run¶

full name: tenpy.algorithms.dmrg.run
parent module: tenpy.algorithms.dmrg
type: function

tenpy.algorithms.dmrg.run(psi, model, options, **kwargs)[source]¶

Run the DMRG algorithm to find the ground state of the given model.

Parameters

psi (MPS) – Initial guess for the ground state, which is to be optimized in-place.
model (MPOModel) – The model representing the Hamiltonian for which we want to find the ground state.
options (dict) – Further optional parameters as described in DMRGEngine.
**kwargs – Further keyword arguments for the algorithm classes TwoSiteDMRGEngine or SingleSiteDMRGEngine.

Returns

info – A dictionary with keys 'E', 'shelve', 'bond_statistics', 'sweep_statistics'

Return type

dict

Options

config DMRG¶

option	summary
active_sites	The number of active sites to be used by DMRG. [...]
chi_list (from DMRGEngine) in DMRGEngine.reset_stats	A dictionary to gradually increase the `chi_max` parameter of [...]
chi_list_reactivates_mixer (from DMRGEngine) in DMRGEngine.sweep	If True, the mixer is reset/reactivated each time the bond dimension growth [...]
combine (from Sweep) in Sweep	Whether to combine legs into pipes. This combines the virtual and [...]
diag_method (from DMRGEngine) in DMRGEngine.run	Method to be used for diagonalzation, default ``'default'``. [...]
E_tol_max (from DMRGEngine) in DMRGEngine.run	See `E_tol_to_trunc`
E_tol_min (from DMRGEngine) in DMRGEngine.run	See `E_tol_to_trunc`
E_tol_to_trunc (from DMRGEngine) in DMRGEngine.run	It's reasonable to choose the Lanczos convergence criteria [...]
init_env_data (from Sweep) in DMRGEngine.init_env	Dictionary as returned by ``self.env.get_initialization_data()`` from [...]
lanczos_params (from Sweep) in Sweep	Lanczos parameters as described in :cfg:config:`Lanczos`.
max_E_err (from DMRGEngine) in DMRGEngine.run	Convergence if the change of the energy in each step [...]
max_hours (from DMRGEngine) in DMRGEngine.run	If the DMRG took longer (measured in wall-clock time), [...]
max_N_for_ED (from DMRGEngine) in DMRGEngine.diag	Maximum matrix dimension of the effective hamiltonian [...]
max_S_err (from DMRGEngine) in DMRGEngine.run	Convergence if the relative change of the entropy in each step [...]
max_sweeps (from DMRGEngine) in DMRGEngine.run	Maximum number of sweeps to be performed.
min_sweeps (from DMRGEngine) in DMRGEngine.run	Minimum number of sweeps to be performed. [...]
mixer (from DMRGEngine) in DMRGEngine.mixer_activate	Chooses the :class:`Mixer` to be used. [...]
mixer_params (from DMRGEngine) in DMRGEngine.mixer_activate	Mixer parameters as described in :cfg:config:`Mixer`.
N_sweeps_check (from DMRGEngine) in DMRGEngine.run	Number of sweeps to perform between checking convergence [...]
norm_tol (from DMRGEngine) in DMRGEngine.run	After the DMRG run, update the environment with at most [...]
norm_tol_final (from DMRGEngine) in DMRGEngine.run	After performing `norm_tol_iter`*`update_env` sweeps, if [...]
norm_tol_iter (from DMRGEngine) in DMRGEngine.run	Perform at most `norm_tol_iter`*`update_env` sweeps to [...]
orthogonal_to (from Sweep) in DMRGEngine.init_env	Deprecated in favor of the `orthogonal_to` function argument (forwarded fro [...]
P_tol_max (from DMRGEngine) in DMRGEngine.run	See `P_tol_to_trunc`
P_tol_min (from DMRGEngine) in DMRGEngine.run	See `P_tol_to_trunc`
P_tol_to_trunc (from DMRGEngine) in DMRGEngine.run	It's reasonable to choose the Lanczos convergence criteria [...]
start_env (from Sweep) in DMRGEngine.init_env	Number of sweeps to be performed without optimization to update the environment.
sweep_0 (from DMRGEngine) in DMRGEngine.reset_stats	The number of sweeps already performed. (Useful for re-start).
trunc_params (from Algorithm) in Algorithm	Truncation parameters as described in :cfg:config:`truncation`.
update_env (from DMRGEngine) in DMRGEngine.run	Number of sweeps without bond optimizaiton to update the [...]

option active_sites: 1 | 2¶: The number of active sites to be used by DMRG. If set to 1, SingleSiteDMRGEngine is used. If set to 2, DMRG is handled by TwoSiteDMRGEngine.