## TT-Toolbox 2.2.

TT-Toolbox (TT=Tensor Train) Version 2.2

TT(Tensor Train) format is an efficient way for low-parametric

representation of high-dimensional tensors. The TT-Toolbox

is a MATLAB implementation of basic operations with

tensors in TT-format. It includes:

* tt_tensor and tt_matrix classes for storing vectors and operators

* Basic linear algebra subroutines (addition, matrix-by-vector product,

elementwise multiplication and many others) using standard MATLAB syntax,

linear complexity in the dimension, reshape function

* Fast rounding procedure with a prescribed accuracy

* Advanced approximation and solution techniques:

* Approximate solution of linear systems and eigenvalue problems

* Cross methods to approximate “black-box” tensors

* Wavelet tensor train decomposition

* Construction of basic operators and functions (Laplace operator, function of a TT-tensor)

* Computation of maximal and minimal elements of a tensor

* and several others

New in Version 2.2

* Better documentation

* Mixed QTT-Tucker format (qtt_tucker class)

* reshape function for a TT-tensor/TT-matrix

* dmrg_cross method for black-box tensor approximation

* Convolution in QTT-format

**TT-Toolbox 2.2.**

If you are interested in getting the current “development” version of the Toolbox, take a look at the github repository http://github.com/oseledets/TT-Toolbox/