SingleSiteMixer¶
full name: tenpy.algorithms.dmrg.SingleSiteMixer
parent module:
tenpy.algorithms.dmrg
type: class
Inheritance Diagram

Methods
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Preform a subspace expansion of a single-site wave function on one side. |
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Update the amplitude, possibly disable the mixer. |
Class Attributes and Properties
how many sites the theta in perturb_svd should have |
- class tenpy.algorithms.dmrg.SingleSiteMixer(*args, **kwargs)[source]¶
Bases:
SubspaceExpansion
Deprecated name for the
SubspaceExpansion
class.Deprecated since version 0.5.0: Instead of SingleSiteMixer and TwoSiteMixer, directly use
SubspaceExpansion
which is compatible with both single-site and two-site DMRG.- perturb_svd(engine, theta, i0, move_right)[source]¶
Preform a subspace expansion of a single-site wave function on one side.
- Parameters
engine (
DMRGEngine
) – The DMRG engine calling the mixer.theta (
Array
) – The optimized wave function, prepared for svd, with labels'(vL.p0)', 'vR'
for right move, or'vL', '(p0.vR)'
for left move.i0 (int) – The site index where theta lives.
move_right (bool | None) – Whether we move to the right (
True
), left (False
), or dont move (None
).
- Returns
U, VH (
Array
) – Left and right part of the subspace-expanded svd. Always such that the contractionU.S.VH
resembles the original theta up to truncation error. U has labels'(vL.p0)', 'vR'
(right move) or'vL', 'vR'
(left move). V has labels'vL', 'vR'
(right move) or'(vL.p0)', 'vR'
(left move). For a right move, only U is canonical; for a left-move only VH is canonical.S (1D ndarray) – (Perturbed) singular values on the new bond.
err (
TruncationError
) – The truncation error introduced.S_approx (ndarray) – Same as S.
- update_sites = 1¶
how many sites the theta in perturb_svd should have