feat: + cross_validate, trait Predictor, refactoring

This commit is contained in:
Volodymyr Orlov
2020-12-22 15:41:53 -08:00
parent 40dfca702e
commit a2be9e117f
34 changed files with 977 additions and 369 deletions
+286
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@@ -0,0 +1,286 @@
//! # KFold
//!
//! In statistics and machine learning we usually split our data into multiple subsets: training data and testing data (and sometimes to validate),
//! and fit our model on the train data, in order to make predictions on the test data. We do that to avoid overfitting or underfitting model to our data.
//! Overfitting is bad because the model we trained fits trained data too well and cant make any inferences on new data.
//! Underfitted is bad because the model is undetrained and does not fit the training data well.
//! Splitting data into multiple subsets helps to find the right combination of hyperparameters, estimate model performance and choose the right model for
//! your data.
//!
//! In SmartCore you can split your data into training and test datasets using `train_test_split` function.
use crate::linalg::Matrix;
use crate::math::num::RealNumber;
use rand::seq::SliceRandom;
use rand::thread_rng;
/// An interface for the K-Folds cross-validator
pub trait BaseKFold {
/// An iterator over indices that split data into training and test set.
type Output: Iterator<Item = (Vec<usize>, Vec<usize>)>;
/// Return a tuple containing the the training set indices for that split and
/// the testing set indices for that split.
fn split<T: RealNumber, M: Matrix<T>>(&self, x: &M) -> Self::Output;
/// Returns the number of splits
fn n_splits(&self) -> usize;
}
/// K-Folds cross-validator
pub struct KFold {
/// Number of folds. Must be at least 2.
pub n_splits: usize, // cannot exceed std::usize::MAX
/// Whether to shuffle the data before splitting into batches
pub shuffle: bool,
}
impl KFold {
fn test_indices<T: RealNumber, M: Matrix<T>>(&self, x: &M) -> Vec<Vec<usize>> {
// number of samples (rows) in the matrix
let n_samples: usize = x.shape().0;
// initialise indices
let mut indices: Vec<usize> = (0..n_samples).collect();
if self.shuffle {
indices.shuffle(&mut thread_rng());
}
// return a new array of given shape n_split, filled with each element of n_samples divided by n_splits.
let mut fold_sizes = vec![n_samples / self.n_splits; self.n_splits];
// increment by one if odd
for fold_size in fold_sizes.iter_mut().take(n_samples % self.n_splits) {
*fold_size += 1;
}
// generate the right array of arrays for test indices
let mut return_values: Vec<Vec<usize>> = Vec::with_capacity(self.n_splits);
let mut current: usize = 0;
for fold_size in fold_sizes.drain(..) {
let stop = current + fold_size;
return_values.push(indices[current..stop].to_vec());
current = stop
}
return_values
}
fn test_masks<T: RealNumber, M: Matrix<T>>(&self, x: &M) -> Vec<Vec<bool>> {
let mut return_values: Vec<Vec<bool>> = Vec::with_capacity(self.n_splits);
for test_index in self.test_indices(x).drain(..) {
// init mask
let mut test_mask = vec![false; x.shape().0];
// set mask's indices to true according to test indices
for i in test_index {
test_mask[i] = true; // can be implemented with map()
}
return_values.push(test_mask);
}
return_values
}
}
impl Default for KFold {
fn default() -> KFold {
KFold {
n_splits: 3,
shuffle: true,
}
}
}
impl KFold {
/// Number of folds. Must be at least 2.
pub fn with_n_splits(mut self, n_splits: usize) -> Self {
self.n_splits = n_splits;
self
}
/// Whether to shuffle the data before splitting into batches
pub fn with_shuffle(mut self, shuffle: bool) -> Self {
self.shuffle = shuffle;
self
}
}
/// An iterator over indices that split data into training and test set.
