TTOptions
TTOptions(
self,
tt_method: str = 'amen',
int_method: str = 'maxvol',
max_als: int = 1,
init_rank: int = 20,
kick_rank: int = 2,
max_rank: int = 30,
tol_svd: float = 0.0,
tol_max_core_error: float = 0.0,
tol_l2_error: float = 0.0,
verbose: int = 1,
)Options for configuring the construction of a TT object.
Parameters
tt_method : str = 'amen'-
The enrichment method used when constructing the TT cores. Can be
'fixed_rank'(no enrichment),'random', or'amen'(Dolgov and Savostyanov 2014). int_method : str = 'maxvol'-
The interpolation method used when constructing the tensor cores. Can be
'maxvol'(Goreinov et al. 2010) or'deim'(Chaturantabut and Sorensen 2010). max_als : int = 1-
The maximum number of ALS iterations to be carried out during the FTT construction.
init_rank : int = 20-
The initial rank of each tensor core.
kick_rank : int = 2-
The rank of the enrichment set of samples added at each ALS iteration.
max_rank : int = 30-
The maximum allowable rank of each tensor core (prior to the enrichment set being added).
tol_svd : float = 0.0-
The threshold to use when applying truncated SVD to the tensor cores when building the TT. The minimum number of singular values such that the sum of their squares exceeds (\(1-\)
tol_svd) will be retained. tol_max_core_error : float = 0.0-
A stopping tolerance, \(\epsilon\), based on the tensor cores. More concretely, if \(\boldsymbol{H}^{(\ell)}_{k}\) denotes the \(k\)th tensor core during sweep \(\ell\), the iterations are stopped if \[ \max_{k \in \{1, \dots, d\}} \frac{\|\boldsymbol{H}^{(\ell)}_{k}-\boldsymbol{H}^{(\ell-1)}_{k}\|_{\infty}} {\|\boldsymbol{H}^{(\ell)}_{k}\|_{\infty}} < \epsilon. \]
tol_l2_error : float = 0.0-
A stopping tolerance based on the estimated \(L^{2}\) error of the target function.
verbose : int = 1-
If
verbose=0, no information about the construction of the FTT will be printed. Ifverbose=1, diagnostic information will be prined at the end of each ALS iteration. Ifverbose=2, the tensor core currently being constructed during each ALS iteration will also be displayed.