fmdtools.sim

The fmdtools.sim package is used to simulate models. It consists of four modules:

fmdtools.sim.propagate, which simulates the user-defined behaviors of a model over set time(s).
fmdtools.sim.scenario, which defines scenario information for simulations.
fmdtools.sim.sample, which provides classes for defining sets of scenarios to simulate.
fmdtools.sim.search, which provides an the ProblemArchitecture and DynamicInterface classes for enabling the search of parameters and/or scenarios.

fmdtools.sim.propagate

The fmdtools.sim.propagate module is used to simulate the behaviors of a fmdtools.define.block.base.Simulable (Model or Block) with and without faults. As shown above, each of the methods (described below) fit a given simulation use-case for resilience assessment–single/multiple scenarios, in nominal/faulty scenarios, and at a single set or multiple sets of parameters.

Description: functions to propagate faults through a user-defined fault model.

Main Methods:

nominal(): Runs the model over time in the nominal scenario.
one_fault(): Runs one fault in the model at a specified time.
sequence(): Runs arbitrary scenario of fault modes at specified times.
single_faults(): Creates and propagates a list of failure scenarios in a model over given model times.
fault_sample(): Injects and propagates faults defined by a FaultSample.
parameter_sample(): Simulates a model over a range of parameters defined by a ParameterSample
nested_sample(): Injects and propagates faults in the model defined by a given SampleApproach over a range of parameters defined by a ParameterSample.

Shared Method Parameters:

sim_kwargs: Simulation keyword arguments.
run_kwargs: Run keyword arguments.
mult_kwargs: Multi-scenario keyword arguments

Private Methods:

list_init_faults(): Creates a list of single-fault scenarios for the graph, given the modes set up in the fault model
prop_one_scen(): Runs a fault scenario in the model over time
save_helper(): Helper function for inline results saving.
unpack _res_list(): Helper function for unpacking results
exec_nom_par(): Helper function for executing nominal scenarios in parallel
exec_nom_helper(): Helper function for executing nominal scenarios
nom_helper(): Helper function for initial run of nominal scenario
scenlist_helper(): Helper function for approach
exec_scen_par(): Helper function for executing the scenario in parallel
exec_scen(): Executes a scenario and generates results and classifications given a model and nominal model history
check_hist_memory(): Checks if the memory will be exhausted given the size of the mdlhist and number of scenarios
check_mdl_memory(): Raises exception if model size is too large.
check_overwrite(): Checks if file can be overwritten
check_end_condition(): Helper function for prop_one_scen to end simulation earlier.
get_result(): Helper function for prop_one_scen to get result at specific timestep.
get_endclass_vars(): Helper function for get_result

fmdtools.sim.propagate.check_end_condition(mdl, use_end_condition, t)

Checks if the end condition of the simulate has been met.

Parameters:

mdl (Simulable) – Model with or without a given end condition and simparam
use_end_condition (bool) – Whether to use the end condition
t (float) – time.

Returns:

end_condition – Whether to end the simulation.

Return type:

bool

fmdtools.sim.propagate.check_hist_memory(mdlhist, nscens, max_mem=2000000000.0): Checks if the memory will be exhausted given the size of the mdlhist and number of scenarios

fmdtools.sim.propagate.check_mdl_memory(mdl, nscens, max_mem=2000000000.0)

fmdtools.sim.propagate.check_overwrite(save_args)

fmdtools.sim.propagate.close_pool(kwargs): Closes pool to avoid memory problems

fmdtools.sim.propagate.exec_nom_helper(mdl, scen, name, **kwargs): Helper function for executing nominal scenarios

fmdtools.sim.propagate.exec_nom_par(arg)

fmdtools.sim.propagate.exec_scen(mdl, scen, save_args={}, indiv_id='', **kwargs)

Executes a scenario and generates results and classifications given a model and nominal model history.

Parameters:

mdl (Simulable) – The model to inject faults in
scen (scenario) – scenario used to define time and faults where the fault is to be injected
save_args (dict) – Save dictionary to use in save_helper defining when/how to save the dictionary
indiv_id (str) – ID str to insert into the file name (if saving individually)
**kwargs (kwargs) – sim_kwargs for prop_one_scen()

fmdtools.sim.propagate.exec_scen_par(args): Helper function for executing the scenario in parallel

fmdtools.sim.propagate.fault_sample(mdl, fs, include_nominal=True, get_phasemap=False, **kwargs)

Injects and propagates faults in the model defined by a FaultSample/SampleApproach.

NOTE: When calling in a script/module using parallel=True, execute using the protection statement

if __name__ == 'main':
    results, mdlhists = fault_sample(mdl, fs)

Otherwise, the method will keep spawning parallel processes. See multiprocessing documentation.

Parameters:

mdl (Simulable) – The model to inject faults in.
fs (FaultSample/SampleApproach) – FaultSample used to define the list of faults and sample time for the model.
include_nominal (bool, optional) – Whether to return nominal hists/results back. Default is True.
get_phasemap (bool, optional) – Whether to regenerate the FaultSample using new phase information.
**kwargs (kwargs) –
Additional keyword arguments, may include:
- sim_kwargskwargs
  Simulation options for prop_one_scen()
- run_kwargskwargs
  Run options for nom_helper() and others
- mult_kwargskwargs
  Multi-scenario options

Returns:

results (Result) – A Result dictionary with results desired from each scenario corresponding to desired_result over the set of scenarios.
mdlhists (History) – A History dictionary with the tracked scenario (including the nominal)

fmdtools.sim.propagate.fault_sample_from(mdl, faultdomains={}, faultsamples={}, get_phasemap=True, scen={}, include_nominal=False, **kwargs)

Create and simulate a fault_sample from the given arguments.

Use to generate and sample from phases in the same simulation.

Parameters:

mdl (Simulable) – Model to simulate
faultdomains (dict) – Dict of arguments to SampleApproach.add_faultdomains
faultsamples (dict) – Dict of arguments to SampleApproach.add_faultsamples FaultSamples to add to othe SampleApproach and their arguments. Has structure:: {‘fs_name’: (*args, **kwargs)} where args and kwargs are arguments/kwargs to SampleApproach.add_faultsamples.
get_phasemap (bool, optional) – Whether to generate the FaultSample from the phasemap. The default is True.
scen (scenario, optional) – Scenario to use as nominal. The default is {}.
include_nominal (bool, optional) – Whether to return nominal hists/results back. Default is False.
**kwargs (kwargs) – kwargs to simulate over

Returns:

res (Result) – A Result dictionary with results desired from each scenario corresponding to desired_result over the set of scenarios.
hist (History) – A History dictionary with the tracked scenario (including the nominal)
app (SampleApproach) – Generated SampleApproach

fmdtools.sim.propagate.gen_sampleapproach(mdl, faultdomains={}, faultsamples={}, get_phasemap=False, nomhist={}): Generate a SampleApproach from faultdomain and faultsample arguments.

fmdtools.sim.propagate.get_endclass_vars(mdl, desired_result, result)

Get variables in the model corresponding to the provided desired_result dictionary.

Appends them to provided result.

Parameters:

mdl (Simulable) – fmdtools Simulation (e.g., Model)
desired_result (dict) – dictionary arguments for desired_result
result (Result) – Result to append results to.

fmdtools.sim.propagate.get_result(scen, mdl, desired_result, nomhist={}, nomresult={}, time=0.0): Get the desired_result specified from the model.

fmdtools.sim.propagate.list_init_faults(mdl, times)

Create list of single-fault scenarios for the given Model mode information.

Parameters:

mdl (Simulable/Function) – Simulable
times – list with list of times in (start_time, end_time)

Returns:

faultlist – A list of SingleFaultScenario

Return type:

list

fmdtools.sim.propagate.mult_kwargs = {'close_pool': True, 'max_mem': 2000000000.0, 'pool': False, 'showprogress': True}

Multi-scenario keyword arguments.

Parameters:

pool (process pool, optional) – Process Pool Object from multiprocessing or pathos packages. e.g. parallelpool = mp.pool(n) for n cores (multiprocessing) or parallelpool = ProcessPool(nodes=n) for n cores (pathos) If False, the set of scenarios is run serially. The default is False
showprogress (bool, optional) – whether to show a progress bar during execution. default is true
max_mem (int) – Max memory (warns the user when memory is above threshold)

fmdtools.sim.propagate.nested_sample(mdl, ps, get_phasemap=False, faultdomains={}, faultsamples={}, include_nominal=True, **kwargs)

Simulate a set of fault scenarios within a ParameterSample.

NOTE: When calling in a script/module using parallel=True, execute using the protection statement

if __name__ == "main":
    results, mdlhists = nested_sample(mdl, ps)

Otherwise, the method will keep spawning parallel processes. See multiprocessing documentation.