pub struct BaseKFoldIter {
indices: Vec<usize>,
test_indices: Vec<Vec<bool>>,
}
impl Iterator for BaseKFoldIter {
type Item = (Vec<usize>, Vec<usize>);
fn next(&mut self) -> Option<(Vec<usize>, Vec<usize>)> {
self.test_indices.pop().map(|test_index| {
let train_index = self
.indices
.iter()
.enumerate()
.filter(|&(idx, _)| !test_index[idx])
.map(|(idx, _)| idx)
.collect::<Vec<usize>>(); // filter train indices out according to mask
let test_index = self
.indices
.iter()
.enumerate()
.filter(|&(idx, _)| test_index[idx])
.map(|(idx, _)| idx)
.collect::<Vec<usize>>(); // filter tests indices out according to mask
(train_index, test_index)
})
}
}
/// Abstract class for all KFold functionalities
impl BaseKFold for KFold {
type Output = BaseKFoldIter;
fn n_splits(&self) -> usize {
self.n_splits
}
fn split<T: RealNumber, M: Matrix<T>>(&self, x: &M) -> Self::Output {
if self.n_splits < 2 {
panic!("Number of splits is too small: {}", self.n_splits);
}
let n_samples: usize = x.shape().0;
let indices: Vec<usize> = (0..n_samples).collect();
let mut test_indices = self.test_masks(x);
test_indices.reverse();
BaseKFoldIter {
indices,
test_indices,
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::linalg::naive::dense_matrix::*;
#[test]
fn run_kfold_return_test_indices_simple() {
let k = KFold {
n_splits: 3,
shuffle: false,
};
let x: DenseMatrix<f64> = DenseMatrix::rand(33, 100);
let test_indices = k.test_indices(&x);
assert_eq!(test_indices[0], (0..11).collect::<Vec<usize>>());
assert_eq!(test_indices[1], (11..22).collect::<Vec<usize>>());
assert_eq!(test_indices[2], (22..33).collect::<Vec<usize>>());
}
#[test]
fn run_kfold_return_test_indices_odd() {
let k = KFold {
n_splits: 3,
shuffle: false,
};
let x: DenseMatrix<f64> = DenseMatrix::rand(34, 100);
let test_indices = k.test_indices(&x);
assert_eq!(test_indices[0], (0..12).collect::<Vec<usize>>());
assert_eq!(test_indices[1], (12..23).collect::<Vec<usize>>());
assert_eq!(test_indices[2], (23..34).collect::<Vec<usize>>());
}
#[test]
fn run_kfold_return_test_mask_simple() {
let k = KFold {
n_splits: 2,
shuffle: false,
};
let x: DenseMatrix<f64> = DenseMatrix::rand(22, 100);
let test_masks = k.test_masks(&x);
for t in &test_masks[0][0..11] {
// TODO: this can be prob done better
assert_eq!(*t, true)
}
for t in &test_masks[0][11..22] {
assert_eq!(*t, false)
}
for t in &test_masks[1][0..11] {
assert_eq!(*t, false)
}
for t in &test_masks[1][11..22] {
assert_eq!(*t, true)
}
}
#[test]
fn run_kfold_return_split_simple() {
let k = KFold {
n_splits: 2,
shuffle: false,
};
let x: DenseMatrix<f64> = DenseMatrix::rand(22, 100);
let train_test_splits: Vec<(Vec<usize>, Vec<usize>)> = k.split(&x).collect();
assert_eq!(train_test_splits[0].1, (0..11).collect::<Vec<usize>>());
assert_eq!(train_test_splits[0].0, (11..22).collect::<Vec<usize>>());
assert_eq!(train_test_splits[1].0, (0..11).collect::<Vec<usize>>());
assert_eq!(train_test_splits[1].1, (11..22).collect::<Vec<usize>>());
}
#[test]
fn run_kfold_return_split_simple_shuffle() {
let k = KFold {
n_splits: 2,
..KFold::default()
};
let x: DenseMatrix<f64> = DenseMatrix::rand(23, 100);
let train_test_splits: Vec<(Vec<usize>, Vec<usize>)> = k.split(&x).collect();
assert_eq!(train_test_splits[0].1.len(), 12_usize);
assert_eq!(train_test_splits[0].0.len(), 11_usize);
assert_eq!(train_test_splits[1].0.len(), 12_usize);
assert_eq!(train_test_splits[1].1.len(), 11_usize);
}
#[test]
fn numpy_parity_test() {
let k = KFold {
n_splits: 3,
shuffle: false,
};
let x: DenseMatrix<f64> = DenseMatrix::rand(10, 4);
let expected: Vec<(Vec<usize>, Vec<usize>)> = vec![
(vec![4, 5, 6, 7, 8, 9], vec![0, 1, 2, 3]),
(vec![0, 1, 2, 3, 7, 8, 9], vec![4, 5, 6]),
(vec![0, 1, 2, 3, 4, 5, 6], vec![7, 8, 9]),
];
for ((train, test), (expected_train, expected_test)) in
k.split(&x).into_iter().zip(expected)
{
assert_eq!(test, expected_test);
assert_eq!(train, expected_train);
}
}
#[test]
fn numpy_parity_test_shuffle() {
let k = KFold {
n_splits: 3,
..KFold::default()
};
let x: DenseMatrix<f64> = DenseMatrix::rand(10, 4);
let expected: Vec<(Vec<usize>, Vec<usize>)> = vec![
(vec![4, 5, 6, 7, 8, 9], vec![0, 1, 2, 3]),
(vec![0, 1, 2, 3, 7, 8, 9], vec![4, 5, 6]),
(vec![0, 1, 2, 3, 4, 5, 6], vec![7, 8, 9]),
];
for ((train, test), (expected_train, expected_test)) in
k.split(&x).into_iter().zip(expected)
{
assert_eq!(test.len(), expected_test.len());
assert_eq!(train.len(), expected_train.len());
}
}
}
+238 -235
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@@ -9,21 +9,27 @@
//!
