Struct StratifiedShuffleSplit 

pub struct StratifiedShuffleSplit<L> { /* private fields */ }

Stratified random-permutation cross-validation.

Like ShuffleSplit, but every split keeps approximately the dataset’s class proportions in both its train and test subsets. Class labels are supplied at construction (generic L: Eq + Hash + Clone) and stored, so the splitter still satisfies the plain CvSplitter interface.

Per-class subset sizes are allocated proportionally and rounded, so realised sizes may differ from the requested totals by a sample or two — the guarantee is proportional balance, not an exact global count.

use ndarray::Array1;
use model_selection_rs::splitters::{CvSplitter, StratifiedShuffleSplit, SubsetSize};

let mut v = vec![0; 80];
v.extend(std::iter::repeat(1).take(20));
let y = Array1::from(v);
let sss = StratifiedShuffleSplit::new(3, &y)
    .with_test_size(SubsetSize::Fraction(0.2))
    .with_seed(0);
let splits = sss.split(100).unwrap();
assert_eq!(splits.len(), 3);

Implementations

impl<L: Eq + Hash + Clone> StratifiedShuffleSplit<L>

pub fn new(n_splits: usize, y: &Array1<L>) -> Self

Create a StratifiedShuffleSplit over class labels y, with a default test size of 10%.

pub fn with_test_size(self, test_size: SubsetSize) -> Self

Set the (approximate) total test-subset size.

pub fn with_train_size(self, train_size: SubsetSize) -> Self

Set the (approximate) total train-subset size.

pub fn with_seed(self, seed: u64) -> Self

Set the base RNG seed.

Trait Implementations

impl<L: Clone> Clone for StratifiedShuffleSplit<L>

fn clone(&self) -> StratifiedShuffleSplit<L>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<L: Eq + Hash + Clone> CvSplitter for StratifiedShuffleSplit<L>

fn split(&self, n_samples: usize) -> Result<Vec<(Vec<usize>, Vec<usize>)>>

Produce every (train_indices, test_indices) pair for n_samples rows.

fn n_splits(&self) -> usize

Number of splits this strategy yields.

impl<L: Debug> Debug for StratifiedShuffleSplit<L>

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

Formats the value using the given formatter.