* Update Cargo.toml * chore: fix clippy * chore: bump actions * chore: fix clippy * chore: update target name --------- Co-authored-by: Luis Moreno <morenol@users.noreply.github.com>
659 lines
22 KiB
Rust
659 lines
22 KiB
Rust
//! # Bernoulli Naive Bayes
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//!
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//! Bernoulli Naive Bayes classifier is a variant of [Naive Bayes](../index.html) for the data that is distributed according to multivariate Bernoulli distribution.
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//! It is used for discrete data with binary features. One example of a binary feature is a word that occurs in the text or not.
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//!
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//! Example:
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//!
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//! ```
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//! use smartcore::linalg::basic::matrix::DenseMatrix;
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//! use smartcore::naive_bayes::bernoulli::BernoulliNB;
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//!
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//! // Training data points are:
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//! // Chinese Beijing Chinese (class: China)
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//! // Chinese Chinese Shanghai (class: China)
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//! // Chinese Macao (class: China)
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//! // Tokyo Japan Chinese (class: Japan)
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//! let x = DenseMatrix::from_2d_array(&[
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//! &[1, 1, 0, 0, 0, 0],
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//! &[0, 1, 0, 0, 1, 0],
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//! &[0, 1, 0, 1, 0, 0],
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//! &[0, 1, 1, 0, 0, 1],
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//! ]).unwrap();
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//! let y: Vec<u32> = vec![0, 0, 0, 1];
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//!
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//! let nb = BernoulliNB::fit(&x, &y, Default::default()).unwrap();
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//!
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//! // Testing data point is:
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//! // Chinese Chinese Chinese Tokyo Japan
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//! let x_test = DenseMatrix::from_2d_array(&[&[0, 1, 1, 0, 0, 1]]).unwrap();
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//! let y_hat = nb.predict(&x_test).unwrap();
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//! ```
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//!
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//! ## References:
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//!
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//! * ["Introduction to Information Retrieval", Manning C. D., Raghavan P., Schutze H., 2009, Chapter 13 ](https://nlp.stanford.edu/IR-book/information-retrieval-book.html)
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use std::fmt;
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use num_traits::Unsigned;
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use crate::api::{Predictor, SupervisedEstimator};
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use crate::error::Failed;
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use crate::linalg::basic::arrays::{Array1, Array2, ArrayView1};
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use crate::naive_bayes::{BaseNaiveBayes, NBDistribution};
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use crate::numbers::basenum::Number;
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#[cfg(feature = "serde")]
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use serde::{Deserialize, Serialize};
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/// Naive Bayes classifier for Bearnoulli features
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#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
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#[derive(Debug, Clone)]
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struct BernoulliNBDistribution<T: Number + Ord + Unsigned> {
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/// class labels known to the classifier
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class_labels: Vec<T>,
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/// number of training samples observed in each class
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class_count: Vec<usize>,
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/// probability of each class
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class_priors: Vec<f64>,
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/// Number of samples encountered for each (class, feature)
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feature_count: Vec<Vec<usize>>,
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/// probability of features per class
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feature_log_prob: Vec<Vec<f64>>,
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/// Number of features of each sample
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n_features: usize,
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}
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impl<T: Number + Ord + Unsigned> fmt::Display for BernoulliNBDistribution<T> {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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writeln!(
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f,
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"BernoulliNBDistribution: n_features: {:?}",
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self.n_features
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)?;
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writeln!(f, "class_labels: {:?}", self.class_labels)?;
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Ok(())
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}
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}
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impl<T: Number + Ord + Unsigned> PartialEq for BernoulliNBDistribution<T> {
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fn eq(&self, other: &Self) -> bool {
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if self.class_labels == other.class_labels
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&& self.class_count == other.class_count
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&& self.class_priors == other.class_priors
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&& self.feature_count == other.feature_count
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&& self.n_features == other.n_features
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{
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for (a, b) in self
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.feature_log_prob
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.iter()
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.zip(other.feature_log_prob.iter())
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{
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if !a.iter().zip(b.iter()).all(|(a, b)| (a - b).abs() < 1e-4) {
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return false;
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}
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}
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true
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} else {
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false
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}
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}
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}
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impl<X: Number + PartialOrd, Y: Number + Ord + Unsigned> NBDistribution<X, Y>
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for BernoulliNBDistribution<Y>
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{
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fn prior(&self, class_index: usize) -> f64 {
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self.class_priors[class_index]
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}
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fn log_likelihood<'a>(&'a self, class_index: usize, j: &'a Box<dyn ArrayView1<X> + 'a>) -> f64 {
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let mut likelihood = 0f64;
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for feature in 0..j.shape() {
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let value = *j.get(feature);
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if value == X::one() {
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likelihood += self.feature_log_prob[class_index][feature];
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} else {
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likelihood += (1f64 - self.feature_log_prob[class_index][feature].exp()).ln();
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}
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}
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likelihood
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}
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fn classes(&self) -> &Vec<Y> {
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&self.class_labels
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}
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}
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/// `BernoulliNB` parameters. Use `Default::default()` for default values.