Parameters:

mdl (Simulable) – Model Object to use in the simulation.
ps (ParameterSample) – Parameter Scenario defining the parameters the model will be run over
get_phasemap (Bool/List/Dict, optional) – Whether to use nominal simulation phasemap to set up the SampleApproach.
faultdomains (dict) – Dict of arguments to SampleApproach.add_faultdomains
faultsamples (dict) – Dict of arguments to SampleApproach.add_faultsamples FaultSamples to add to othe SampleApproach and their arguments. Has structure:: {‘fs_name’: (*args, **kwargs)} where args and kwargs are arguments/kwargs to SampleApproach.add_faultsamples.
include_nominal (bool, optional) – Whether to return nominal hists/results back. Default is False.
**kwargs (kwargs) –
Additional keyword arguments, may include:
- sim_kwargskwargs
  Simulation options for prop_one_scen().
- run_kwargskwargs
  Run options for nom_helper() and others.
- mult_kwargskwargs
  Multi-scenario options
- app_argsmdl_kwargs
  Keyword arguments for the SampleApproach. See sim.sample.SampleApproach documentation.

Returns:

nested_results (Result) – A nested Result dictionary with the desired results of each scenario.
nested_mdlhists (History) – A nested History dictionary with the history of all model states for each scenario
apps (dict) – A dictionary of the SampleApproaches generated corresponding to each nominal scenario with structure {‘nomscen1’: app1}

fmdtools.sim.propagate.nom_helper(mdl, ctimes, protect=True, save_args={}, mdl_kwargs={}, scen={}, warn_faults=True, **kwargs)

Run initial run of nominal scenario.

Parameters:

mdl (Simulable (object or class)) – Model of the system
ctimes (float/list) – Times to copy the nominal model from
protect (bool) –
Whether or not to protect the model object via copying. Options:
- True (default): re-instances the model so that multiple simulations can
be run successively without causing problems - False : Thus, the model object that is returned can be modified and analyzed if needed
save_args (dict (optional)) –
Dictionary specifying if/how to save results. Default is {}, which doesn’t save anything. Has structure
```
{'mdlhists':mdlhistargs, 'endclass':endclassargs, 'indiv':indiv}
```
mdl_kwargs (dict, optional) –
Model arameter dictionary. Has structure
```
{"p": Parameter, "sp":SimParam, "track":track}
```
scen (scenario, optional) – Scenario to use. The default is {}.
warn_faults (bool) – choose whether to display a warning message if faults are identified during nominal runs. Default is True.
**kwargs (kwargs) – sim_kwargs simulation options for prop_one_scen()

Returns:

result (Result) – results dict from nominal sim
nommdlhist (History) – result history from nominal sim
nomscen (dict) – nominal scenario dict
mdls (list) – Models from copy time(s) ctimes
t_end_nom (float) – Nominal simulation end time

fmdtools.sim.propagate.nominal(mdl, **kwargs)

Run the model over time in the nominal scenario.

Parameters:

mdl (Simulable) – Model of the system
**kwargs (kwargs) –
Additional keyword arguments, may include:
- sim_kwargskwargs
  Simulation options for prop_one_scen()
- run_kwargskwargs
  Run options for nom_helper() and others

Returns:

result (Result) –

dict of result corresponding to desired_result, e.g.

Result({'endclass': endclasses,
        'endfaults': endfaults,
        'varname': var,
        t: {'endclass': endclasses...} ...})

nomhist (History) – A History dict with a history of modelstates

fmdtools.sim.propagate.one_fault(mdl, *fxnfault, time=0, **kwargs)

Run one fault in the model at a specified time.

Parameters:

mdl (Simulable) – The model to inject the fault in.
*fxnfault (str) – Has options: - ‘fxnname’, ‘faultmode’ when a Model is provided, or - ‘faultmode’ when a Block/Function is provided
time (float, optional) – Time to inject fault. Must be in the range of model times (i.e. in range(0, end, mdl.sp.dt)). The default is 0.
**kwargs (kwargs) –
Additional keyword arguments, may include:
- sim_kwargskwargs
  Simulation options for prop_one_scen()
- run_kwargskwargs
  Run options for nom_helper() and others

Returns:

result (Result) –

Result dict of result corresponding to desired_result, with structure,:
```
Result({'nominal': nomresult, 'faulty': faultyresult})
```
mdlhists (History) – A dictionary of the states of the model of each fault scenario over time with structure: {‘nominal’: nomhist, ‘faulty’: faulthist}

fmdtools.sim.propagate.pack_mult_kwargs(**kwargs): Create subset of mult kwargs.

fmdtools.sim.propagate.pack_run_kwargs(**kwargs): Creates subset of run kwargs for nom_helper() and run_kwarg

fmdtools.sim.propagate.pack_sim_kwargs(**kwargs): Creates sim_kwargs for prop_one_scen()

fmdtools.sim.propagate.parameter_sample(mdl, ps, **kwargs)

Simulate a set of nominal scenarios through a model.

Useful for exploring/understanding the sets of parameters where the system will run nominally and/or fail.

Parameters:

mdl (Simulable) – Model to simulate
ps (ParameterSample) – Parameter Sample defining the nominal scenarios to run the system over.
**kwargs (kwargs) –
Additional keyword arguments, may include:
- sim_kwargskwargs
  Simulation options for prop_one_scen()
- run_kwargskwargs
  Run options for nom_helper() and others
- mult_kwargskwargs
  Multi-scenario options

Returns:

nomresults (Result) – Result dict of result corresponding to desired result {‘scenname’: result}
nomhists (History) – History of model histories, with structure {‘scenname’: mdlhist}

fmdtools.sim.propagate.process_nominal(mdlhists, nomhist, results, nomresult, t_end_nom, **kwargs): Add/save nominal hists/result to overall hist/result.

fmdtools.sim.propagate.prop_one_scen(mdl, scen, ctimes=[], nomhist={}, nomresult={}, **kwargs)

Runs a fault scenario in the model over time

Parameters:

mdl (Simulable) – The model to inject faults in.
scen (Scenario) – The Scenario to run.
ctimes (list, optional) – List of times to copy the model (for use in staged execution). The default is [].
nomhist (dict, optional) – Model history dictionary from previous runs, for use in creating the new mdlhist. The default is {}.
nomresult (dict, optional) – Nominal result dictionary (to compare with current if desired)
**kwargs (kwargs) – simulation options, see sim_kwargs

Returns:

result (Result) – dict of result corresponding to desired_result.
mdlhist (dict) – A dictionary with a history of modelstates.
c_mdl (dict) – A dictionary of models at each time given in ctimes with structure {time:model}
t_end (float) – Last sim time

fmdtools.sim.propagate.run_kwargs = {'mdl_kwargs': {}, 'protect': True, 'save_args': {}}

Run keyword arguments.

Parameters:

protect (bool) –
Whether or not to protect the model object via copying. Options:
- True (default): re-instances the model so that multiple simulations can be run successively without causing problems
- False : Thus, the model object that is returned can be modified and analyzed if needed
save_args (dict (optional)) –
Dictionary specifying if/how to save results. Default is {}, which doesn’t save anything. Has structure
```
{'mdlhists':mdlhistargs, 'endclass':endclassargs, 'indiv':indiv}
```
where mdlhistargs and endclassargs are dictionaries of save arguments, e.g.,:
```
{'filename':'filename.npz', 'filetype':'npz', 'overwrite':True}
```
and indiv is an (optional) bool specifying whether to save results individually (in a folder) or as a monolythic file.
mdl_kwargs (dict (optional)) –
Parameter dictionary to be instantiated in the model prior to simulation. Has structure
```
{"p": Parameter, "sp":SimParam, "track":track}
```
Parameter dictionaries do not need to be complete (if incomplete).

fmdtools.sim.propagate.save_helper(save_args, endclass, mdlhist, indiv_id='', result_id='')

Helper function for inline results saving.

Parameters:

save_args (dict) –
Dict with structure
```
{'mdlhists': mdlhistargs,
 'endclass': endclassargs,
 'indiv': individual_saving}
```
where mdlhistargs and endclassargs are dictionaries of arguments to Result.save (i.e., {‘filename’:’filename.pkl’, ‘filetype’:’pickle’, ‘overwrite’:True}) and individual_saving is a bool (True/False)
endclass (dict) – dict of end-state classifications (from simulation)
mdlhist (dict) – dict of model histories (from simulation)

fmdtools.sim.propagate.scenlist_helper(mdl, scenlist, c_mdl, **kwargs)

fmdtools.sim.propagate.sequence(mdl, seq={}, faultseq={}, disturbances={}, scen={}, rate=nan, include_nominal=True, **kwargs)

Run a sequence of faults and disturbances in the model at given times.

