selectdim(path::EinExpr, index, i)

Project index to dimension i in a EinExpr. This is equivalent to tensor cutting aka slicing.


  • path Contraction path.
  • index Index to cut.
  • i Dimension of index to select.

See also: view.

view(path::EinExpr, cuttings...)

Project indices in contraction path to some of its dimensions. This is equivalent to:

reduce(cuttings) do path, (index, i)
    selectdim(path, index, i)


  • path Target contraction path.
  • cuttings List of Pair{Symbol,Int} representing the tensor cuttings aka slices.

See also: selectdim.

findslices(scorer, path::EinExpr; size, slices, overhead, temperature = 0.01, skip = head(path))

Search for indices to be cut/sliced such that the conditions given by size, overhead and slices are fulfilled. Reimplementation based on contengra's SliceFinder algorithm.


  • scorer Heuristic function (or functor) that accepts a path and a candidate index for cutting, and returns a score.
  • path The contraction path target for tensor cutting aka slicing.

Keyword Arguments

  • size If specified, the largest intermediate tensor of the slice won't surpass this size (in number of elements).
  • slices If specified, there will be at least slices different slices when cutting all returnt indices.
  • overhead If specified, the amount of redundant operations between a slice and the original contraction won't supass this ratio.
  • temperature Temperature of the Boltzmann-like noise added for diffusing results.
  • skip Indices not to be considered for slicing.