Struct Window 

pub struct Window<const N: usize> { /* private fields */ }

A fixed-capacity window over the most recent N readings.

Many field decisions look not at the latest reading but at the recent run of them: the lowest battery voltage in the last minute, the average flow over the last ten samples, how widely a tank level is bouncing. A Window keeps the last N readings in a ring buffer - no allocation, so it runs on a microcontroller - and reports their spread. It is the base the forecasting helpers build on.

The population variance is given directly; the standard deviation is its square root, left to the caller so the type stays dependency-free. Capacity N should be at least one; a zero-capacity window simply holds nothing.

Examples

use pamoja_kit::Window;

// Keep the last four tank-level readings and read their spread.
let mut levels = Window::<4>::new();
for reading in [40.0, 42.0, 38.0, 41.0] {
    levels.push(reading);
}
assert!(levels.is_full());
assert_eq!(levels.min(), Some(38.0));
assert_eq!(levels.max(), Some(42.0));
assert_eq!(levels.range(), Some(4.0));
assert_eq!(levels.latest(), Some(41.0));

Implementations

impl<const N: usize> Window<N>

pub fn new() -> Self

Creates an empty window with capacity N.

Returns

A window holding no readings yet.

pub fn push(&mut self, reading: f32)

Adds a reading, evicting the oldest once the window is full.

Arguments

• reading - the value to record.

pub fn len(&self) -> usize

Returns the number of readings currently held, at most N.

pub fn is_empty(&self) -> bool

Returns true if the window holds no readings.

pub fn is_full(&self) -> bool

Returns true if the window holds its full capacity of N readings.

pub fn capacity(&self) -> usize

Returns the window’s capacity, N.

pub fn latest(&self) -> Option<f32>

Returns the most recent reading, or None if the window is empty.

pub fn oldest(&self) -> Option<f32>

Returns the oldest reading still held, or None if the window is empty.

pub fn min(&self) -> Option<f32>

Returns the smallest reading in the window, or None if it is empty.

pub fn max(&self) -> Option<f32>

Returns the largest reading in the window, or None if it is empty.

pub fn range(&self) -> Option<f32>

Returns the spread (largest minus smallest), or None if the window is empty.

pub fn mean(&self) -> Option<f32>

Returns the mean of the readings, or None if the window is empty.

pub fn variance(&self) -> Option<f32>

Returns the population variance of the readings, or None if the window is empty.

Returns

The mean squared deviation from the mean. The standard deviation is its square root.

Trait Implementations

impl<const N: usize> Clone for Window<N>

fn clone(&self) -> Window<N>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<const N: usize> Copy for Window<N>

impl<const N: usize> Debug for Window<N>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<const N: usize> Default for Window<N>

fn default() -> Self

Returns the “default value” for a type.