//! In SmartCore you can split your data into training and test datasets using `train_test_split` function.
use crate::base::Predictor;
use crate::error::Failed;
use crate::linalg::BaseVector;
use crate::linalg::Matrix;
use crate::math::num::RealNumber;
use crate::model_selection::kfold::BaseKFold;
use rand::seq::SliceRandom;
use rand::thread_rng;
use rand::Rng;
pub mod kfold;
/// Splits data into 2 disjoint datasets.
/// * `x` - features, matrix of size _NxM_ where _N_ is number of samples and _M_ is number of attributes.
/// * `y` - target values, should be of size _M_
/// * `test_size`, (0, 1] - the proportion of the dataset to include in the test split.
/// * `shuffle`, - whether or not to shuffle the data before splitting
pub fn train_test_split<T: RealNumber, M: Matrix<T>>(
x: &M,
y: &M::RowVector,
test_size: f32,
shuffle: bool,
) -> (M, M, M::RowVector, M::RowVector) {
if x.shape().0 != y.len() {
panic!(
@@ -38,155 +44,80 @@ pub fn train_test_split<T: RealNumber, M: Matrix<T>>(
}
let n = y.len();
let m = x.shape().1;
let mut rng = rand::thread_rng();
let mut n_test = 0;
let mut index = vec![false; n];
let n_test = ((n as f32) * test_size) as usize;
for index_i in index.iter_mut().take(n) {
let p_test: f32 = rng.gen();
if p_test <= test_size {
*index_i = true;
n_test += 1;
}
if n_test < 1 {
panic!("number of sample is too small {}", n);
}
let n_train = n - n_test;
let mut indices: Vec<usize> = (0..n).collect();
let mut x_train = M::zeros(n_train, m);
let mut x_test = M::zeros(n_test, m);
let mut y_train = M::RowVector::zeros(n_train);
let mut y_test = M::RowVector::zeros(n_test);
let mut r_train = 0;
let mut r_test = 0;
for (r, index_r) in index.iter().enumerate().take(n) {
if *index_r {
//sample belongs to test
for c in 0..m {
x_test.set(r_test, c, x.get(r, c));
y_test.set(r_test, y.get(r));
}
r_test += 1;
} else {
for c in 0..m {
x_train.set(r_train, c, x.get(r, c));
y_train.set(r_train, y.get(r));
}
r_train += 1;
}
if shuffle {
indices.shuffle(&mut thread_rng());
}
let x_train = x.take(&indices[n_test..n], 0);
let x_test = x.take(&indices[0..n_test], 0);
let y_train = y.take(&indices[n_test..n]);
let y_test = y.take(&indices[0..n_test]);
(x_train, x_test, y_train, y_test)
}
///
/// KFold Cross-Validation
///
pub trait BaseKFold {
/// Returns integer indices corresponding to test sets
fn test_indices<T: RealNumber, M: Matrix<T>>(&self, x: &M) -> Vec<Vec<usize>>;
/// Returns masksk corresponding to test sets
fn test_masks<T: RealNumber, M: Matrix<T>>(&self, x: &M) -> Vec<Vec<bool>>;
/// Return a tuple containing the the training set indices for that split and
/// the testing set indices for that split.