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#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
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#[derive(Debug, Clone)]
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pub struct BernoulliNBParameters<T: Number> {
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#[cfg_attr(feature = "serde", serde(default))]
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/// Additive (Laplace/Lidstone) smoothing parameter (0 for no smoothing).
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pub alpha: f64,
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#[cfg_attr(feature = "serde", serde(default))]
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/// Prior probabilities of the classes. If specified the priors are not adjusted according to the data
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pub priors: Option<Vec<f64>>,
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#[cfg_attr(feature = "serde", serde(default))]
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/// Threshold for binarizing (mapping to booleans) of sample features. If None, input is presumed to already consist of binary vectors.
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pub binarize: Option<T>,
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}
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impl<T: Number + PartialOrd> BernoulliNBParameters<T> {
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/// Additive (Laplace/Lidstone) smoothing parameter (0 for no smoothing).
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pub fn with_alpha(mut self, alpha: f64) -> Self {
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self.alpha = alpha;
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self
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}
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/// Prior probabilities of the classes. If specified the priors are not adjusted according to the data
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pub fn with_priors(mut self, priors: Vec<f64>) -> Self {
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self.priors = Some(priors);
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self
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}
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/// Threshold for binarizing (mapping to booleans) of sample features. If None, input is presumed to already consist of binary vectors.
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pub fn with_binarize(mut self, binarize: T) -> Self {
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self.binarize = Some(binarize);
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self
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}
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}
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impl<T: Number + PartialOrd> Default for BernoulliNBParameters<T> {
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fn default() -> Self {
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Self {
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alpha: 1f64,
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priors: Option::None,
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binarize: Some(T::zero()),
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}
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}
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}
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/// BernoulliNB grid search parameters
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#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
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#[derive(Debug, Clone)]
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pub struct BernoulliNBSearchParameters<T: Number> {
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#[cfg_attr(feature = "serde", serde(default))]
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/// Additive (Laplace/Lidstone) smoothing parameter (0 for no smoothing).
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pub alpha: Vec<f64>,
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#[cfg_attr(feature = "serde", serde(default))]
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/// Prior probabilities of the classes. If specified the priors are not adjusted according to the data
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pub priors: Vec<Option<Vec<f64>>>,
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#[cfg_attr(feature = "serde", serde(default))]
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/// Threshold for binarizing (mapping to booleans) of sample features. If None, input is presumed to already consist of binary vectors.
