ShapeSpace

class hoomd.hpmc.shape_move.ShapeSpace(callback, default_step_size=None, param_move_probability=1)

Bases: ShapeMove

Apply shape moves in a \(N\) dimensional shape space.

Parameters:

  • callback (callable [str, list], dict ]) – The python callable that will be called to map the given shape parameters to a shape definition. The callable takes the particle type and a list of parameters as arguments and return a dictionary with the shape definition whose keys must match the shape definition of the integrator: callable[[str, list], dict]. There is no type validation of the callback.

  • default_step_size (float, optional) – Default maximum size of shape trial moves (default: None). By default requires setting step size for all types.

  • param_move_probability (float, optional) – Average fraction of shape parameters to change each timestep (default: 1).

Shape support.

The following shapes are supported:

Attention

ShapeSpace only works with spheropolyhedra that have zero rounding or are spheres.

Note

Parameters must be given for every particle type and must be between 0 and 1. The class does not performs any consistency checks internally. Therefore, any shape constraint (e.g. constant volume, etc) must be performed within the callback.

Example:

mc = hoomd.hpmc.integrate.ConvexPolyhedron()
mc.shape["A"] = dict(vertices=[(1, 1, 1), (-1, -1, 1),
                               (1, -1, -1), (-1, 1, -1)])
# example callback
class ExampleCallback:
    def __init__(self):
        default_dict = dict(sweep_radius=0, ignore_statistics=True)
    def __call__(self, type, param_list):
        # do something with params and define verts
        return dict("vertices":verts, **self.default_dict))
move = hpmc.shape_move.ShapeSpace(callback = ExampleCallback)

Members inherited from ShapeMove:

step_size

Maximum size of the shape trial moves. Read more...

Members defined in ShapeSpace:

callback

The python function that will be called to map the given shape parameters to a shape definition. The function takes the particle type and a list of parameters as arguments and return a dictionary with the shape definition whose keys must match the shape definition of the integrator: callable[[str, list], dict].

Type:

callable [str, list], dict ]

params

List of tunable parameters to be updated. The length of the list defines the dimension of the shape space for each particle type.

Type:

TypeParameter [particle type, list]

param_move_probability

Average fraction of shape parameters to change each timestep (default: 1).

Type:

float, optional