Parameters:

mdl (Simulable) – The model to inject the fault in.
seq (dict) – Scenario dict defining the scenario {time:{faults:faults, disturbances:disturbances}}
faultseq (dict) – Dict of times and modes defining the fault scenario {time:{fxns: [modes]},}
disturbances (dict) –
Dict of times and states defining the disturbances in the scenario:
```
{time: {path.to.state: stateval}}
```
scen (Scenario, optional) – Scenario dictionary, if already constructed (for external calls)
rate (float, optional) – Input rate for the sequence (must be calculated elsewhere)
include_nominal (bool, optional) – Whether to return nominal hists/results back. Default is True.
**kwargs (kwargs) –
Additional keyword arguments, may include:
- sim_kwargskwargs
  Simulation options for prop_one_scen()
- run_kwargskwargs
  Run options for nom_helper() and others

Returns:

result (Result) –

Result dict of result corresponding to desired_result, with structure,:
```
Result({'nominal': nomresult, 'faulty': faultyresult})
```
mdlhists (dict) – A dictionary of the states of the model of each fault scenario over time with structure: {‘nominal’: nomhist, ‘faulty’: faulthist}

fmdtools.sim.propagate.sim_kwargs = {'cut_hist': True, 'desired_result': 'endclass', 'run_stochastic': False, 'staged': False, 'use_end_condition': True, 'warn_faults': True}

Simulation keyword arguments.

Parameters:

desired_result (dict/str/list) –
Desired quantities to return in the first argument. Options are:
- ’endclass’: a dict returned by find_classification (default)
- ’endfaults’: a dict of returned fault modes and their propagation, e.g.,
```
{'endfaults':faultdict, 'faultprops':faultpropdict}
```
- ’graph’/’flowgraph’/etc: a networkx graph of the model with fault modes superimposed
- ’fxnname.varname’: variable values to get
- a list of the above arguments (for multiple at the end)
- a dict of lists (for multiple over time), e.g.,
```
{time:[varnames,... 'endclass']}
```
The default is ‘all’.
run_stochastic (bool) – Whether to run stochastic behaviors or use default values. Default is False. Can set as ‘track_pdf’ to calculate/track the probability densities of random states over time.
staged (bool, optional) – Whether to inject the faults in a copy of the nominal model at the fault time (True) or instantiate a new model for the fault (False). Setting to True roughly halves execution time. The default is False.
warn_faults (bool) – Whether to produce a warning when faults occur in a nominal sim.

fmdtools.sim.propagate.single_faults(mdl, times=[0.0], include_nominal=True, **kwargs)

Create and propagates a list of failure scenarios in a model.

NOTE: When calling in a script/module using parallel=True, execute using the protection statement

if __name__ == 'main':
    results, mdlhists = single_faults(mdl)

Otherwise, the method will keep spawning parallel processes. See multiprocessing documentation.

Parameters:

mdl (Simulable) – The model to inject faults in
times (list) – List of times to inject the single faults in. Default is [1.0]
include_nominal (bool, optional) – Whether to return nominal hists/results back. Default is True.
**kwargs (kwargs) –
Additional keyword arguments, may include:
- sim_kwargskwargs
  Simulation options for prop_one_scen()
- run_kwargskwargs
  Run options for nom_helper() and others
- mult_kwargskwargs
  Multi-scenario options

Returns:

results (Result) – Result dict of result corresponding to desired_result {scenname:result}
mdlhists (History) – History dict with the history of all tracked model states for each scenario (including the nominal)

fmdtools.sim.propagate.unpack_mult_kwargs(kwargs): Unpack the mult kwarg parameters for the parameter_sample().

fmdtools.sim.propagate.unpack_res_list(scenlist, res_list)

fmdtools.sim.propagate.unpack_sim_kwargs(**kwargs): Unpacks sim_kwargs parameters for prop_one_scen()

fmdtools.sim.scenario

Description: Classes for defining scenarios to simulate.

Classes:

Injection: Defines faults and disturbances to inject at a specific time.
Scenario: Defines a generic scenario to simulation.
SingleFaultScenario: Defines the scenario of a single fault injected in a function.
JointFaultScenario: Defines the scenario of multiple faults injected in a function at the same time.
NominalScenario: Defines the scenario of a model having given parameters at the outset.
ParamScenario: Defines the scenario of a model having parameters from a given paramfunc.
Sequence: Creates an overall sequence of Injections from a given sequence of faults and disturbances.

class fmdtools.sim.scenario.BaseScenObj

Bases: dataobject

Base class for Scenarios and injections.

copy_with(**kwargs)

Copy the Scen with the given kwargs.

Parameters:: **kwargs (kwargs) – Fields to change in the copy
Returns:: copy – Copy of self with optional kwargs.
Return type:: BaseScenObj

get(entry, fallback)

Get entry if present, otherwise return fallback.

Parameters:

entry (str) – Name of field to get.
fallback (val) – Fallback value

Returns:

val_to_get – Value of entry (or fallback, if no entry)

Return type:

val

class fmdtools.sim.scenario.BaseScenario

Bases: BaseScenObj

Base class for scenarios.

…

Parameters:

sequence (Sequence) – Sequence of faults and distrubances over time defined by Sequence
times (tuple) – Times faunts/distrubances will occur.
Variables (Class) –
--------------- –
prob (float) – Scenario probability
rate (float) – Scenario rate.
name (str) – Scenario name.
time (float) – Start of scenario.

name = 'nominal'

prob = 1.0

rate = 1.0

sequence: Sequence

start_time(): Get the first time in the scenario.

time = 0.0

times: tuple

class fmdtools.sim.scenario.Injection

Bases: BaseScenObj

Defines a single fault/disturbance injection.

…

faultsdict: Faults to inject with structure {‘fxnname’: [faults]}
disturbancesdict: Disturbances to inject with structure {‘path.to.state’: statevalue}

disturbances: dict

faults: dict

update(inj)

Update the injection with the given faults/disturbances.

Parameters:: inj (dict) – Dict with structure {‘faults’: faults, ‘disturbances’: disturbances}

class fmdtools.sim.scenario.JointFaultScenario

Bases: BaseScenario

Class defining a joint fault occuring. Extends BaseScenario.

Parameters:

joint_faults (int) – Joint Faults in the scenario
functions (tuple) – Functions where the faults are to occur
modes (tuple) – Names of the fault modes

classmethod from_faults(faulttups, time, mdl=None, phasemap=None, weight=1.0, baserate='ind', p_cond=1.0, starttime=None): Generate JointFaultScenario given fault names, time.

functions: tuple

joint_faults: int

modes: tuple

name: str

phase: tuple

rate: float

sequence: Sequence

time: float

times: tuple

class fmdtools.sim.scenario.ParameterScenario

Bases: BaseScenario

Class defining a nominal (non-fault-injection) Scenario.

Parameters:

p (dict) – non-default Parameter fields
r (dict) – non-default Rand fields
sp (dict) – non-default SimParam fields
prob (float) – probability
inputparams (dict) – inputs to parameter generator
rangeid (str) – name of containing range
name (str) – scenario name

get_param(param, default='NA')

Get a parameter from the scenario.

Parameters:

param (str) – Name of parameter (e.g., “p.size”)
default (val, optional) – Default value for field (if not present). The default is “NA”.

Returns:

pval – Value of the parameter.

Return type:

val

get_params(*params, default='NA')

Get a list of parameters for the scenarios.

Parameters:

*params (str) – Name of parameters
default (val, optional) – Default value for parameters (if not present). The default is “NA”.

Returns:

params – List of parameters.

Return type:

list

inputparams: dict

name: str

p: dict

prob: float

r: dict

rangeid: str

sequence: Sequence

sp: dict

start_time(): Return the start time for a parameter scenario–0.0.

times: tuple

class fmdtools.sim.scenario.Scenario

Bases: BaseScenario

Class defining generic scenarios. Extends BaseScenario.

name: str

rate: float

sequence: Sequence

time: float

times: tuple

class fmdtools.sim.scenario.Sequence(faultseq={}, disturbances={})

Bases: UserDict

Defines a dict with a sequence of faults and disturbances.

Examples

>>> s = Sequence(faultseq={1: {'fxnname':['mode1']}},
...              disturbances={2: {'state.name': 1.0}})
>>> s[1]
Injection(faults={'fxnname': ['mode1']}, disturbances={})
>>> s[2]
Injection(faults={}, disturbances={'state.name': 1.0})

>>> Sequence({1: {'fxnname': ['mode1']}}, {1: {'state.name': 1.0}})
{1: Injection(faults={'fxnname': ['mode1']}, disturbances={'state.name': 1.0})}

classmethod from_fault(faulttup, time): Generate sequence from single fault mode faulttup (fxn, mode).

update_sequence(new_sequence)

Update the sequence given a different sequence.

Parameters:: new_sequence (Sequence) – Sequence to update from

Examples

>>> s = Sequence(faultseq={1: {'fxnname':['mode1']}},
...              disturbances={2: {'state.name': 1.0}})
>>> s2 = Sequence({1: {'fxnname': ['mode2']}}, {1: {'state.name': 1.0}})
>>> s.update_sequence(s2)
>>> s
{1: Injection(faults={'fxnname': ['mode2']}, disturbances={'state.name': 1.0}), 2: Injection(faults={}, disturbances={'state.name': 1.0})}

class fmdtools.sim.scenario.SingleFaultScenario

Bases: BaseScenario

Class defining a single fault occuring. Extends BaseScenario.

