Source code for elastica.modules.base_system

__doc__ = """
Base System
-----------

Basic coordinating for multiple, smaller systems that have an independently integrable
interface (i.e. works with symplectic or explicit routines `timestepper.py`.)
"""
from typing import Iterable, Callable, AnyStr

from collections.abc import MutableSequence
from itertools import chain

from elastica.rod import RodBase
from elastica.rigidbody import RigidBodyBase
from elastica.modules.memory_block import construct_memory_block_structures


[docs]class BaseSystemCollection(MutableSequence): """ Base System for simulator classes. Every simulation class written by the user must be derived from the BaseSystemCollection class; otherwise the simulation will proceed. Attributes ---------- allowed_sys_types: tuple Tuple of allowed type rod-like objects. Here use a base class for objects, i.e. RodBase. _systems: list List of rod-like objects. """ """ Developer Note ----- Note ---- We can directly subclass a list for the most part, but this is a bad idea, as List is non abstract https://stackoverflow.com/q/3945940 """ def __init__(self): # Collection of functions. Each group is executed as a collection at the different steps. # Each component (Forcing, Connection, etc.) registers the executable (callable) function # in the group that that needs to be executed. These should be initialized before mixin. self._feature_group_synchronize: Iterable[Callable[[float], None]] = [] self._feature_group_constrain_values: Iterable[Callable[[float], None]] = [] self._feature_group_constrain_rates: Iterable[Callable[[float], None]] = [] self._feature_group_callback: Iterable[ Callable[[float, int, AnyStr], None] ] = [] self._feature_group_finalize: Iterable[Callable] = [] # We need to initialize our mixin classes super(BaseSystemCollection, self).__init__() # List of system types/bases that are allowed self.allowed_sys_types = (RodBase, RigidBodyBase) # List of systems to be integrated self._systems = [] # Flag Finalize: Finalizing twice will cause an error, # but the error message is very misleading self._finalize_flag = False def _check_type(self, sys_to_be_added: AnyStr): if not issubclass(sys_to_be_added.__class__, self.allowed_sys_types): raise TypeError( "{0}\n" "is not a system passing validity\n" "checks, that can be added into BaseSystem. If you are sure that\n" "{0}\n" "satisfies all criteria for being a system, please add\n" "it using BaseSystem.extend_allowed_types.\n" "The allowed types are\n" "{1}".format(sys_to_be_added.__class__, self.allowed_sys_types) ) return True def __len__(self): return len(self._systems) def __getitem__(self, idx): return self._systems[idx] def __delitem__(self, idx): del self._systems[idx] def __setitem__(self, idx, system): self._check_type(system) self._systems[idx] = system def insert(self, idx, system): self._check_type(system) self._systems.insert(idx, system) def __str__(self): return str(self._systems) def extend_allowed_types(self, additional_types): self.allowed_sys_types += additional_types def override_allowed_types(self, allowed_types): self.allowed_sys_types = allowed_types def _get_sys_idx_if_valid(self, sys_to_be_added): from numpy import int_ as npint n_systems = len(self._systems) # Total number of systems from mixed-in class if isinstance(sys_to_be_added, (int, npint)): # 1. If they are indices themselves, check range assert ( -n_systems <= sys_to_be_added < n_systems ), "Rod index {} exceeds number of registered rodtems".format( sys_to_be_added ) sys_idx = sys_to_be_added elif self._check_type(sys_to_be_added): # 2. If they are rod objects (most likely), lookup indices # index might have some problems : https://stackoverflow.com/a/176921 try: sys_idx = self._systems.index(sys_to_be_added) except ValueError: raise ValueError( "Rod {} was not found, did you append it to the system?".format( sys_to_be_added ) ) return sys_idx
[docs] def finalize(self): """ This method finalizes the simulator class. When it is called, it is assumed that the user has appended all rod-like objects to the simulator as well as all boundary conditions, callbacks, etc., acting on these rod-like objects. After the finalize method called, the user cannot add new features to the simulator class. """ # This generates more straight-forward error. assert self._finalize_flag is not True, "The finalize cannot be called twice." # construct memory block self._memory_blocks = construct_memory_block_structures(self._systems) # Recurrent call finalize functions for all components. for finalize in self._feature_group_finalize: finalize() # Clear the finalize feature group, just for the safety. self._feature_group_finalize.clear() self._feature_group_finalize = None # Toggle the finalize_flag self._finalize_flag = True
def synchronize(self, time: float): # Collection call _featuer_group_synchronize for feature in self._feature_group_synchronize: feature(time) def constrain_values(self, time: float): # Collection call _feature_group_constrain_values for feature in self._feature_group_constrain_values: feature(time) def constrain_rates(self, time: float): # Collection call _feature_group_constrain_rates for feature in self._feature_group_constrain_rates: feature(time) def apply_callbacks(self, time: float, current_step: int): # Collection call _feature_group_callback for feature in self._feature_group_callback: feature(time, current_step)