Struct ta::indicators::BollingerBands

pub struct BollingerBands { /* fields omitted */ }

A Bollinger Bands (BB). (BB). It is a type of infinite impulse response filter that calculates Bollinger Bands using Exponential Moving Average. The Bollinger Bands are represented by Average EMA and standard deviaton that is moved ‘k’ times away in both directions from calculated average value.

Formula

See SMA, SD documentation.

BB is composed as:

• BB_{Middle Band} - Simple Moving Average (SMA).
• BB_{Upper Band} = SMA + SD of observation * multipler (usually 2.0)
• BB_{Lower Band} = SMA - SD of observation * multipler (usually 2.0)

Example

 use ta::indicators::{BollingerBands, BollingerBandsOutput};
 use ta::Next;

 let mut bb = BollingerBands::new(3, 2.0_f64).unwrap();

 let out_0 = bb.next(2.0);

 let out_1 = bb.next(5.0);

 assert_eq!(out_0.average, 2.0);
 assert_eq!(out_0.upper, 2.0);
 assert_eq!(out_0.lower, 2.0);

 assert_eq!(out_1.average, 3.5);
 assert_eq!(out_1.upper, 6.5);
 assert_eq!(out_1.lower, 0.5);

Links

• Bollinger Bands, Wikipedia

Implementations

impl BollingerBands

pub fn new(period: usize, multiplier: f64) -> Result<Self>

pub fn multiplier(&self) -> f64

Trait Implementations

impl Clone for BollingerBands

fn clone(&self) -> BollingerBands

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for BollingerBands

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

Formats the value using the given formatter.

impl Default for BollingerBands

fn default() -> Self

Returns the “default value” for a type.

impl Display for BollingerBands

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

Formats the value using the given formatter.

impl<T: Close> Next<&'_ T> for BollingerBands

type Output = BollingerBandsOutput

fn next(&mut self, input: &T) -> Self::Output

impl Next<f64> for BollingerBands

type Output = BollingerBandsOutput

fn next(&mut self, input: f64) -> Self::Output

impl Period for BollingerBands

fn period(&self) -> usize

impl Reset for BollingerBands

fn reset(&mut self)