Parameters:

function (str) – Function where the fault occurs
fault (str) – Name of the fault

fault: str

classmethod from_fault(faulttup, time, mdl=None, weight=1.0, phasemap=None, starttime=None): Generate the fault scenario for faulttup at time.

function: str

name: str

phase: str

rate: float

sequence: Sequence

time: float

times: tuple

fmdtools.sim.scenario.create_scenname(faulttup, time): Create a scenario name for a given fault scenario.

fmdtools.sim.sample

Module for Fault Sampling. Takes the place of approach classes.

Has classes:

ParameterDomain: Defines domain for sampling from Parameters.
FaultDomain: Defines domain for sampling from Faults.
FaultSample: Defines a sample of fault scenarios.
SampleApproach: Defines a set of fault scenario samples.
ParameterSample: Defines a sample of a set of parameters.
ParameterResultSample: Defines a sample from Result values.
ParameterHistSample: Defines a sample from History values.

class fmdtools.sim.sample.BaseSample

Bases: object

Overarching sample class (for FaultSample and SampleApproach).

Subclasses should have methods:

scenarios() for getting all scenarios from the sample
times() for getting all times from the sample

get_factor_metrics(res, metrics=['cost'], factors=['time'], default_stat='expected', stats={}, ci_metrics=[], ci_kwargs={})

Make a dict of the statistic for given metrics over given factors.

Parameters:

res (Result) – Result with the given metrics over a number of scenarios.
metrics (list) – metrics in res to tabulate over time. Default is [‘cost’].
factors (list) – Factors (Scenario properties e.g., ‘name’, ‘time’, ‘var’) in samp to take the statistic over. Default is [‘time’]
default_stat (str) – statistic to take for given metrics my default. (e.g., ‘average’, ‘percent’… see Result methods). Default is ‘expected’.
stats (dict) – Non-default statistics to take for each individual metric. e.g. {‘cost’: ‘average’}. Default is {}
ci_metrics (list) – Metrics to calculate a confidence interval for (using bootstrap_ci). Default is [].
ci_kwargs (dict) – kwargs to bootstrap_ci

Returns:

met_table – pandas dataframe with the statistic of the metric over the corresponding set of scenarios for the given factor level.

Return type:

dict

get_groups_scens(groupnames, groups)

Get scenarios related to the given groups.

Parameters:

groupnames (list) – List of scenario properties to group (e.g., ‘function’’, ‘fault’)
groups (list) – Groups to get e.g, [ (‘fxnname1’, ‘fault1’)]

Returns:

scen_groups – dict of scenarios for each group with structure {(field1_val, field2_val) : [scenarios]}

Return type:

dict

get_scen_groups(*groupnames)

Get all groups of scenarios grouped by *groupnames.

Parameters:: *groupnames (str) – Fields of the underlying scenarios in self.scenarios()
Returns:: scen_groups – Dict of scenarios
Return type:: dict

get_scens(**kwargs)

Get scenarios with the values corresponding to **kwargs.

Parameters:: **kwargs (kwargs) – key-value pairs for the Scenario (e.g., fault=’faultname’)
Returns:: scens – Dict of scenarios with the given properties.
Return type:: dict

group_scens(*groupnames)

Get the groups of scenario parameters corresponding to *groupnames.

Parameters:: *groupnames (str) – Fields of the scenarios to group. e.g., ‘function’ or ‘fault’
Returns:: groups – List of tuples corresponding to the groups
Return type:: list

named_scenarios(): Get dict of scenarios by name.

num_scenarios(): Get the number of scenarios in the sample.

scen_names(): Get list of scen names.

class fmdtools.sim.sample.ExNestedParam(*args, strict_immutability=True, check_type=True, check_pickle=True, set_type=True, check_lim=True, **kwargs)

Bases: Parameter

Example nested parameter for testing ParamDomain.

ex_param: ExampleParameter

k: float

class fmdtools.sim.sample.FaultDomain(mdl)

Bases: object

Defines the faults which will be sampled from in an approach.

…

fxns

Dict of fxns in the given Simulable (to simulate)

Type:: dict

faults

Dict of faults to inject in the simulable

Type:: dict

add_all()

Add all faults in the Simulable to the FaultDomain.

Examples

>>> from examples.multirotor.drone_mdl_rural import Drone
>>> fd = FaultDomain(Drone().fxns['ctl_dof'])
>>> fd.add_all()
>>> fd
FaultDomain with faults:
 -('ctl_dof', 'noctl')
 -('ctl_dof', 'degctl')

add_all_fxn_modes(*fxnnames)

Add all modes in the given simname.

Parameters:: *fxnnames (str) – Names of the functions (e.g., “affect_dof”, “move_water”).

Examples

>>> from examples.multirotor.drone_mdl_rural import Drone
>>> fd = FaultDomain(Drone())
>>> fd.add_all_fxn_modes("hold_payload")
>>> fd
FaultDomain with faults:
 -('hold_payload', 'break')
 -('hold_payload', 'deform')

add_all_fxnclass_modes(*fxnclasses)

Add all modes corresponding to the given fxnclasses.

Parameters:: *fxnclasses (str) – Name of the fxnclass (e.g., “AffectDOF”, “MoveWater”)

Examples

>>> from examples.eps.eps import EPS
>>> fd1 = FaultDomain(EPS())
>>> fd1.add_all_fxnclass_modes("ExportHE")
>>> fd1
FaultDomain with faults:
 -('export_he', 'hot_sink')
 -('export_he', 'ineffective_sink')
 -('export_waste_h1', 'hot_sink')
 -('export_waste_h1', 'ineffective_sink')
 -('export_waste_ho', 'hot_sink')
 -('export_waste_ho', 'ineffective_sink')
 -('export_waste_hm', 'hot_sink')
 -('export_waste_hm', 'ineffective_sink')

add_all_modes(*modenames, exact=True)

Add all modes with the given modenames to the FaultDomain.

Parameters:

*modenames (str) – Names of the modes
exact (bool, optional) – Whether the mode name must be an exact match. The default is True.

add_fault(fxnname, faultmode)

Add a fault to the FaultDomain.

Parameters:

fxnname (str) – Name of the simulable to inject in
faultmode (str) – Name of the faultmode to inject.

add_faults(*faults)

Add multiple faults to the FaultDomain.

Parameters:: *faults (tuple) – Faults (simname, faultmode) to inject

Examples

>>> from examples.multirotor.drone_mdl_rural import Drone
>>> fd= FaultDomain(Drone())
>>> fd.add_faults(('ctl_dof', 'noctl'), ('affect_dof', 'rr_ctldn'))
>>> fd
FaultDomain with faults:
 -('ctl_dof', 'noctl')
 -('affect_dof', 'rr_ctldn')

add_singlecomp_modes(*fxns)

Add all single-component modes in functions.

Parameters:: *fxns (str) – Names of the functions containing the components.

Examples

>>> from examples.multirotor.drone_mdl_rural import Drone
>>> fd = FaultDomain(Drone())
>>> fd.add_singlecomp_modes("affect_dof")
>>> fd
FaultDomain with faults:
 -('affect_dof', 'lf_short')
 -('affect_dof', 'lf_openc')
 -('affect_dof', 'lf_ctlup')
 -('affect_dof', 'lf_ctldn')
 -('affect_dof', 'lf_ctlbreak')
 -('affect_dof', 'lf_mechbreak')
 -('affect_dof', 'lf_mechfriction')
 -('affect_dof', 'lf_propwarp')
 -('affect_dof', 'lf_propstuck')
 -('affect_dof', 'lf_propbreak')

class fmdtools.sim.sample.FaultSample(faultdomain, phasemap={}, def_mdl_phasemap=True)

Bases: BaseSample

Defines a sample of a given faultdomain.

…

Parameters:

faultdomain (FaultDomain) – Domain of faults to sample from
phasemap (PhaseMap, (optional)) – Phases of operation to sample over.

_scenarios

List of scenarios to sample.

Type:: list

_times

Set of times where the scenarios will occur

Type:: set

add_fault_phases(*phases_to_sample, method='even', args=(1,), phase_methods={}, phase_args={}, n_joint=1, **joint_kwargs)

Sample scenarios in the given phases using a set sampling method.

Parameters:

*phases_to_sample (str) – Names of phases to sample. If no
method (str, optional) – ‘even’, ‘quad’, ‘all’, which selects whether to use sample_times_even or sample_times_quad, or gets all times, respectively. The default is ‘even’.
args (tuple, optional) – Arguments to the sampling method. The default is (1,).
phase_methods (dict, optional) – Method (‘even’ or ‘quad’) to use of individual phases (if not default). The default is {}.
phase_args (dict, optional) – Method args to use for individual phases (if not default). The default is {}.
n_joint (int) – Number of joint fault modes to include in sample.
**joint_kwargs (kwargs) – baserate and p_cond arguments to add_joint_fault_scenario.