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pub binarize: Vec<Option<T>>,
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}
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/// BernoulliNB grid search iterator
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pub struct BernoulliNBSearchParametersIterator<T: Number> {
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bernoulli_nb_search_parameters: BernoulliNBSearchParameters<T>,
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current_alpha: usize,
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current_priors: usize,
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current_binarize: usize,
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}
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impl<T: Number> IntoIterator for BernoulliNBSearchParameters<T> {
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type Item = BernoulliNBParameters<T>;
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type IntoIter = BernoulliNBSearchParametersIterator<T>;
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fn into_iter(self) -> Self::IntoIter {
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BernoulliNBSearchParametersIterator {
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bernoulli_nb_search_parameters: self,
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current_alpha: 0,
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current_priors: 0,
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current_binarize: 0,
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}
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}
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}
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impl<T: Number> Iterator for BernoulliNBSearchParametersIterator<T> {
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type Item = BernoulliNBParameters<T>;
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fn next(&mut self) -> Option<Self::Item> {
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if self.current_alpha == self.bernoulli_nb_search_parameters.alpha.len()
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&& self.current_priors == self.bernoulli_nb_search_parameters.priors.len()
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&& self.current_binarize == self.bernoulli_nb_search_parameters.binarize.len()
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{
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return None;
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}
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let next = BernoulliNBParameters {
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alpha: self.bernoulli_nb_search_parameters.alpha[self.current_alpha],
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priors: self.bernoulli_nb_search_parameters.priors[self.current_priors].clone(),
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binarize: self.bernoulli_nb_search_parameters.binarize[self.current_binarize],
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};
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if self.current_alpha + 1 < self.bernoulli_nb_search_parameters.alpha.len() {
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self.current_alpha += 1;
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} else if self.current_priors + 1 < self.bernoulli_nb_search_parameters.priors.len() {
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self.current_alpha = 0;
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self.current_priors += 1;
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} else if self.current_binarize + 1 < self.bernoulli_nb_search_parameters.binarize.len() {
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self.current_alpha = 0;
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self.current_priors = 0;
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self.current_binarize += 1;
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} else {
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self.current_alpha += 1;
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self.current_priors += 1;
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self.current_binarize += 1;
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}
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Some(next)
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}
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}
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impl<T: Number + std::cmp::PartialOrd> Default for BernoulliNBSearchParameters<T> {
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fn default() -> Self {
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let default_params = BernoulliNBParameters::<T>::default();
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BernoulliNBSearchParameters {
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alpha: vec![default_params.alpha],
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priors: vec![default_params.priors],
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binarize: vec![default_params.binarize],
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}
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}
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}
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impl<TY: Number + Ord + Unsigned> BernoulliNBDistribution<TY> {
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/// Fits the distribution to a NxM matrix where N is number of samples and M is number of features.
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/// * `x` - training data.
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/// * `y` - vector with target values (classes) of length N.
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/// * `priors` - Optional vector with prior probabilities of the classes. If not defined, priors are adjusted according to the data.
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/// * `alpha` - Additive (Laplace/Lidstone) smoothing parameter.
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/// * `binarize` - Threshold for binarizing.
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fn fit<TX: Number + PartialOrd, X: Array2<TX>, Y: Array1<TY>>(
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x: &X,
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y: &Y,
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alpha: f64,
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priors: Option<Vec<f64>>,
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) -> Result<Self, Failed> {
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let (n_samples, n_features) = x.shape();
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let y_samples = y.shape();
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if y_samples != n_samples {
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return Err(Failed::fit(&format!(
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"Size of x should equal size of y; |x|=[{n_samples}], |y|=[{y_samples}]"
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)));
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}
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if n_samples == 0 {
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return Err(Failed::fit(&format!(
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"Size of x and y should greater than 0; |x|=[{n_samples}]"
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)));
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}
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if alpha < 0f64 {
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return Err(Failed::fit(&format!(
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"Alpha should be greater than 0; |alpha|=[{alpha}]"
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)));
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}
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let (class_labels, indices) = y.unique_with_indices();
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let mut class_count = vec![0_usize; class_labels.len()];
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for class_index in indices.iter() {
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class_count[*class_index] += 1;
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}
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let class_priors = if let Some(class_priors) = priors {
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if class_priors.len() != class_labels.len() {
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return Err(Failed::fit(
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"Size of priors provided does not match the number of classes of the data.",
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));
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}
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class_priors
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} else {
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class_count
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.iter()
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.map(|&c| c as f64 / (n_samples as f64))
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.collect()
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};
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let mut feature_in_class_counter = vec![vec![0_usize; n_features]; class_labels.len()];
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for (row, class_index) in x.row_iter().zip(indices) {
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for (idx, row_i) in row.iterator(0).enumerate().take(n_features) {
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feature_in_class_counter[class_index][idx] +=
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row_i.to_usize().ok_or_else(|| {
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Failed::fit(&format!(
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"Elements of the matrix should be 1.0 or 0.0 |found|=[{row_i}]"
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))
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})?;
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}
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}
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let feature_log_prob = feature_in_class_counter
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.iter()
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.enumerate()
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.map(|(class_index, feature_count)| {
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feature_count
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.iter()
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.map(|&count| {
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((count as f64 + alpha) / (class_count[class_index] as f64 + alpha * 2f64))
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.ln()
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})
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.collect()
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})
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.collect();
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Ok(Self {
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class_labels,
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class_priors,
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class_count,
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feature_count: feature_in_class_counter,
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feature_log_prob,
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n_features,
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})
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}
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}
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/// BernoulliNB implements the naive Bayes algorithm for data that follows the Bernoulli
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/// distribution.