fn split<T: RealNumber, M: Matrix<T>>(&self, x: &M) -> Vec<(Vec<usize>, Vec<usize>)>;
#[derive(Clone, Debug)]
pub struct CrossValidationResult<T: RealNumber> {
pub test_score: Vec<T>,
pub train_score: Vec<T>,
}
///
/// An implementation of KFold
///
pub struct KFold {
n_splits: usize, // cannot exceed std::usize::MAX
shuffle: bool,
// TODO: to be implemented later
// random_state: i32,
}
impl<T: RealNumber> CrossValidationResult<T> {
pub fn mean_test_score(&self) -> T {
self.test_score.sum() / T::from_usize(self.test_score.len()).unwrap()
}
impl Default for KFold {
fn default() -> KFold {
KFold {
n_splits: 3_usize,
shuffle: true,
}
pub fn mean_train_score(&self) -> T {
self.train_score.sum() / T::from_usize(self.train_score.len()).unwrap()
}
}
///
/// Abstract class for all KFold functionalities
///
impl BaseKFold for KFold {
fn test_indices<T: RealNumber, M: Matrix<T>>(&self, x: &M) -> Vec<Vec<usize>> {
// number of samples (rows) in the matrix
let n_samples: usize = x.shape().0;
pub fn cross_validate<T, M, H, E, K, F, S>(
fit_estimator: F,
x: &M,
y: &M::RowVector,
parameters: H,
cv: K,
score: S,
) -> Result<CrossValidationResult<T>, Failed>
where
T: RealNumber,
M: Matrix<T>,
H: Clone,
E: Predictor<M, M::RowVector>,
K: BaseKFold,
F: Fn(&M, &M::RowVector, H) -> Result<E, Failed>,
S: Fn(&M::RowVector, &M::RowVector) -> T,
{
let k = cv.n_splits();
let mut test_score = Vec::with_capacity(k);
let mut train_score = Vec::with_capacity(k);
// initialise indices
let mut indices: Vec<usize> = (0..n_samples).collect();
if self.shuffle {
indices.shuffle(&mut thread_rng());
}
// return a new array of given shape n_split, filled with each element of n_samples divided by n_splits.
let mut fold_sizes = vec![n_samples / self.n_splits; self.n_splits];
for (test_idx, train_idx) in cv.split(x) {
let train_x = x.take(&train_idx, 0);
let train_y = y.take(&train_idx);
let test_x = x.take(&test_idx, 0);
let test_y = y.take(&test_idx);
// increment by one if odd
for fold_size in fold_sizes.iter_mut().take(n_samples % self.n_splits) {
*fold_size += 1;
}
let estimator = fit_estimator(&train_x, &train_y, parameters.clone())?;
// generate the right array of arrays for test indices
let mut return_values: Vec<Vec<usize>> = Vec::with_capacity(self.n_splits);
let mut current: usize = 0;
for fold_size in fold_sizes.drain(..) {
let stop = current + fold_size;
return_values.push(indices[current..stop].to_vec());
current = stop
}
return_values
train_score.push(score(&train_y, &estimator.predict(&train_x)?));
test_score.push(score(&test_y, &estimator.predict(&test_x)?));
}
fn test_masks<T: RealNumber, M: Matrix<T>>(&self, x: &M) -> Vec<Vec<bool>> {
let mut return_values: Vec<Vec<bool>> = Vec::with_capacity(self.n_splits);
for test_index in self.test_indices(x).drain(..) {
// init mask
let mut test_mask = vec![false; x.shape().0];
// set mask's indices to true according to test indices
for i in test_index {
test_mask[i] = true; // can be implemented with map()
}
return_values.push(test_mask);
}
return_values
}
fn split<T: RealNumber, M: Matrix<T>>(&self, x: &M) -> Vec<(Vec<usize>, Vec<usize>)> {
