Struct Fama 

pub struct Fama { /* private fields */ }

Scalar wrapper that exposes only the FAMA line from a Mama indicator.

FAMA (Following Adaptive Moving Average) is MAMA’s lagging companion in Ehlers’ MESA construction. It uses half MAMA’s adaptive alpha, so it reacts later than MAMA — MAMA crossing above FAMA marks a trend confirmation, MAMA below FAMA a reversal. See Mama for the joint (mama, fama) output; this wrapper exposes the slow line as a plain scalar indicator so it can be chained directly.

Example

use wickra_core::{Indicator, Fama};

let mut fama = Fama::new(0.5, 0.05).unwrap();
let mut last = None;
for i in 0..80 {
    last = fama.update(100.0 + (f64::from(i) * 0.3).sin() * 5.0);
}
assert!(last.is_some());

Implementations

impl Fama

pub fn new(fast_limit: f64, slow_limit: f64) -> Result<Self>

Construct with the same (fast_limit, slow_limit) semantics as Mama.

Errors

Forwards Mama::new’s validation errors.

pub fn classic() -> Self

Default (0.5, 0.05) parameters.

pub const fn limits(&self) -> (f64, f64)

Configured (fast_limit, slow_limit).

pub const fn value(&self) -> Option<f64>

Current FAMA value if available.

Trait Implementations

impl Clone for Fama

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Fama

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

Formats the value using the given formatter.

impl Indicator for Fama

type Input = f64

Type of one input data point (typically f64 for a price, or Candle / Tick).

type Output = f64

Type of one output value.

fn update(&mut self, input: f64) -> Option<f64>

Feed one new data point into the indicator and return the freshly computed output, or None if there is no value for this input.

fn reset(&mut self)

Reset all internal state, leaving the indicator equivalent to a freshly constructed instance with the same parameters.

fn warmup_period(&self) -> usize

Number of inputs required before the first non-None output can be produced.

fn is_ready(&self) -> bool

Whether the indicator has emitted at least one value since the last reset.

fn name(&self) -> &'static str

Stable, human-readable indicator name. Used by chaining and diagnostics.

fn batch_nan_into(&mut self, inputs: &[Self::Input], out: &mut [f64])

where Self::Input: Copy, Self::Output: Into<f64>,

Run the indicator over inputs, writing one output per input into the caller-owned out buffer (NaN where update returns None). It exists for every indicator whose output converts to an f64; the batch pipelines use it for the scalar f64 -> f64 ones.

fn batch_fast_into(&mut self, inputs: &[Self::Input], out: &mut [f64])

where Self::Input: Copy, Self::Output: Into<f64>,

Opt-in fast batch: like batch_nan_into, but an indicator with a vectorised kernel may reassociate its arithmetic to run it in SIMD lanes. Each value then agrees with the exact batch to within the tolerance the indicator documents (a few units in the last place), not bit for bit; warmup positions, NaN placement and the output length are identical. The kernels are deterministic: the same input produces the same bits on every platform, with or without SIMD hardware.