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#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
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#[derive(Debug, PartialEq)]
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pub struct BernoulliNB<
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TX: Number + PartialOrd,
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TY: Number + Ord + Unsigned,
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X: Array2<TX>,
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Y: Array1<TY>,
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> {
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inner: Option<BaseNaiveBayes<TX, TY, X, Y, BernoulliNBDistribution<TY>>>,
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binarize: Option<TX>,
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}
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impl<TX: Number + PartialOrd, TY: Number + Ord + Unsigned, X: Array2<TX>, Y: Array1<TY>>
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fmt::Display for BernoulliNB<TX, TY, X, Y>
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{
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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writeln!(
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f,
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"BernoulliNB:\ninner: {:?}\nbinarize: {:?}",
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self.inner.as_ref().unwrap(),
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self.binarize.as_ref().unwrap()
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)?;
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Ok(())
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}
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}
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impl<TX: Number + PartialOrd, TY: Number + Ord + Unsigned, X: Array2<TX>, Y: Array1<TY>>
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SupervisedEstimator<X, Y, BernoulliNBParameters<TX>> for BernoulliNB<TX, TY, X, Y>
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{
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fn new() -> Self {
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Self {
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inner: Option::None,
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binarize: Option::None,
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}
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}
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fn fit(x: &X, y: &Y, parameters: BernoulliNBParameters<TX>) -> Result<Self, Failed> {
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BernoulliNB::fit(x, y, parameters)
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}
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}
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impl<TX: Number + PartialOrd, TY: Number + Ord + Unsigned, X: Array2<TX>, Y: Array1<TY>>
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Predictor<X, Y> for BernoulliNB<TX, TY, X, Y>
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{
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fn predict(&self, x: &X) -> Result<Y, Failed> {
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self.predict(x)
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}
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}
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impl<TX: Number + PartialOrd, TY: Number + Ord + Unsigned, X: Array2<TX>, Y: Array1<TY>>
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BernoulliNB<TX, TY, X, Y>
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{
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/// Fits BernoulliNB with given data
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/// * `x` - training data of size NxM where N is the number of samples and M is the number of
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/// features.
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/// * `y` - vector with target values (classes) of length N.
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/// * `parameters` - additional parameters like class priors, alpha for smoothing and
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/// binarizing threshold.
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pub fn fit(x: &X, y: &Y, parameters: BernoulliNBParameters<TX>) -> Result<Self, Failed> {
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let distribution = if let Some(threshold) = parameters.binarize {
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BernoulliNBDistribution::fit(
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&Self::binarize(x, threshold),
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y,
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parameters.alpha,
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parameters.priors,
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)?
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} else {
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BernoulliNBDistribution::fit(x, y, parameters.alpha, parameters.priors)?
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};
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let inner = BaseNaiveBayes::fit(distribution)?;
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Ok(Self {
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inner: Some(inner),
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binarize: parameters.binarize,
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})
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}
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/// Estimates the class labels for the provided data.
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/// * `x` - data of shape NxM where N is number of data points to estimate and M is number of features.
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///
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/// Returns a vector of size N with class estimates.
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pub fn predict(&self, x: &X) -> Result<Y, Failed> {
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if let Some(threshold) = self.binarize {
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self.inner
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.as_ref()
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.unwrap()
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.predict(&Self::binarize(x, threshold))
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} else {
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self.inner.as_ref().unwrap().predict(x)
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}
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}
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/// Class labels known to the classifier.
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/// Returns a vector of size n_classes.
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pub fn classes(&self) -> &Vec<TY> {
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&self.inner.as_ref().unwrap().distribution.class_labels
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}
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/// Number of training samples observed in each class.
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/// Returns a vector of size n_classes.
