From Spinach Documentation Wiki
Solves the linear system Ax=y using the AMEn iteration.
x = amensolve(A,y,tol,opts,x0)
A very experimental tensor train format solver - see papers by Savostyanov and Dolgov.
A - ttclass representing a square matrix y - ttclass representing the right hand side tol - relative approximation and stopping tolerance, 1e-6 is a good start x0 - ttclass representing the initial guess Options (pass empty array for defaults): opts.nswp - maximum number of AMEn sweeps opts.init_guess_rank - the rank of the initial guess opts.enrichment_rank - the rank of the residual and enrichment opts.resid_damp - local accuracy gap opts.rmax - maximum TT rank limit for the solution opts.max_full_size - direct vs iterative solver switch- over dimension opts.local_iters - maximum number of bicgstab iterations for local problems opts.verb - Verbosity level: silent (0), sweep (1) or full (2)
x - ttclass representing the solution such that |x-X| < tol |X| in Frobenius norm, where X is the exact solution.
A, y and x0 should have ntrains==1. Call ttclass/shrink.m on all three if that is not the case.