let n_samples: usize = x.shape().0;
let indices: Vec<usize> = (0..n_samples).collect();
let mut return_values: Vec<(Vec<usize>, Vec<usize>)> = Vec::with_capacity(self.n_splits); // TODO: init nested vecs with capacities by getting the length of test_index vecs
for test_index in self.test_masks(x).drain(..) {
let train_index = indices
.clone()
.iter()
.enumerate()
.filter(|&(idx, _)| !test_index[idx])
.map(|(idx, _)| idx)
.collect::<Vec<usize>>(); // filter train indices out according to mask
let test_index = indices
.iter()
.enumerate()
.filter(|&(idx, _)| test_index[idx])
.map(|(idx, _)| idx)
.collect::<Vec<usize>>(); // filter tests indices out according to mask
return_values.push((train_index, test_index))
}
return_values
}
Ok(CrossValidationResult {
test_score,
train_score,
})
}
#[cfg(test)]
@@ -194,14 +125,17 @@ mod tests {
use super::*;
use crate::linalg::naive::dense_matrix::*;
use crate::metrics::{accuracy, mean_absolute_error};
use crate::model_selection::kfold::KFold;
use crate::neighbors::knn_regressor::KNNRegressor;
#[test]
fn run_train_test_split() {
let n = 100;
let x: DenseMatrix<f64> = DenseMatrix::rand(100, 3);
let y = vec![0f64; 100];
let n = 123;
let x: DenseMatrix<f64> = DenseMatrix::rand(n, 3);
let y = vec![0f64; n];
let (x_train, x_test, y_train, y_test) = train_test_split(&x, &y, 0.2);
let (x_train, x_test, y_train, y_test) = train_test_split(&x, &y, 0.2, true);
assert!(
x_train.shape().0 > (n as f64 * 0.65) as usize
@@ -215,126 +149,195 @@ mod tests {
assert_eq!(x_test.shape().0, y_test.len());
}
#[test]
fn run_kfold_return_test_indices_simple() {
let k = KFold {
n_splits: 3,
shuffle: false,
};
let x: DenseMatrix<f64> = DenseMatrix::rand(33, 100);
let test_indices = k.test_indices(&x);
#[derive(Clone)]
struct NoParameters {}
assert_eq!(test_indices[0], (0..11).collect::<Vec<usize>>());
assert_eq!(test_indices[1], (11..22).collect::<Vec<usize>>());
assert_eq!(test_indices[2], (22..33).collect::<Vec<usize>>());
#[test]
fn test_cross_validate_biased() {
struct BiasedEstimator {}
impl BiasedEstimator {
fn fit<M: Matrix<f32>>(
_: &M,
_: &M::RowVector,
_: NoParameters,
) -> Result<BiasedEstimator, Failed> {
Ok(BiasedEstimator {})
}
}
impl<M: Matrix<f32>> Predictor<M, M::RowVector> for BiasedEstimator {
fn predict(&self, x: &M) -> Result<M::RowVector, Failed> {
let (n, _) = x.shape();
Ok(M::RowVector::zeros(n))
}
}
let x = DenseMatrix::from_2d_array(&[
&[5.1, 3.5, 1.4, 0.2],
&[4.9, 3.0, 1.4, 0.2],
&[4.7, 3.2, 1.3, 0.2],
&[4.6, 3.1, 1.5, 0.2],
&[5.0, 3.6, 1.4, 0.2],
&[5.4, 3.9, 1.7, 0.4],
&[4.6, 3.4, 1.4, 0.3],
&[5.0, 3.4, 1.5, 0.2],
&[4.4, 2.9, 1.4, 0.2],
&[4.9, 3.1, 1.5, 0.1],
&[7.0, 3.2, 4.7, 1.4],
&[6.4, 3.2, 4.5, 1.5],
&[6.9, 3.1, 4.9, 1.5],
&[5.5, 2.3, 4.0, 1.3],
&[6.5, 2.8, 4.6, 1.5],
&[5.7, 2.8, 4.5, 1.3],
&[6.3, 3.3, 4.7, 1.6],
&[4.9, 2.4, 3.3, 1.0],
&[6.6, 2.9, 4.6, 1.3],
&[5.2, 2.7, 3.9, 1.4],
]);
let y = vec![
0., 0., 0., 0., 0., 0., 0., 0., 1., 1., 1., 1., 1., 1., 1., 1., 1., 1., 1., 1.,
];
let cv = KFold {
n_splits: 5,
..KFold::default()
};
let results =
cross_validate(BiasedEstimator::fit, &x, &y, NoParameters {}, cv, &accuracy).unwrap();