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pub fn class_count(&self) -> &Vec<usize> {
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&self.inner.as_ref().unwrap().distribution.class_count
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}
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/// Number of features of each sample
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pub fn n_features(&self) -> usize {
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self.inner.as_ref().unwrap().distribution.n_features
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}
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/// Number of samples encountered for each (class, feature)
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/// Returns a 2d vector of shape (n_classes, n_features)
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pub fn feature_count(&self) -> &Vec<Vec<usize>> {
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&self.inner.as_ref().unwrap().distribution.feature_count
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}
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/// Empirical log probability of features given a class
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pub fn feature_log_prob(&self) -> &Vec<Vec<f64>> {
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&self.inner.as_ref().unwrap().distribution.feature_log_prob
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}
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fn binarize_mut(x: &mut X, threshold: TX) {
|
|
let (nrows, ncols) = x.shape();
|
|
for row in 0..nrows {
|
|
for col in 0..ncols {
|
|
if *x.get((row, col)) > threshold {
|
|
x.set((row, col), TX::one());
|
|
} else {
|
|
x.set((row, col), TX::zero());
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn binarize(x: &X, threshold: TX) -> X {
|
|
let mut new_x = x.clone();
|
|
Self::binarize_mut(&mut new_x, threshold);
|
|
new_x
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
use crate::linalg::basic::matrix::DenseMatrix;
|
|
|
|
#[test]
|
|
fn search_parameters() {
|
|
let parameters: BernoulliNBSearchParameters<f64> = BernoulliNBSearchParameters {
|
|
alpha: vec![1., 2.],
|
|
..Default::default()
|
|
};
|
|
let mut iter = parameters.into_iter();
|
|
let next = iter.next().unwrap();
|
|
assert_eq!(next.alpha, 1.);
|
|
let next = iter.next().unwrap();
|
|
assert_eq!(next.alpha, 2.);
|
|
assert!(iter.next().is_none());
|
|
}
|
|
|
|
#[cfg_attr(
|
|
all(target_arch = "wasm32", not(target_os = "wasi")),
|
|
wasm_bindgen_test::wasm_bindgen_test
|
|
)]
|
|
#[test]
|
|
fn run_bernoulli_naive_bayes() {
|
|
// Tests that BernoulliNB when alpha=1.0 gives the same values as
|
|
// those given for the toy example in Manning, Raghavan, and
|
|
// Schuetze's "Introduction to Information Retrieval" book:
|
|
// https://nlp.stanford.edu/IR-book/html/htmledition/the-bernoulli-model-1.html
|
|
|
|
// Training data points are:
|
|
// Chinese Beijing Chinese (class: China)
|
|
// Chinese Chinese Shanghai (class: China)
|
|
// Chinese Macao (class: China)
|
|
// Tokyo Japan Chinese (class: Japan)
|
|
let x = DenseMatrix::from_2d_array(&[
|
|
&[1.0, 1.0, 0.0, 0.0, 0.0, 0.0],
|
|
&[0.0, 1.0, 0.0, 0.0, 1.0, 0.0],
|
|
&[0.0, 1.0, 0.0, 1.0, 0.0, 0.0],
|
|
&[0.0, 1.0, 1.0, 0.0, 0.0, 1.0],
|
|
])
|
|
.unwrap();
|
|
let y: Vec<u32> = vec![0, 0, 0, 1];
|
|
