Crate einops

Einops

This is a rust port of the incredible einops library. Almost all the operations specified in its tutorial should be available, if you find any inconsistencies please raise a github issue.

Unlike its python counterpart, caching the parsed expression has not been implemented yet. So when applying the same pattern multiple times, prefer Rearrange::new(...) or Rearrange::with_lengths(...) api, over the methods available through RearrangeFn like traits

Flexible and powerful tensor operations for readable and reliable code. Currently only supports tch.

Getting started

Add the following to your Cargo.toml file,

[dependencies]
einops = { version: "0.1", features: ["tch-bindings"] }

Examples

Einops provies three operations, they cover stacking, reshape, transposition, squeeze/unsqueeze, repeat, tile, concatenate and numerous reductions

// Tch specific imports
use tch::{Tensor, Kind, Device};
// Structs that provide constructor like api
use einops::{Rearrange, Repeat, Reduce, Operation, Backend};
// Traits required to call functions directly on the tensors
use einops::{ReduceFn, RearrangeFn, RepeatFn};

// We create a random tensor as input
let input = Tensor::randn(&[100, 32, 64], (Kind::Float, Device::Cpu));

// ------------------------------------------------------------------------
// Rearrange operation
let output = Rearrange::new("t b c -> b c t")?.apply(&input)?;
assert_eq!(output.size(), vec![32, 64, 100]);

// Apply rearrange operation directly on the tensor using `RearrangeFn` trait
let output = input.rearrange("t b c -> b c t")?;
assert_eq!(output.size(), vec![32, 64, 100]);

// ------------------------------------------------------------------------
// Perform reduction on first axis
let output = Reduce::new("t b c -> b c", Operation::Max)?.apply(&input)?;
assert_eq!(output.size(), vec![32, 64]);

// Same reduction done directly on the tensor using `ReduceFn` trait
let output = input.reduce("t b c -> b c", Operation::Max)?;
assert_eq!(output.size(), vec![32, 64]);

// ------------------------------------------------------------------------
// We repeat the third axis
let output = Repeat::new("t b c -> t b c 3")?.apply(&input)?;
assert_eq!(output.size(), vec![100, 32, 64, 3]);

// Same as above, but using `RepeatFn` trait and we specify the repeating
// axis with a name along with its size and pass it in a slice
let output = input.repeat_with_lengths("t b c -> t b c repeat", &[("repeat", 3)])?;
assert_eq!(output.size(), vec![100, 32, 64, 3]);

Structs

Rearrange	Reader-friendly reordering of tensors. Includes the functionality of transpose (axes permutation), reshape, squeeze, unsqueeze and other operations
Reduce	Provides combination of reordering and reduction using reader-friendly notation
Repeat	Repeat allows reordering elements and repeating them in arbitrary combinations. This includes functionality of repeat, tile, and broadcast functions

Enums

EinopsError	Different categories of error that can be encountered
Operation	Specifies the operation used to reduce an axis

Traits

RearrangeFn	Trait that allows calling the rearrange operation directly on the tensor
ReduceFn	Trait that allows calling the reduce operation directly on the tensor
RepeatFn	Trait that allows calling the repeat operation directly on the tensor