assert_eq!(0.4, results.mean_test_score());
assert_eq!(0.4, results.mean_train_score());
}
#[test]
fn run_kfold_return_test_indices_odd() {
let k = KFold {
n_splits: 3,
shuffle: false,
};
let x: DenseMatrix<f64> = DenseMatrix::rand(34, 100);
let test_indices = k.test_indices(&x);
fn test_cross_validate_knn() {
let x = DenseMatrix::from_2d_array(&[
&[234.289, 235.6, 159., 107.608, 1947., 60.323],
&[259.426, 232.5, 145.6, 108.632, 1948., 61.122],
&[258.054, 368.2, 161.6, 109.773, 1949., 60.171],
&[284.599, 335.1, 165., 110.929, 1950., 61.187],
&[328.975, 209.9, 309.9, 112.075, 1951., 63.221],
&[346.999, 193.2, 359.4, 113.27, 1952., 63.639],
&[365.385, 187., 354.7, 115.094, 1953., 64.989],
&[363.112, 357.8, 335., 116.219, 1954., 63.761],
&[397.469, 290.4, 304.8, 117.388, 1955., 66.019],
&[419.18, 282.2, 285.7, 118.734, 1956., 67.857],
&[442.769, 293.6, 279.8, 120.445, 1957., 68.169],
&[444.546, 468.1, 263.7, 121.95, 1958., 66.513],
&[482.704, 381.3, 255.2, 123.366, 1959., 68.655],
&[502.601, 393.1, 251.4, 125.368, 1960., 69.564],
&[518.173, 480.6, 257.2, 127.852, 1961., 69.331],
&[554.894, 400.7, 282.7, 130.081, 1962., 70.551],
]);
let y = vec![
83.0, 88.5, 88.2, 89.5, 96.2, 98.1, 99.0, 100.0, 101.2, 104.6, 108.4, 110.8, 112.6,
114.2, 115.7, 116.9,
];
assert_eq!(test_indices[0], (0..12).collect::<Vec<usize>>());
assert_eq!(test_indices[1], (12..23).collect::<Vec<usize>>());
assert_eq!(test_indices[2], (23..34).collect::<Vec<usize>>());
let cv = KFold {
n_splits: 5,
..KFold::default()
};
let results = cross_validate(
KNNRegressor::fit,
&x,
&y,
Default::default(),
cv,
&mean_absolute_error,
)
.unwrap();
assert!(results.mean_test_score() < 15.0);
assert!(results.mean_train_score() < results.mean_test_score());
}
use crate::tree::decision_tree_regressor::*;
#[test]
fn run_kfold_return_test_mask_simple() {
let k = KFold {
n_splits: 2,
shuffle: false,
};
let x: DenseMatrix<f64> = DenseMatrix::rand(22, 100);
let test_masks = k.test_masks(&x);
fn test_some_regressor() {
let x = DenseMatrix::from_2d_array(&[
&[234.289, 235.6, 159., 107.608, 1947., 60.323],
&[259.426, 232.5, 145.6, 108.632, 1948., 61.122],
&[258.054, 368.2, 161.6, 109.773, 1949., 60.171],
&[284.599, 335.1, 165., 110.929, 1950., 61.187],
&[328.975, 209.9, 309.9, 112.075, 1951., 63.221],
&[346.999, 193.2, 359.4, 113.27, 1952., 63.639],
&[365.385, 187., 354.7, 115.094, 1953., 64.989],
&[363.112, 357.8, 335., 116.219, 1954., 63.761],
&[397.469, 290.4, 304.8, 117.388, 1955., 66.019],
&[419.18, 282.2, 285.7, 118.734, 1956., 67.857],
&[442.769, 293.6, 279.8, 120.445, 1957., 68.169],
&[444.546, 468.1, 263.7, 121.95, 1958., 66.513],
&[482.704, 381.3, 255.2, 123.366, 1959., 68.655],
&[502.601, 393.1, 251.4, 125.368, 1960., 69.564],
&[518.173, 480.6, 257.2, 127.852, 1961., 69.331],
&[554.894, 400.7, 282.7, 130.081, 1962., 70.551],
]);
let y = vec![
83.0, 88.5, 88.2, 89.5, 96.2, 98.1, 99.0, 100.0, 101.2, 104.6, 108.4, 110.8, 112.6,
114.2, 115.7, 116.9,
];
for t in &test_masks[0][0..11] {
// TODO: this can be prob done better
assert_eq!(*t, true)
}
for t in &test_masks[0][11..22] {
assert_eq!(*t, false)
}
