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# 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 untila 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 f)** add next value. Returns status (bit flags), see table below.
- **void reset()** resets the minimum and maximum to 0.
- **void autoReset(uint32_t cnt)** sets an auto-reset moment after cnt calls to **add()**.  
There will be at least one value processed.
- **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 nr of **add()** calls since last (auto)reset.


Return values of **add()**

| flag | description     |
|:----:|:----------------|
| 0x00 | no change       |
| 0x01 | minimum changed |
| 0x02 | maximum changed |
| 0x80 | reset done      |


## 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)
-