Struct FunctionTransformer 

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

A stateless element-wise function transformer.

Wraps a boxed Fn(F) -> F closure and applies it to every element in the input matrix.

Examples

use ferrolearn_preprocess::function_transformer::FunctionTransformer;
use ferrolearn_core::traits::Transform;
use ndarray::array;

// Apply natural logarithm element-wise (values must be > 0)
let ft = FunctionTransformer::<f64>::new(|v| v.ln());
let x = array![[1.0, 2.0], [3.0, 4.0]];
let out = ft.transform(&x).unwrap();

Implementations

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

pub fn new<Func>(func: Func) -> Self

where Func: Fn(F) -> F + Send + Sync + 'static,

Create a new FunctionTransformer with the given function.

The function will be applied element-wise to the input matrix.

Trait Implementations

impl<F: Float + Send + Sync + 'static> Debug for FunctionTransformer<F>

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

Formats the value using the given formatter.

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

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

Apply the stored function to every element of x.

Errors

This implementation never returns an error for well-formed inputs. Note: if the user-provided function produces NaN or infinity for certain inputs, those values will appear in the output without error.

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

The transformed output type.

type Error = FerroError

The error type returned by transform.