Source code for pypdevs.statesavers

# Copyright 2014 Modelling, Simulation and Design Lab (MSDL) at 
# McGill University and the University of Antwerp (http://msdl.cs.mcgill.ca/)
# 
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""
Different methods to save the state, this allows for more modularity than just having a big switch statement in the main code.
Note that these classes are not subclasses of a more generic class, as this allows these classes to save data in a completely
different manner from each other. Furthermore, it avoids (slow) inheritance.
"""
from copy import deepcopy, copy
try:
    import cPickle as pickle
except ImportError:
    import pickle
import marshal

[docs]class DeepCopyState(object): """ Class to save the state using the Python 'deepcopy' library """
[docs] def __init__(self, time_last, time_next, state, activity, my_input, elapsed): """ Constructor :param time_last: time_last to save :param time_next: time_next to save :param state: state to save :param activity: the activity of the computation :param my_input: the state input to save for memorisation :param elapsed: the time elapsed """ self.time_last = time_last self.time_next = time_next self.activity = activity self.state = deepcopy(state) self.my_input = my_input self.elapsed = elapsed
[docs] def loadState(self): """ Load the state from the class, this will make a copy :returns: state - copy of the state that was saved """ return deepcopy(self.state)
[docs]class CopyState(object): """ Class to save the state using the Python 'copy' library """
[docs] def __init__(self, time_last, time_next, state, activity, my_input, elapsed): """ Constructor :param time_last: time_last to save :param time_next: time_next to save :param state: state to save :param activity: the activity of the computation :param my_input: the state input to save for memorisation :param elapsed: the time elapsed """ self.time_last = time_last self.time_next = time_next self.activity = activity self.state = copy(state) self.my_input = my_input self.elapsed = elapsed
[docs] def loadState(self): """ Load the state from the class, this will make a copy :returns: state - copy of the state that was saved """ return copy(self.state)
[docs]class AssignState(object): """ Class to save the state using a simple assignment, is unsafe for most situations... """
[docs] def __init__(self, time_last, time_next, state, activity, my_input, elapsed): """ Constructor :param time_last: time_last to save :param time_next: time_next to save :param state: state to save :param activity: the activity of the computation :param my_input: the state input to save for memorisation :param elapsed: the time elapsed """ self.time_last = time_last self.time_next = time_next self.activity = activity self.state = state self.my_input = my_input self.elapsed = elapsed
[docs] def loadState(self): """ Load the state from the class, this will make a copy :returns: state - copy of the state that was saved """ return self.state
[docs]class PickleZeroState(object): """ Class to save the state using the Python 'pickle' library, with the option to use the pickling protocol 0. """
[docs] def __init__(self, time_last, time_next, state, activity, my_input, elapsed): """ Constructor :param time_last: time_last to save :param time_next: time_next to save :param state: state to save :param activity: the activity of the computation :param my_input: the state input to save for memorisation :param elapsed: the time elapsed """ self.time_last = time_last self.time_next = time_next self.activity = activity self.state = pickle.dumps(state, 0) self.my_input = my_input self.elapsed = elapsed
[docs] def loadState(self): """ Load the state from the class, this will make a copy :returns: state - copy of the state that was saved """ return pickle.loads(self.state)
[docs]class PickleHighestState(object): """ Class to save the state using the Python 'pickle' library, with the option to use the highest available pickling protocol. """
[docs] def __init__(self, time_last, time_next, state, activity, my_input, elapsed): """ Constructor :param time_last: time_last to save :param time_next: time_next to save :param state: state to save :param activity: the activity of the computation :param my_input: the state input to save for memorisation :param elapsed: the time elapsed """ self.time_last = time_last self.time_next = time_next self.activity = activity self.state = pickle.dumps(state, pickle.HIGHEST_PROTOCOL) self.my_input = my_input self.elapsed = elapsed
[docs] def loadState(self): """ Load the state from the class, this will make a copy :returns: state - copy of the state that was saved """ return pickle.loads(self.state)
[docs]class CustomState(object): """ Class to save the state using a manually defined copy() function of the state. If no such method is provided, an error is raised. """
[docs] def __init__(self, time_last, time_next, state, activity, my_input, elapsed): """ Constructor :param time_last: time_last to save :param time_next: time_next to save :param state: state to save :param activity: the activity of the computation :param my_input: the state input to save for memorisation :param elapsed: the time elapsed """ self.time_last = time_last self.time_next = time_next self.activity = activity self.state = state.copy() self.my_input = my_input self.elapsed = elapsed
[docs] def loadState(self): """ Load the state from the class, this will make a copy :returns: state - copy of the state that was saved """ return self.state.copy()
[docs]class MarshalState(object): """ Class to save the state using the Python 'marshal' library. """
[docs] def __init__(self, time_last, time_next, state, activity, my_input, elapsed): """ Constructor :param time_last: time_last to save :param time_next: time_next to save :param state: state to save :param activity: the activity of the computation :param my_input: the state input to save for memorisation :param elapsed: the time elapsed """ self.time_last = time_last self.time_next = time_next self.activity = activity self.state = marshal.dumps(state) self.my_input = my_input self.elapsed = elapsed
[docs] def loadState(self): """ Load the state from the class, this will make a copy :returns: state - copy of the state that was saved """ return marshal.loads(self.state)