Struct QuantileTransformer 

pub struct QuantileTransformer<F> { /* private fields */ }

An unfitted quantile transformer.

Calling Fit::fit computes the quantiles for each feature and returns a FittedQuantileTransformer.

Parameters

• n_quantiles — number of quantile reference points (default 1000).
• output_distribution — target distribution (default Uniform).
• subsample — maximum number of samples used to compute quantiles (default 100_000; set to 0 to use all samples).

Examples

use ferrolearn_preprocess::quantile_transformer::{QuantileTransformer, OutputDistribution};
use ferrolearn_core::traits::{Fit, Transform};
use ndarray::array;

let qt = QuantileTransformer::<f64>::new(100, OutputDistribution::Uniform, 0);
let x = array![[1.0], [2.0], [3.0], [4.0], [5.0]];
let fitted = qt.fit(&x, &()).unwrap();
let out = fitted.transform(&x).unwrap();
// Values should be in [0, 1]
for v in out.iter() {
    assert!(*v >= 0.0 && *v <= 1.0);
}

Implementations

impl<F: Float + Send + Sync + 'static> QuantileTransformer<F>

pub fn new( n_quantiles: usize, output_distribution: OutputDistribution, subsample: usize, ) -> Self

Create a new QuantileTransformer.

pub fn n_quantiles(&self) -> usize

Return the number of quantiles.

pub fn output_distribution(&self) -> OutputDistribution

Return the target output distribution.

pub fn subsample(&self) -> usize

Return the subsample size.

Trait Implementations

impl<F: Clone> Clone for QuantileTransformer<F>

fn clone(&self) -> QuantileTransformer<F>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<F: Debug> Debug for QuantileTransformer<F>

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

Formats the value using the given formatter.

impl<F: Float + Send + Sync + 'static> Default for QuantileTransformer<F>

fn default() -> Self

Returns the “default value” for a type.

impl<F: Float + Send + Sync + 'static> Fit<ArrayBase<OwnedRepr<F>, Dim<[usize; 2]>>, ()> for QuantileTransformer<F>

fn fit( &self, x: &Array2<F>, _y: &(), ) -> Result<FittedQuantileTransformer<F>, FerroError>

Fit by computing per-feature quantile reference values.

Errors

• FerroError::InsufficientSamples if the input has fewer than 2 rows.
• FerroError::InvalidParameter if n_quantiles is less than 2.

type Fitted = FittedQuantileTransformer<F>

The fitted model type returned by fit.

type Error = FerroError

The error type returned by fit.

impl<F: Float + Send + Sync + 'static> FitTransform<ArrayBase<OwnedRepr<F>, Dim<[usize; 2]>>> for QuantileTransformer<F>

fn fit_transform(&self, x: &Array2<F>) -> Result<Array2<F>, FerroError>

Fit and transform in one step.

Errors

Returns an error if fitting fails.

type FitError = FerroError

The error type for the combined fit-transform operation.

impl<F: Float + Send + Sync + 'static> Transform<ArrayBase<OwnedRepr<F>, Dim<[usize; 2]>>> for QuantileTransformer<F>

Implement Transform on the unfitted transformer to satisfy the FitTransform: Transform supertrait bound.

fn transform(&self, _x: &Array2<F>) -> Result<Array2<F>, FerroError>

Always returns an error — the transformer must be fitted first.

type Output = ArrayBase<OwnedRepr<F>, Dim<[usize; 2]>>

The transformed output type.

type Error = FerroError

The error type returned by transform.