let cv = KFold::default().with_n_splits(2);
for t in &test_masks[1][0..11] {
assert_eq!(*t, false)
}
for t in &test_masks[1][11..22] {
assert_eq!(*t, true)
}
let results = cross_validate(
DecisionTreeRegressor::fit,
&x,
&y,
Default::default(),
cv,
&mean_absolute_error,
)
.unwrap();
println!("{}", results.mean_test_score());
println!("{}", results.mean_train_score());
}
#[test]
fn run_kfold_return_split_simple() {
let k = KFold {
n_splits: 2,
shuffle: false,
};
let x: DenseMatrix<f64> = DenseMatrix::rand(22, 100);
let train_test_splits = k.split(&x);
assert_eq!(train_test_splits[0].1, (0..11).collect::<Vec<usize>>());
assert_eq!(train_test_splits[0].0, (11..22).collect::<Vec<usize>>());
assert_eq!(train_test_splits[1].0, (0..11).collect::<Vec<usize>>());
assert_eq!(train_test_splits[1].1, (11..22).collect::<Vec<usize>>());
}
use crate::tree::decision_tree_classifier::*;
#[test]
fn run_kfold_return_split_simple_shuffle() {
let k = KFold {
fn test_some_classifier() {
let x = DenseMatrix::from_2d_array(&[
&[5.1, 3.5, 1.4, 0.2],
&[4.9, 3.0, 1.4, 0.2],
&[4.7, 3.2, 1.3, 0.2],
&[4.6, 3.1, 1.5, 0.2],
&[5.0, 3.6, 1.4, 0.2],
&[5.4, 3.9, 1.7, 0.4],
&[4.6, 3.4, 1.4, 0.3],
&[5.0, 3.4, 1.5, 0.2],
&[4.4, 2.9, 1.4, 0.2],
&[4.9, 3.1, 1.5, 0.1],
&[7.0, 3.2, 4.7, 1.4],
&[6.4, 3.2, 4.5, 1.5],
&[6.9, 3.1, 4.9, 1.5],
&[5.5, 2.3, 4.0, 1.3],
&[6.5, 2.8, 4.6, 1.5],
&[5.7, 2.8, 4.5, 1.3],
&[6.3, 3.3, 4.7, 1.6],
&[4.9, 2.4, 3.3, 1.0],
&[6.6, 2.9, 4.6, 1.3],
&[5.2, 2.7, 3.9, 1.4],
]);
let y = vec![
0., 0., 0., 0., 0., 0., 0., 0., 1., 1., 1., 1., 1., 1., 1., 1., 1., 1., 1., 1.,
];
let cv = KFold {
n_splits: 2,
..KFold::default()
};
let x: DenseMatrix<f64> = DenseMatrix::rand(23, 100);
let train_test_splits = k.split(&x);
assert_eq!(train_test_splits[0].1.len(), 12_usize);
assert_eq!(train_test_splits[0].0.len(), 11_usize);
assert_eq!(train_test_splits[1].0.len(), 12_usize);
assert_eq!(train_test_splits[1].1.len(), 11_usize);
}
let results =
cross_validate(DecisionTreeClassifier::fit, &x, &y, Default::default(), cv, &accuracy).unwrap();
#[test]
fn numpy_parity_test() {
let k = KFold {
n_splits: 3,
shuffle: false,
};
let x: DenseMatrix<f64> = DenseMatrix::rand(10, 4);
let expected: Vec<(Vec<usize>, Vec<usize>)> = vec![
(vec![4, 5, 6, 7, 8, 9], vec![0, 1, 2, 3]),
(vec![0, 1, 2, 3, 7, 8, 9], vec![4, 5, 6]),
(vec![0, 1, 2, 3, 4, 5, 6], vec![7, 8, 9]),
];
for ((train, test), (expected_train, expected_test)) in
k.split(&x).into_iter().zip(expected)
{
assert_eq!(test, expected_test);
assert_eq!(train, expected_train);
}
}
#[test]
fn numpy_parity_test_shuffle() {
let k = KFold {
n_splits: 3,
..KFold::default()
};
let x: DenseMatrix<f64> = DenseMatrix::rand(10, 4);
let expected: Vec<(Vec<usize>, Vec<usize>)> = vec![
(vec![4, 5, 6, 7, 8, 9], vec![0, 1, 2, 3]),
(vec![0, 1, 2, 3, 7, 8, 9], vec![4, 5, 6]),
(vec![0, 1, 2, 3, 4, 5, 6], vec![7, 8, 9]),
];
for ((train, test), (expected_train, expected_test)) in
k.split(&x).into_iter().zip(expected)
{
assert_eq!(test.len(), expected_test.len());
assert_eq!(train.len(), expected_train.len());
}
println!("{}", results.mean_test_score());
println!("{}", results.mean_train_score());
}
}