qmctorch.sampler.generalized_metropolis module

class qmctorch.sampler.generalized_metropolis.GeneralizedMetropolis(nwalkers=100, nstep=1000, step_size=3, ntherm=-1, ndecor=1, nelec=1, ndim=1, init={'max': 5, 'min': -5, 'type': 'uniform'}, cuda=False)

Bases: qmctorch.sampler.sampler_base.SamplerBase

Generalized Metropolis Hasting sampler

Parameters:

• nwalkers (int, optional) – number of walkers. Defaults to 100.
• nstep (int, optional) – number of steps. Defaults to 1000.
• step_size (int, optional) – size of the steps. Defaults to 3.
• ntherm (int, optional) – number of steps for thermalization. Defaults to -1.
• ndecor (int, optional) – number of steps for decorelation. Defaults to 1.
• nelec (int, optional) – number of electron. Defaults to 1.
• ndim (int, optional) – number of dimensions. Defaults to 1.
• init (dict, optional) – method to initialize the walkers. Defaults to {‘type’: ‘uniform’, ‘min’: -5, ‘max’: 5}.
• cuda (bool, optional) – use cuda. Defaults to False.

move(drift)

Move electron one at a time in a vectorized way.

Parameters:drift (torch.tensor) – drift velocity of the walkers Returns:new positions of the walkers Return type:torch.tensor

trans(xf, xi, drifti)

transform the positions

Parameters:

• xf ([type]) – [description]
• xi ([type]) – [description]
• drifti ([type]) – [description]

Returns:

[description]

Return type:

[type]

get_drift(pdf, x)

Compute the drift velocity

Parameters:

• pdf (callable) – function that returns the density
• x (torch.tensor) – positions of the walkers

Returns:

drift velocity

Return type:

torch.tensor