use crate::{KernelError, KernelMul, PositiveDefiniteKernel};
use opensrdk_symbolic_computation::Expression;
use std::fmt::Debug;
use std::{ops::Add, ops::Mul};
#[derive(Clone, Debug)]
pub struct KernelAdd<L, R>
where
L: PositiveDefiniteKernel,
R: PositiveDefiniteKernel,
{
lhs: L,
rhs: R,
}
impl<L, R> KernelAdd<L, R>
where
L: PositiveDefiniteKernel,
R: PositiveDefiniteKernel,
{
pub fn new(lhs: L, rhs: R) -> Self {
Self { lhs, rhs }
}
}
impl<L, R> PositiveDefiniteKernel for KernelAdd<L, R>
where
L: PositiveDefiniteKernel,
R: PositiveDefiniteKernel,
{
fn params_len(&self) -> usize {
self.lhs.params_len() + self.rhs.params_len()
}
fn expression(
&self,
x: Expression,
x_prime: Expression,
params: &[Expression],
) -> Result<Expression, KernelError> {
let lhs_params_len = self.lhs.params_len();
let fx = self
.lhs
.expression(x.clone(), x_prime.clone(), ¶ms[..lhs_params_len])?;
let gx = self.rhs.expression(x, x_prime, ¶ms[lhs_params_len..])?;
let hx = fx + gx;
Ok(hx)
}
}
impl<Rhs, L, R> Add<Rhs> for KernelAdd<L, R>
where
Rhs: PositiveDefiniteKernel,
L: PositiveDefiniteKernel,
R: PositiveDefiniteKernel,
{
type Output = KernelAdd<Self, Rhs>;
fn add(self, rhs: Rhs) -> Self::Output {
Self::Output::new(self, rhs)
}
}
impl<Rhs, L, R> Mul<Rhs> for KernelAdd<L, R>
where
Rhs: PositiveDefiniteKernel,
L: PositiveDefiniteKernel,
R: PositiveDefiniteKernel,
{
type Output = KernelMul<Self, Rhs>;
fn mul(self, rhs: Rhs) -> Self::Output {
Self::Output::new(self, rhs)
}
}