# ttclass/ttort.m

From Spinach Documentation Wiki

Performs TT-orthogonalisation for a tensor train (or for each tensor train in a buffered sum).

## Contents

## Syntax

[tt,lognrm]=ttort(tt,direct)

## Arguments

direct=+1 - {default} gives you left-to-right orthogonality, direct=-1 - gives right-to-left orthogonality tt - tensor train object, possibly with buffered sums

## Outputs

tt - tensor train object with all terms in the buffe- red sum has all of them orthogonalised in the direction requested lognrm - if this output is present, all buffered trains are also normalized, and natural logs of their norms returned in the vector lognrm. Use this option if the tensor norm is likely to exceed realmax()=1.7977e+308.

## Notes

Normally you should not call this subroutine directly.

## See also

*Version 2.1, authors: Ilya Kuprov, Dmitry Savostyanov*