add next value. Returns status (bit flags), see table below.
void reset() resets the minimum and maximum to 0.
void setAutoResetCount(uint32_t count) sets an auto-reset moment after count calls to add().
There will be at least one value processed.
uint32_t getAutoResetCount() returns set value.
float minimum() returns last minimum. Can be higher than previous call due to reset() or autoReset().
If no call to add() is made it will return 0.
float maximum() returns last maximum. Can be lower than previous call due to reset() or autoReset().
If no call to add() is made it will return 0.
uint32_t count() returns number of add() calls since last (auto)reset.

Return flags of add() - is a bitmask

flag	value	description
MINMAX_NO_CHANGE	0x00	no change
MINMAX_MIN_CHANGED	0x01	minimum changed
MINMAX_MAX_CHANGED	0x02	maximum changed
MINMAX_RESET_DONE	0x80	reset done

Obsolete

void autoReset(uint32_t count) obsolete, replaced by void setAutoResetCount()

Operation

The examples show the basic working of the functions.

Future

update documentation.
define FLAGS
add call back functions?
thresholds, windowing + triggers (separate class?)
auto-reset after time? (would affect all functions ?)
- need a uint32_t start;
- need a uint32_t threshold;
- millis() - start > threshold) => action.
Template class to allow other types
- int32_t uint64_t double etc.
- now you loose precision

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