Examples

>>> from examples.multirotor.drone_mdl_rural import Drone
>>> mdl = Drone()
>>> fd = FaultDomain(mdl)
>>> fd.add_fault("affect_dof", "rf_propwarp")
>>> fs = FaultSample(fd, phasemap=PhaseMap({"on": [0, 2], "off": [3, 5]}))
>>> fs.add_fault_phases("off")
>>> fs
FaultSample of scenarios:
 - affect_dof_rf_propwarp_t4p0

add_fault_times(times, weights=[], n_joint=1, **joint_kwargs)

Add all single-fault scenarios to the list of scenarios at the given times.

Parameters:

times (list) – List of times.
weights (list, optional) – Weight factors corresponding to the times The default is [].
n_joint (int) – Number of joint fault modes.
**joint_kwargs (kwargs) – baserate and p_cond arguments to add_joint_fault_scenario.

Examples

>>> from examples.multirotor.drone_mdl_rural import Drone
>>> mdl = Drone()
>>> fd = FaultDomain(mdl)
>>> fd.add_fault("affect_dof", "rf_propwarp")
>>> fs = FaultSample(fd, phasemap=PhaseMap({"on": [0, 2], "off": [3, 5]}))
>>> fs.add_fault_times([1,2,3])
>>> fs
FaultSample of scenarios:
 - affect_dof_rf_propwarp_t1
 - affect_dof_rf_propwarp_t2
 - affect_dof_rf_propwarp_t3
 >>> fd.add_fault("affect_dof", "lf_propwarp")
 >>> fd.add_fault("affect_dof", "rr_propwarp")
 >>> fs = FaultSample(fd)
 >>> fs.add_fault_times([5], n_joint=2)
 >>> fs
 FaultSample of scenarios:
  - affect_dof_rf_propwarp__affect_dof_lf_propwarp_t5
  - affect_dof_rf_propwarp__affect_dof_rr_propwarp_t5
  - affect_dof_lf_propwarp__affect_dof_rr_propwarp_t5
 >>> fs = FaultSample(fd)
 >>> fs.add_fault_times([5], n_joint=3)
 >>> fs
 FaultSample of scenarios:
  - affect_dof_rf_propwarp__affect_dof_lf_propwarp__affect_dof_rr_propwarp_t5

add_joint_fault_scenario(faulttups, time, weight=1.0, baserate='ind', p_cond=1.0)

Add a single fault scenario to the list of scenarios.

Parameters:

faulttups (tuple) – Faults to add ((‘blockname’, ‘faultname’), (‘blockname2’, ‘faultname2’)).
time (float) – Time of the fault scenario.
weight (float, optional) – Weighting factor for the scenario rate. The default is 1.0.
baserate (str/tuple) – Fault (fxn, mode) to get base rate for the scenario from (for joint faults). Default is ‘ind’ which calculates the rate as independent (rate1*rate2*…). Can also be ‘max’, which uses the max fault likelihood.
p_cond (float) – Conditional fault probability for joint fault modes. Used if not using independent base rate assumptions to calculate. Default is 1.0.

Examples

>>> from examples.multirotor.drone_mdl_rural import Drone
>>> fd = FaultDomain(Drone())
>>> fd.add_fault("affect_dof", "rf_propwarp")
>>> fd.add_fault("affect_dof", "lf_propwarp")
>>> fs = FaultSample(fd, phasemap=PhaseMap({"on": [0, 2], "off": [3, 5]}))
>>> fs.add_joint_fault_scenario((("affect_dof", "rf_propwarp"),("affect_dof", "lf_propwarp")), 5)
>>> fs
FaultSample of scenarios:
 - affect_dof_rf_propwarp__affect_dof_lf_propwarp_t5
>>> fs.scenarios()[0].sequence[5].faults
{'affect_dof': ['rf_propwarp', 'lf_propwarp']}
>>> fs.add_single_fault_scenario(("affect_dof", "rf_propwarp"), 5)
>>> fs.add_single_fault_scenario(("affect_dof", "lf_propwarp"), 5)
>>> fs.scenarios()[0].rate == fs.scenarios()[1].rate*fs.scenarios()[2].rate
True

add_single_fault_scenario(faulttup, time, weight=1.0)

Add a single fault scenario to the list of scenarios.

Parameters:

faulttup (tuple) – Fault to add (‘blockname’, ‘faultname’).
time (float) – Time of the fault scenario.
weight (float, optional) – Weighting factor for the scenario rate. The default is 1.0.

Examples

>>> from examples.multirotor.drone_mdl_rural import Drone
>>> mdl = Drone()
>>> fd = FaultDomain(mdl)
>>> fd.add_fault("affect_dof", "rf_propwarp")
>>> fs = FaultSample(fd, phasemap=PhaseMap({"on": [0, 2], "off": [3, 5]}))
>>> fs.add_single_fault_scenario(("affect_dof", "rf_propwarp"), 5)
>>> fs
FaultSample of scenarios:
 - affect_dof_rf_propwarp_t5

prune_scenarios(scen_var='rate', comparator=<ufunc 'greater'>, value=0.0)

Prune scenarios from the FaultSample.

Parameters:

scen_var (str, optional) – Variable to prune. The default is ‘rate’.
comparator (method, optional) – Numpy method. The default is np.greater_equal.
value (float, optional) – Value to compare against. The default is 0.0.

scenarios(): Get all sampled scenarios.

times(): Get all sampled times.

class fmdtools.sim.sample.JointFaultSample(*faultdomains, phasemaps=[], def_mdl_phasemap=True)

Bases: FaultSample

FaultSample for faults in multiple faultdomains and phasemaps.

class fmdtools.sim.sample.ParameterDomain(parameter_init)

Bases: object

Defines a domain to sample from a Parameter.

…

parameter_init

Method which may be used to initialize a parameter. If a method is provided, it may only take kwargs as input (which will map to ParameterDomain variables).

Type:: Parameter/method

variables

Variables (inputs to parameter_init) and their range/set constraints.

Type:: dict

constants

Variables (inputs to parameter_init) with set parameter values.

Type:: dict

Examples

Given the parameter:

>>> class ExampleParameter(Parameter):
...    x: float = 1.0
...    y: float = 10.0
...    z: float = 0.0
...    x_lim = (0, 10)
...    y_set = (1.0, 2.0, 3.0, 4.0)

We can then define the following domain, which by default gets set constraints:

>>> expd = ParameterDomain(ExampleParameter)
>>> expd.add_variables("y", "x")
>>> expd.add_constants(z=20)
>>> expd
ParameterDomain with:
 - variables: {'y': {1.0, 2.0, 3.0, 4.0}, 'x': (0, 10)}
 - constants: {'z': 20}
 - parameter_initializer: ExampleParameter

This ParameterDomain then becomes a callable with the given variables:

>>> expd(1, 2)
ExampleParameter(x=2.0, y=1.0, z=20.0)

And we can separately check the set contraints for the variables:

>>> expd.get_set_constraints(1, 2)
(False, False)
>>> expd.get_set_constraints(0, 20)
(True, True)

This can also work with nested parameters:

>>> class ExNestedParam(Parameter):
...    ex_param: ExampleParameter = ExampleParameter()
...    k: float = 20.0

>>> expd1 = ParameterDomain(ExNestedParam)
>>> expd1.add_variables("ex_param.x", "ex_param.y", "k")
>>> expd1(1,2, 3)
ExNestedParam(ex_param=ExampleParameter(x=1.0, y=2.0, z=0.0), k=3.0)

add_constant(constant, value)

Add a value to be set to a constant value in the ParameterDomain.

Parameters:

constant (str) – Name of the parameter_init field to set to the constant value.
value (value) – Value to set the constant to.

add_constants(**constants)

Add a number of constant values to the ParameterDomain to be set as constant.

Parameters:: **constants (kwargs) – args to set as constant and their values.

add_variable(variable, var_set=(), var_lim=(), var_map=<function pass_var>)

Add a variable to the ParameterDomain.

Parameters:

variable (str) – Name of the variable in parameter_init.
var_set (tuple, optional) – Discrete set constraints for the variable. The default is ().
var_lim (tuple, optional) – Variable limits. The default is ().
var_map (function, optional) – Preprocessing variable mapping, mapping the input to the parameter domain to the actual variable value. May be used to e.g., encode different discrete options listed as strings (‘arch1’, ‘arch2’) as integers (1, 2). The default is pass_var, which passes the input variable.

add_variables(*variables, sets={}, lims={}, var_map=<function pass_var>)

Add a list of variables to the ParameterDomain.

