def rigid():
R""" Groups particles that belong to rigid bodies.
Creates a particle group from particles. All particles that belong to a rigid body will be added to the group.
The group is always named 'rigid'.
Examples::
rigid = group.rigid()
"""
hoomd.util.print_status_line()
# check if initialization has occurred
if not hoomd.init.is_initialized():
hoomd.context.msg.error(
"Cannot create a group before initialization\n")
raise RuntimeError('Error creating group')
# create the group
name = 'rigid'
selector = _hoomd.ParticleSelectorRigid(
hoomd.context.current.system_definition, True)
cpp_group = _hoomd.ParticleGroup(hoomd.context.current.system_definition,
selector)
# notify the user of the created group
hoomd.context.msg.notice(
2, 'Group "' + name + '" created containing ' +
str(cpp_group.getNumMembersGlobal()) + ' particles\n')
# return it in the wrapper class
return group(name, cpp_group)
def nonrigid():
R""" Groups particles that do not belong to rigid bodies.
Creates a particle group from particles. All particles that **do not** belong to a rigid body will be added to
the group. The group is always named 'nonrigid'.
Examples::
nonrigid = group.nonrigid()
"""
# check if initialization has occurred
if not hoomd.init.is_initialized():
raise RuntimeError('Cannot create a group before initialization\n');
# create the group
name = 'nonrigid';
selector = _hoomd.ParticleSelectorRigid(hoomd.context.current.system_definition, False);
cpp_group = _hoomd.ParticleGroup(hoomd.context.current.system_definition, selector);
# notify the user of the created group
hoomd.context.current.device.cpp_msg.notice(2, 'Group "' + name + '" created containing ' + str(cpp_group.getNumMembersGlobal()) + ' particles\n');
# return it in the wrapper class
return group(name, cpp_group);