let bnb = BernoulliNB::fit(&x, &y, Default::default()).unwrap();
|
|
|
|
let distribution = bnb.inner.clone().unwrap().distribution;
|
|
|
|
assert_eq!(&distribution.class_priors, &[0.75, 0.25]);
|
|
assert_eq!(
|
|
bnb.feature_log_prob(),
|
|
&[
|
|
&[
|
|
-0.916290731874155,
|
|
-0.2231435513142097,
|
|
-1.6094379124341003,
|
|
-0.916290731874155,
|
|
-0.916290731874155,
|
|
-1.6094379124341003
|
|
],
|
|
&[
|
|
-1.0986122886681098,
|
|
-0.40546510810816444,
|
|
-0.40546510810816444,
|
|
-1.0986122886681098,
|
|
-1.0986122886681098,
|
|
-0.40546510810816444
|
|
]
|
|
]
|
|
);
|
|
|
|
// Testing data point is:
|
|
// Chinese Chinese Chinese Tokyo Japan
|
|
let x_test = DenseMatrix::from_2d_array(&[&[0.0, 1.0, 1.0, 0.0, 0.0, 1.0]]).unwrap();
|
|
let y_hat = bnb.predict(&x_test).unwrap();
|
|
|
|
assert_eq!(y_hat, &[1]);
|
|
}
|
|
|
|
#[cfg_attr(
|
|
all(target_arch = "wasm32", not(target_os = "wasi")),
|
|
wasm_bindgen_test::wasm_bindgen_test
|
|
)]
|
|
#[test]
|
|
fn bernoulli_nb_scikit_parity() {
|
|
let x = DenseMatrix::from_2d_array(&[
|
|
&[2, 4, 0, 0, 2, 1, 2, 4, 2, 0],
|
|
&[3, 4, 0, 2, 1, 0, 1, 4, 0, 3],
|
|
&[1, 4, 2, 4, 1, 0, 1, 2, 3, 2],
|
|
&[0, 3, 3, 4, 1, 0, 3, 1, 1, 1],
|
|
&[0, 2, 1, 4, 3, 4, 1, 2, 3, 1],
|
|
&[3, 2, 4, 1, 3, 0, 2, 4, 0, 2],
|
|
&[3, 1, 3, 0, 2, 0, 4, 4, 3, 4],
|
|
&[2, 2, 2, 0, 1, 1, 2, 1, 0, 1],
|
|
&[3, 3, 2, 2, 0, 2, 3, 2, 2, 3],
|
|
&[4, 3, 4, 4, 4, 2, 2, 0, 1, 4],
|
|
&[3, 4, 2, 2, 1, 4, 4, 4, 1, 3],
|
|
&[3, 0, 1, 4, 4, 0, 0, 3, 2, 4],
|
|
&[2, 0, 3, 3, 1, 2, 0, 2, 4, 1],
|
|
&[2, 4, 0, 4, 2, 4, 1, 3, 1, 4],
|
|
&[0, 2, 2, 3, 4, 0, 4, 4, 4, 4],
|
|
])
|
|
.unwrap();
|
|
let y: Vec<u32> = vec![2, 2, 0, 0, 0, 2, 1, 1, 0, 1, 0, 0, 2, 0, 2];
|
|
let bnb = BernoulliNB::fit(&x, &y, Default::default()).unwrap();
|
|
|
|
let y_hat = bnb.predict(&x).unwrap();
|
|
|
|
assert_eq!(bnb.classes(), &[0, 1, 2]);
|
|
assert_eq!(bnb.class_count(), &[7, 3, 5]);
|
|
assert_eq!(bnb.n_features(), 10);
|
|
assert_eq!(
|
|
bnb.feature_count(),
|
|
&[
|
|
&[5, 6, 6, 7, 6, 4, 6, 7, 7, 7],
|
|
&[3, 3, 3, 1, 3, 2, 3, 2, 2, 3],
|
|
&[4, 4, 3, 4, 5, 2, 4, 5, 3, 4]
|
|
]
|
|
);
|
|
|
|
// test Display
|
|
println!("{}", &bnb);
|
|
|
|
let distribution = bnb.inner.clone().unwrap().distribution;
|
|
|
|
assert_eq!(
|
|
&distribution.class_priors,
|
|
&vec!(0.4666666666666667, 0.2, 0.3333333333333333)
|
|
);
|
|
assert_eq!(
|
|
&bnb.feature_log_prob()[1],
|
|
&vec![
|
|
-0.2231435513142097,
|
|
-0.2231435513142097,
|
|
-0.2231435513142097,
|
|
-0.916290731874155,
|
|
-0.2231435513142097,
|
|
-0.5108256237659907,
|
|
-0.2231435513142097,
|
|
-0.5108256237659907,
|
|
-0.5108256237659907,
|
|
-0.2231435513142097
|
|
]
|
|
);
|
|
assert_eq!(y_hat, vec!(2, 2, 0, 0, 0, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0));
|
|
}
|
|
|
|
#[cfg_attr(
|
|
all(target_arch = "wasm32", not(target_os = "wasi")),
|
|
wasm_bindgen_test::wasm_bindgen_test
|
|
)]
|
|
#[test]
|
|
#[cfg(feature = "serde")]
|
|
fn serde() {
|
|
let x = DenseMatrix::from_2d_array(&[
|
|
&[1, 1, 0, 0, 0, 0],
|
|
&[0, 1, 0, 0, 1, 0],
|
|
&[0, 1, 0, 1, 0, 0],
|
|
&[0, 1, 1, 0, 0, 1],
|
|
])
|
|
.unwrap();
|
|
let y: Vec<u32> = vec![0, 0, 0, 1];
|
|
|
|
let bnb = BernoulliNB::fit(&x, &y, Default::default()).unwrap();
|
|
let deserialized_bnb: BernoulliNB<i32, u32, DenseMatrix<i32>, Vec<u32>> =
|
|
serde_json::from_str(&serde_json::to_string(&bnb).unwrap()).unwrap();
|
|
|
|
assert_eq!(bnb, deserialized_bnb);
|
|
}
|
|
}
|