Parameters:

*variables (str) – Names of the variables in parameter_init
sets (dict, optional) – Set constraints for the variables. The default is {}.
lims (dict, optional) – Variable limits. The default is {}.
var_map (function, optional) – Preprocessing variable mapping, mapping the input to the parameter domain to the actual variable value. May be used to e.g., encode different discrete options listed as strings (‘arch1’, ‘arch2’) as integers (1, 2). The default is pass_var, which passes the input variable.

get_map_vars(*x): Get the mapped variables for x.

get_param_kwargs(*x): Get kwargs for the parameter at the given value of x.

get_set_constraints(*x)

Get the set constraints at a value of the variables x.

Parameters:: *x (values) – Values of the variables.
Returns:: set_constraints – Set constraint values (True or False) accross the variables. If False, the constraint is met. If True, the constraint is violated.
Return type:: tuple

get_var_iters(resolution=1.0, resolutions={})

Get iterables for each variable (provided given resolution).

Parameters:

resolution (float, optional) – Default resolution for the ranges. The default is 1.
resolutions (dict, optional) – Dict of resolutions for each variable e.g. {‘var1’: 0.1}. The default is {}.

Returns:

var_iters – Dict or iterables for each variable.

Return type:

dict

Examples

>>> expd.get_var_iters()
{'y': {1.0, 2.0, 3.0, 4.0}, 'x': array([ 0.,  1.,  2.,  3.,  4.,  5.,  6.,  7.,  8.,  9., 10.])}

get_x_defaults(): Get default values for x from parameter.

class fmdtools.sim.sample.ParameterHistSample(res, *varnames, comp_groups={}, **kwargs)

Bases: ParameterResultSample

Class for sampling parameters from Histories. Extends ParameterResultSample.

Examples

>>> from fmdtools.define.container.parameter import ExampleParameter
>>> expd = ParameterDomain(ExampleParameter)
>>> expd.add_variables("y")
>>> from fmdtools.analyze.history import History
>>> hist = History({'scen1.a.y': [1.0, 2.0, 3.0], 'scen1.time':[0,2,3], 'scen2.a.y': [10.0, 20.0, 30.0], 'scen2.time':[0,2,3]})
>>> phs = ParameterHistSample(hist, 'a.y', paramdomain=expd)
>>> phs.get_param_ins(rep=0, t=0)
[1.0]
>>> phs.get_param_ins(rep=1, t=1)
[20.0]

# Add scenarios to the sample >>> phs.add_hist_times(‘default’, ‘scen1’) >>> [s.p for s in phs.scenarios()] [{‘y’: 1.0}, {‘y’: 2.0}, {‘y’: 3.0}]

add_hist_groups(comp_groups=['default'], reps='all', ts='all', **kwargs)

Add scenarios in the comp_groups over given replicates and times.

Parameters:

comp_groups (list) – Names of the comparison group to get the values from.
reps (int/str/list) – If int, the number of replicates to sample. If a list, the names of the replicate scenarios to sample. If ‘all’, all replicates in the group.
ts (int/list/tuple/'all') – If ‘all’, returns all times. If int, returns a range of times with ts resolution. If a list (of ints), uses as ts_to_sample. IF a tuple, returns a range with the given input arguments.
**kwargs (kwargs) – Keyword arguments to .add_hist_scenario

add_hist_reps(comp_group, reps='all', ts='all', ind_seeds=True, **kwargs)

Add scenarios in the scenario comp_group over given replicates and times.

Parameters:

comp_group (str) – Name of the comparison group to get the value from.
reps (int/str/list) – If int, the number of replicates to sample. If a list, the names of the replicate scenarios to sample. If ‘all’, all replicates in the group.
ts (int/list/tuple/'all') – If ‘all’, returns all times. If int, returns a range of times with ts resolution. If a list (of ints), uses as ts_to_sample. IF a tuple, returns a range with the given input arguments.
ind_seeds (bool) – Whether to give replicates independent seeds. The default is True.
**kwargs (kwargs) – Keyword arguments to .add_hist_scenario

add_hist_scenario(comp_group='default', rep=1, t=1, name='hist', **kwargs): Add a scenario from a history (extends add_res_scenario).

add_hist_times(comp_group, rep, ts='all', **kwargs)

Add scenarios in the scenario comp_group and replicate from the given times.

Parameters:

comp_group (str) – Name of the comparison group to get the value from.
rep (str) – Name of the replicate scenario to get the value from.
ts (int/list/tuple/'all') – If ‘all’, returns all times. If int, returns a range of times with ts resolution. If a list (of ints), uses as ts_to_sample. IF a tuple, returns a range with the given input arguments.
**kwargs (kwargs) – Keyword arguments to .add_hist_scenario

class fmdtools.sim.sample.ParameterResultSample(res, *varnames, comp_groups={}, **kwargs)

Bases: ParameterSample

Class for sampling parameters from Results.

Parameters:

vars (tuple) – Variables to sample from the Result.
res_to_sample (Result) – Subset of input result associated with the variables/groups to sample.

Examples

>>> from fmdtools.define.container.parameter import ExampleParameter
>>> expd = ParameterDomain(ExampleParameter)
>>> expd.add_variables("y")
>>> from fmdtools.analyze.result import Result
>>> res = Result({'scen1.a.y': 1.0, 'scen2.a.y': 2.0})
>>> prs = ParameterResultSample(res, 'a.y', paramdomain=expd)
>>> prs.get_param_ins(rep=0)
[1.0]
>>> prs.get_param_ins(rep=1)
[2.0]

# prs.add_res_scenario can be used to add a given scenario from the result. >>> prs.add_res_scenario(rep=0) >>> prs.scenarios() [ParameterScenario(sequence={}, times=(), p={‘y’: 1.0}, r={}, sp={}, prob=1.0, inputparams={‘comp_group’: ‘default’, ‘rep’: 0}, rangeid=’’, name=’res_0’)]

# prs.add_res_reps can be used to add replicate scenarios from the results. >>> prs.add_res_reps(reps=’all’) >>> prs ParameterSample of scenarios:

res_0

res_1

res_2

add_res_reps(comp_group='default', reps='all', name='res', ind_seeds=True, **kwargs)

Add multiple scenario replicates from the Restul to the ParameterResultSample.

Parameters:

comp_group (str) – Name of the comparison group to get the value from.
reps (int/str/list) – If int, the number of replicates to sample. If a list, the names of the replicate scenarios to sample. If ‘all’, all replicates in the group.
name (str, optional) – Name prefix for the scenarios. The default is ‘res’.
ind_seeds (bool) – Whether to give replicates independent seeds. The default is True.
**kwargs (kwargs) – Keyword arguments to ParameterScenario.add_res_scenario.

add_res_scenario(comp_group='default', rep=1, t=None, name='res', **kwargs)

Add a scenario to the ParameterResultSample from the Result.

Parameters:

comp_group (str) – Name of the comparison group to get the value from.
rep (str) – Name of the replicate scenario to get the value from.
t (int/None, optional) – If a History, the time to get. The default is None.
name (str, optional) – Name prefix for the scenario. The default is ‘res’.
**kwargs (kwargs) – Keyword arguments to ParameterSample.add_variable_scenario.

get_param_ins(comp_group='default', rep=1, t=None)

Get the parameter values at the given Result scenario.

Parameters:

comp_group (str) – Name of the comparison group to get the value from.
rep (str) – Name of the replicate scenario to get the value from.
t (int/None, optional) – If a History, the time to get. The default is None.

Returns:

param_list – List of variable values (self.vars) for the given group and replicate.

Return type:

list

class fmdtools.sim.sample.ParameterSample(paramdomain=ParameterDomain with: - variables: {} - constants: {} - parameter_initializer: Parameter, seed=None, sp={})

Bases: BaseSample

Class for sampling parameters and other immutable model attributes.

…

seed

Seed for random sampling.

Type:: int

seedsequence

Corresponding seed sequence

Type:: np.ramdom.SeedSequence

sp

Non-default simparam arguments

Type:: dict

paramdomain

Parameter domain object to sample

Type:: ParamDomain

add_variable_ranges(combmethod='product', comb_kwargs={}, n_samp=False, name='range', **rep_kwargs)

Combine and add a set of ranges to the ParamSample.

Parameters:

combmethod (str, optional) – Name of the combination method (‘product’, ‘orthogonal’, ‘random’) for the class. The default is ‘product’.
comb_kwargs (dict, optional) – Keyword arguments to the self.combine_’methodname’. The default is {}.
n_samp (int, optional) – Number of values to randomly sample from the set of combinations. The default is False, which samples all.
name (str, optional) – Name for the range. The default is ‘range’.
**rep_kwargs (kwargs) – kwargs to add_variable_replicates (seed, weight, etc.).

