TransformRecipe: TransformRecipe S3 constructor

In einops: Flexible, Powerful, and Readable Tensor Operations

TransformRecipe S3 constructor

Description

Recipe describes actual computation pathway. Can be applied to a tensor or variable.

Usage

TransformRecipe(
  elementary_axes_lengths,
  axis_name2elementary_axis,
  input_composition_known_unknown,
  axes_permutation,
  first_reduced_axis,
  added_axes,
  output_composite_axes
)

Arguments

elementary_axes_lengths	Integer vector. List of sizes for elementary axes as they appear in the input (left) expression. This is what (after computing unknown parts) will be a shape after first transposition. This does not include any ellipsis dimensions.
axis_name2elementary_axis	r2r::hashmap() Mapping from name to position. if additional axes are provided, they should be set in prev array. The keys are unclassed AxisNames() objects, and the values are integer positions of the elementary axes.
input_composition_known_unknown	List of list(known, unknown). known and unknown are integer vectors containing axis positions. These unknown and unknown integer vectors represent an unordered set and are always sorted to help with testing. ascending order for deterministic output.
axes_permutation	Integer vector. Permutation applied to elementary axes, if ellipsis is absent.
first_reduced_axis	Integer of length 1. First position of reduced axes. Permutation puts reduced axes in the end, we only need to know the first position.
added_axes	r2r::hashmap(). Axis position -> axis index. At which positions which of elementary axes should appear.
output_composite_axes	List of integer vectors. Ids of axes as they appear in result. Again pointers to elementary_axes_lengths, only used to infer result dimensions.

Value

An object of class 'TransformRecipe'.

einops documentation built on Sept. 9, 2025, 5:29 p.m.