Struct linfa_bayes::MultinomialNb

pub struct MultinomialNb<F: PartialEq, L: Eq + Hash> { /* private fields */ }

Fitted Multinomial Naive Bayes classifier.

See MultinomialNbParams for more information on the hyper-parameters.

Model assumptions

The family of Naive Bayes classifiers assume independence between variables. They do not model moments between variables and lack therefore in modelling capability. The advantage is a linear fitting time with maximum-likelihood training in a closed form.

Model usage example

The example below creates a set of hyperparameters, and then uses it to fit a Multinomial Naive Bayes classifier on provided data.

use linfa_bayes::{MultinomialNbParams, MultinomialNbValidParams, Result};
use linfa::prelude::*;
use ndarray::array;

let x = array![
    [-2., -1.],
    [-1., -1.],
    [-1., -2.],
    [1., 1.],
    [1., 2.],
    [2., 1.]
];
let y = array![1, 1, 1, 2, 2, 2];
let ds = DatasetView::new(x.view(), y.view());

// create a new parameter set with smoothing parameter equals `1`
let unchecked_params = MultinomialNbParams::new()
    .alpha(1.0);

// fit model with unchecked parameter set
let model = unchecked_params.fit(&ds)?;

// transform into a verified parameter set
let checked_params = unchecked_params.check()?;

// update model with the verified parameters, this only returns
// errors originating from the fitting process
let model = checked_params.fit_with(Some(model), &ds)?;

Implementations

impl<F: Float, L: Label> MultinomialNb<F, L>

pub fn params() -> MultinomialNbParams<F, L>

Construct a new set of hyperparameters

Trait Implementations

impl<F: Clone + PartialEq, L: Clone + Eq + Hash> Clone for MultinomialNb<F, L>

fn clone(&self) -> MultinomialNb<F, L>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<F: Debug + PartialEq, L: Debug + Eq + Hash> Debug for MultinomialNb<F, L>

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

Formats the value using the given formatter.

impl<F: PartialEq + PartialEq, L: PartialEq + Eq + Hash> PartialEq for MultinomialNb<F, L>

fn eq(&self, other: &MultinomialNb<F, L>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<F: Float, L: Label, D> PredictInplace<ArrayBase<D, Dim<[usize; 2]>>, ArrayBase<OwnedRepr<L>, Dim<[usize; 1]>>> for MultinomialNb<F, L>where D: Data<Elem = F>,

fn predict_inplace(&self, x: &ArrayBase<D, Ix2>, y: &mut Array1<L>)

Predict something in place

fn default_target(&self, x: &ArrayBase<D, Ix2>) -> Array1<L>

Create targets that predict_inplace works with.

impl<F: PartialEq, L: Eq + Hash> StructuralPartialEq for MultinomialNb<F, L>