Examples

>>> ex_ps = ParameterSample(expd)
>>> ex_ps.add_variable_ranges()
>>> ex_ps
ParameterSample of scenarios:
 - rep0_range_0
 - rep0_range_1
 - rep0_range_2
 - rep0_range_3
 - rep0_range_4
 - rep0_range_5
 - rep0_range_6
 - rep0_range_7
 - rep0_range_8
 - rep0_range_9
 - ... (44 total)

>>> ex_ps2 = ParameterSample(expd)
>>> ex_ps2.add_variable_ranges(n_samp=5)
>>> ex_ps2
ParameterSample of scenarios:
 - rep0_range_0
 - rep0_range_1
 - rep0_range_2
 - rep0_range_3
 - rep0_range_4

add_variable_replicates(x_combos, replicates=1, seed_comb='shared', name='var', weight=1.0)

Add replicates for the given cominations of variables.

Parameters:

x_combos (list) – List of combinations of variable values. [x_1, x_2…]. If empty, the default values of x are used.
replicates (int, optional) – Number of replicates to add of the variable. The default is 1.
seed_comb (str, optional) – How to combine seeds (‘shared’ or ‘independent’). ‘shared’ uses the same seed for each value while ‘independent’ uses different seeds over all variable values. The default is ‘shared’.
name (str, optional) – Name prefix for the set of replicates. The default is ‘var’.
weight (float, optional) – Total weight for the replicates (i.e., total probability to divide between samples). The default is 1.0.

Examples

>>> ex_ps = ParameterSample(expd)
>>> ex_ps.add_variable_replicates([[1,1], [2,2]])
>>> ex_ps
ParameterSample of scenarios:
 - rep0_var_0
 - rep0_var_1
>>> scen0 =ex_ps.scenarios()[0]
>>> scen0.prob
0.5
>>> scen0.p['x']
1
>>> scen0.p['y']
1
>>> scen0.inputparams
{0: 1, 1: 1}
>>> scen1 =ex_ps.scenarios()[1]
>>> scen1.prob
0.5
>>> scen1.p['x']
2
>>> scen1.p['y']
2
>>> scen1.inputparams
{0: 2, 1: 2}

add_variable_scenario(*x, seed=False, sp={}, weight=1.0, name='var', inputparams={})

Add a scenario to the ParamSample.

Parameters:

*x (vars) – Values of the variables defined in the parameter domain.
seed (int, optional) – Seed to include in the ParameterScenario. The default is False.
sp (dict, optional) – SimParam arguments to the ParameterScenario. The default is {}.
weight (float, optional) – Weight (probability) allocated to the scenario. The default is 1.0.
name (str, optional) – Name to assign the scenario. The default is ‘param’.
inputparams (dict, optional) – Input parameters (if different from Parameter input).

Examples

>>> ex_ps = ParameterSample(expd)
>>> ex_ps.add_variable_scenario(1, 2)
>>> ex_ps
ParameterSample of scenarios:
 - var_0
>>> ex_ps.scenarios()[0].p['z']
20
>>> ex_ps.scenarios()[0].p['y']
1
>>> ex_ps.scenarios()[0].p['x']
2

combine_orthogonal(resolution=1, resolutions={})

Create combinations of orthogonal arrays from the parameter domain.

Parameters:

resolution (float, optional) – Default resolution for the ranges. The default is 1.
resolutions (dict, optional) – Resolution for each individual range if not default. The default is {}.

Returns:

x_combos – List of combinations of x.

Return type:

list

Examples

>>> ex_ps = ParameterSample(expd, seed=1)
>>> ex_ps.combine_orthogonal()
[[1.0, 1.0], [2.0, 1.0], [3.0, 1.0], [4.0, 1.0], [3.0, 0], [3.0, 1], [3.0, 2], [3.0, 3], [3.0, 4], [3.0, 5], [3.0, 6], [3.0, 7], [3.0, 8], [3.0, 9], [3.0, 10]]

combine_product(resolution=1, resolutions={})

Find all combinations of possible range values.

Parameters:

resolution (float, optional) – Default resolution for the ranges. The default is 1.
resolutions (dict, optional) – Resolution for each individual range if not default. The default is {}.

Returns:

x_combos – List of combinations of x.

Return type:

list

Examples

>>> ex_ps = ParameterSample(expd, seed=1)
>>> ex_ps.combine_product()
[(1.0, 0), (1.0, 1), (1.0, 2), (1.0, 3), (1.0, 4), (1.0, 5), (1.0, 6), (1.0, 7), (1.0, 8), (1.0, 9), (1.0, 10), (2.0, 0), (2.0, 1), (2.0, 2), (2.0, 3), (2.0, 4), (2.0, 5), (2.0, 6), (2.0, 7), (2.0, 8), (2.0, 9), (2.0, 10), (3.0, 0), (3.0, 1), (3.0, 2), (3.0, 3), (3.0, 4), (3.0, 5), (3.0, 6), (3.0, 7), (3.0, 8), (3.0, 9), (3.0, 10), (4.0, 0), (4.0, 1), (4.0, 2), (4.0, 3), (4.0, 4), (4.0, 5), (4.0, 6), (4.0, 7), (4.0, 8), (4.0, 9), (4.0, 10)]

combine_random(num_combos=1)

Create combinations of random variables from the parameter domain.

Parameters:: num_combos (int, optional) – Number of combinations. The default is 1.
Returns:: x_combos – List of list of combinations.
Return type:: list

Examples

>>> ex_ps = ParameterSample(expd, seed=1)
>>> ex_ps.combine_random(1)
[[2.0, 9.504636963259353]]

scenarios(): Return list of scenarios that make up the ParameterSample.

class fmdtools.sim.sample.SampleApproach(mdl, phasemaps={}, def_mdl_phasemap=True)

Bases: BaseSample

Class for defining an agglomeration of fault samples accross an entire model.

mdl

Model

Type:: Simulable

phasemaps

Dict of phasemaps {‘phasemapname’: PhaseMap} which map to the various functions of the model.

Type:: dict

faultdomains

Dict of the faultdomains to sample {‘domainname’: FaultDomain}

Type:: dict

faultsamples

Dict of the FaultSamples making up the approach {‘samplename’: FaultSample}

Type:: dict

add_faultdomain(name, add_method, *args, **kwargs)

Instantiate and associates a FaultDomain with the SampleApproach.

Parameters:

name (str) – Name to give the faultdomain (in faultdomains).
add_method (str) – Method to add faults to the faultdomain with (e.g., to call Faultdomain.add_all, use “all”)
*args (args) – Arguments to add_method.
**kwargs (kwargs) – Keyword arguments to add_method

Examples

>>> from examples.multirotor.drone_mdl_rural import Drone
>>> s = SampleApproach(Drone())
>>> s.add_faultdomain("all_faults", "all")
>>> s
SampleApproach for drone with:
 faultdomains: all_faults
 faultsamples:
>>> s.faultdomains['all_faults']
FaultDomain with faults:
 -('manage_health', 'lostfunction')
 -('store_ee', 'nocharge')
 -('store_ee', 'lowcharge')
 -('store_ee', 's1p1_short')
 -('store_ee', 's1p1_degr')
 -('store_ee', 's1p1_break')
 -('store_ee', 's1p1_nocharge')
 -('store_ee', 's1p1_lowcharge')
 -('dist_ee', 'short')
 -('dist_ee', 'degr')
 -...more

add_faultdomains(**faultdomains)

Add dict of faultdomains to the SampleApproach.

Parameters:: **faultdomains (tuple) – FaultDomains to add to the SampleApproach and their arguments. Has structure:: {‘fd_name’: (*args, **kwargs)} where args and kwargs are arguments/kwargs to SampleApproach.add_faultdomain (after name).

add_faultsample(name, add_method, faultdomains, *args, phasemap={}, **kwargs)

Instantiate and associate a FaultSample with the SampleApproach.

Parameters:

name (str) – Name for the faultsample.
add_method (str) – Method to add scenarios to the FaultSample with. (e.g., to call Faultdomain.add_fault_times, use “fault_times”)
faultdomain (str or list) – Name of faultdomain to sample from (must be in SampleApproach already).
*args (args) – args to add_method.
phasemap (str/PhaseMap/dict/tuple, optional) – Phasemap to instantiate the FaultSample with. If a dict/tuple is provided, uses a PhaseMap with the dict/tuple as phases. The default is {}. If a list, passes to JointFaultSample
**kwargs (kwargs) – add_method kwargs.

Examples

>>> from examples.multirotor.drone_mdl_rural import Drone
>>> s = SampleApproach(Drone())
>>> s.add_faultdomain("all_faults", "all")
>>> s.add_faultsample("start_times", "fault_times", "all_faults", [1,3,4])
>>> s
SampleApproach for drone with:
 faultdomains: all_faults
 faultsamples: start_times
>>> s.faultsamples['start_times']
FaultSample of scenarios:
 - manage_health_lostfunction_t1
 - manage_health_lostfunction_t3
 - manage_health_lostfunction_t4
 - store_ee_nocharge_t1
 - store_ee_nocharge_t3
 - store_ee_nocharge_t4
 - store_ee_lowcharge_t1
 - store_ee_lowcharge_t3
 - store_ee_lowcharge_t4
 - store_ee_s1p1_short_t1
 - ... (171 total)

add_faultsamples(**faultsamples)

Add dict of faultsamples to the SampleApproach.

