use super::{
expect_tensor, expect_tensor_mut, Data, Dimension, Forward, Gradient, Overwrite, Tensor,
};
use std::{
cell::{Cell, Ref, RefCell, RefMut},
fmt::{Debug, Display},
};
pub struct Input<D: Dimension> {
data: RefCell<Tensor<D>>,
computed: Cell<bool>,
}
impl<D: Dimension> Input<D> {
pub fn new(data: Tensor<D>) -> super::super::Var<Self> {
let input = Self {
data: RefCell::new(data),
computed: Cell::new(false),
};
super::super::Var::new(input)
}
pub(crate) fn differentiable(&self) -> InputBackward<D> {
InputBackward {
gradient: RefCell::new(Some(Tensor::zeros(self.data().raw_dim()))),
overwrite: Cell::new(true),
}
}
}
impl<D: Dimension> Data for Input<D> {
type Dim = D;
fn data(&self) -> Ref<Tensor<Self::Dim>> {
self.data.borrow()
}
fn data_mut(&self) -> RefMut<Tensor<Self::Dim>> {
self.data.borrow_mut()
}
}
impl<D: Dimension> Forward for Input<D> {
fn forward(&self) {
self.computed.set(true);
}
fn was_computed(&self) -> bool {
self.computed.get()
}
fn reset_computation(&self) {
self.computed.set(false);
}
}
impl<D: Dimension> Debug for Input<D> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.debug_struct("Input")
.field("data", &self.data.borrow())
.field("computed", &self.computed.get())
.finish()
}
}
impl<D: Dimension> Display for Input<D> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}", self.data.borrow())
}
}
pub struct InputBackward<D: Dimension> {
gradient: RefCell<Option<Tensor<D>>>,
overwrite: Cell<bool>,
}
impl<D: Dimension> InputBackward<D> {
pub fn zero_grad(&self) {
expect_tensor_mut(&self.gradient).fill(0.);
}
}
impl<D: Dimension> Gradient for InputBackward<D> {
type Dim = D;
fn gradient(&self) -> Ref<Tensor<Self::Dim>> {
expect_tensor(&self.gradient)
}
fn gradient_mut(&self) -> RefMut<Tensor<Self::Dim>> {
expect_tensor_mut(&self.gradient)
}
}
impl<D: Dimension> Overwrite for InputBackward<D> {
fn can_overwrite(&self) -> bool {
self.overwrite.get()
}
fn set_overwrite(&self, state: bool) {
self.overwrite.set(state);
}
}
impl<D: Dimension> Debug for InputBackward<D> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.debug_struct("InputBackward")
.field("gradient", &self.gradient.borrow())
.field("overwrite", &self.overwrite.get())
.finish()
}
}
impl<D: Dimension> Display for InputBackward<D> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match &*self.gradient.borrow() {
Some(gradient) => write!(f, "{}", &gradient),
None => write!(f, "None"),
}
}
}
#[cfg(test)]
mod test;