ttclass/amensum.m

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Tensor train summation without loss of accuracy.

Syntax

    y=amensum(x,tol,opts)

Description

Sums buffered tensor trains in a single tensor train using AMEn algorithm.

Arguments

   x   - ttclass with buffered rank-one tensors

   tol - relative tolerance parameter, e.g. 1e-10

The opts field is optional:

   opts.max_swp - maximum number of iterations

   opts.init_guess_rank - rank of the initial guess

   opts.enrichment_rank - rank of the enrichment

   opts.verb            - verbosity switch

Outputs

   y   - ttclass with a single tensor train, such
         that |x-y|<tol*|x| in Frobenius norm

Notes

Summation is a messy operation in TT format. Spinach buffers tensor train sums and processes them in batches using this function.

See also

ttclass.m, ttclass/plus.m, ttclass/pack.m


Version 2.1, authors: Dmitry Savostyanov, Sergey Dolgov