Parameters:: **faultsamples (tuple) – FaultSamples to add to othe SampleApproach and their arguments. Has structure:: fs_name = (*args, **kwargs)} where args and kwargs are arguments/kwargs to SampleApproach.add_faultsample (after name).

prune_scenarios(scen_var='rate', comparator=<ufunc 'greater'>, value=0.0)

Prune scenarios from the FaultSample.

Parameters:

scen_var (str, optional) – Variable to prune. The default is ‘rate’.
comparator (method, optional) – Numpy method. The default is np.greater_equal.
value (float, optional) – Value to compare against. The default is 0.0.

scenarios(): Get all scenarios in the SampleApproach.

times(): Get all sampletimes covered by the SampleApproach.

fmdtools.sim.sample.combine_orthogonal(defaults, ranges)

Create an orthogonal arrays (lists) over the given ranges.

Parameters:

defaults (tuple) – Default variables
ranges (list) – List of lists of non-default values for each value

Returns:

samples – List of lists of orthogonal x.

Return type:

list

Examples

>>> combine_orthogonal([1,1], [[0,2], [3,4]])
[[0, 1], [2, 1], [1, 3], [1, 4]]

fmdtools.sim.sample.combine_random(ranges, seed=None, num_combos=1)

Create random lists from the given ranges.

Parameters:

ranges (list) – List of potential values (sets) or limits (tuples).
seed (seed, optional) – Seed to sample with. The default is 0.
num_combos (int, optional) – Number of combinations to sample. The default is 1.

Returns:

x_combos – List of potential combinations.

Return type:

list

Examples

>>> x_comb = combine_random([{1,2,3}, (0, 1)])
>>> x_comb[0][0] in {1, 2, 3}
True
>>> 0 <= x_comb[0][1] <= 1
True

fmdtools.sim.sample.pass_var(*x)

fmdtools.sim.sample.same_mode(modename1, modename2, exact=True): Check if modename1 and modename2 are the same.

fmdtools.sim.sample.sample_times_even(times, numpts, dt=1.0)

Get sample time for the number of points from sampling evenly.

Parameters:

times (list) – Times to sample.
numpts (int) – Number of points to sample.

Returns:

sampletimes (list) – List of times to sample
weights (list) – Weights.

Examples

>>> sample_times_even([0.0, 1.0, 2.0, 3.0, 4.0], 2)
([1.0, 3.0], [0.5, 0.5])

fmdtools.sim.sample.sample_times_quad(times, nodes, weights)

Get the sample times for the given quadrature defined by nodes and weights.

Parameters:

times (list) – Times to sample.
nodes (nodes) – quadrature nodes (ranging between -1 and 1)
weights (weights) – corresponding quadrature weights

Returns:

sampletimes (list) – List of times to sample
weights (list) – Weights.

Examples

>>> sample_times_quad([0,1,2,3,4], [-0.5, 0.5], [0.5, 0.5])
([1, 3], [0.5, 0.5])

fmdtools.sim.sample.x_to_kwargs(constants, variables, *x): Convert x over the defined variables into a set of kwargs.

fmdtools.sim.search

Description: Functions and Classes to enable optimization and search of fault model states and parameters.

Classes:

ProblemArchitecture: Enables the representation of combined joint optimization problems
DynamicInterface: Creates an interface for model simulations for dynamic optimization of a single sim
SimpleProblem: Creates an interface for simple optimazation problem without any model constructs
DisturbanceProblem: Enables optimizing disturbances that occur at a set time
SingleFaultScenarioProblem: Enables optimizing the time of a given fault scenario

class fmdtools.sim.search.BaseConnector

Bases: dataobject

Base class for connectors.

Connectectors are used in ProblemArchitectures to link the outputs of one problem as the inputs to another.

…

name : name to give the Connector

name: str

class fmdtools.sim.search.BaseObjCon

Bases: dataobject

Base class for objectives and constraints.

…

namestr: Name of the objective/constraint
valuefloat: Value of the objective/constraint

name: str

value: float

class fmdtools.sim.search.BaseProblem

Bases: object

Base optimization problem.

…

variables

Variables being optimized.

Type:: dict

objectives

Objectives returned.

Type:: dict

constraints

Constraints returned.

Type:: dict

add_constraint(name, varname, conclass=<class 'fmdtools.sim.search.Constraint'>, **kwargs): Add a constraint to the Problem.

add_constraint_callable(name): Add callable constraint function with name name.

add_objective(name, varname, objclass=<class 'fmdtools.sim.search.Objective'>, **kwargs): Add an objective to the Problem.

add_objective_callable(name): Add callable objective function with name.

call_constraint(*x, constraint=''): Call a given constraint at x.

call_objective(*x, objective=''): Call a given objective at x.

call_outputs(*x, force_update=False)

Get all outputs at the given value of x.

Parameters:

*x (values) – Variable values

Returns:

objectives (list) – values of the objectives
constraints (list) – values of the constraints

current_x(): Get the current variable value x.

get_constraints(): Get all current constraint values.

get_default_x(*x)

get_objectives(): Get all current objective values.

log_hist(): Log the history for objectives, constraints, time, etc.

log_time()

name_repr(): Single-line name representation.

new_x(*x): Check if a given x is the same as the current value of x.

prob_repr(): Representation of the problem variables, objectives, constraints.

time_execution(*x, reps=1)

Time the amount of time it takes to update the problem.

Parameters:

*x (vars) – Variable values to execute at, optional. If not provided, uses the current values.
reps (int, optional) – Number of replicates to average/loop over. The default is 1.

Returns:

t_ave – Avarage time over all replicates

Return type:

float

update_variables(*x): Update variables at x.

class fmdtools.sim.search.BaseSimProblem(mdl, prop_method, *args, **kwargs)

Bases: BaseProblem

Base optimization problem for optimizing over simulations.

…

prop_method

Method in propagate to call.

Type:: callable

add_history_constraint(name, varname, **kwargs): Add an objective corresponding to a given history attribute.

add_history_objective(name, varname, **kwargs): Add an objective corresponding to a given history attribute.

add_result_constraint(name, varname, **kwargs)

Add an objective corresponding to a possible desired_result.

Associates a callable to the problem with name ‘name’ which may be called to evaluate the constraint at a value of x.

Parameters:

name (str) – Name to give the constraint.
varname (str) – Name of the variable to get for the constraint.
**kwargs (kwargs) – Arguments to ResultConstraint

add_result_objective(name, varname, **kwargs)

Add an objective corresponding to a possible desired_result.

Associates a callable to the problem with name ‘name’ which may be called to evaluate the objective at a value of x.

Parameters:

name (str) – Name to give the objective
varname (str) – Name of the variable to get for the variable.
**kwargs (kwargs) – Arguments to ResultObjective

get_end_time()

Get the end_time for the simulation that minimizes simulation time.

Used so that simulations only run until the last objective is called, rather than the full set of potential timesteps.

Returns:: end_time – Simulation time to simulate to.
Return type:: float

obj_con_des_res()

Get the desired_result argument for the problem given objectives/constraints.

Returns:: des_res – desired_result argument to prop_method.
Return type:: dict

update_objectives(*x): Update objectives/constraints by simulating the model at x.

class fmdtools.sim.search.Constraint

Bases: Objective

Base class for constraints which derive from results.

…

thresholdfloat: Theshold for the constraint. Default is 0.0
comparatorstr: Whether the constraint is ‘greater’ or ‘less’.
satisfiedbool: Whether the constraint is satisfied.

comparator: str

con_from_value(value)

Get the constraint given the value of its variable given threshold.

By default, constraints follow the form:: g(x) = threshold - value > 0.0 for ‘greater’ constraints or g(x) = value - theshold > 0.0 for ‘less’ constraints.

Parameters:: value (float) – Variable value corresponding to the constraint
Returns:: con – Constraint function at value.
Return type:: float

name: str

negative: bool

satisfied: bool

threshold: float

update(value): Update with given value.

value: float

class fmdtools.sim.search.ConstraintConnector(*args, **kwargs)

Bases: ObjectiveConnector

Class for linking constraints. Same as VariableConnector but used differently.

keys: tuple

name: str

values: array

class fmdtools.sim.search.DisturbanceProblem(mdl, time, *disturbances, **kwargs)

Bases: ScenarioProblem

Class for optimizing disturbances that occur at a set time.

gen_scenario(*x)

Generate the scenario to simulate in the model.

Parameters:: x (float) – Fault scenario time.
Returns:: scen – SingleFaultScenario to simulate.
Return type:: SingleFaultScenario

get_start_time(): Get the scenario start time to copy the model at.

class fmdtools.sim.search.DynamicInterface(mdl, mdl_kwargs={}, t_max=False, track='all', run_stochastic='track_pdf', desired_result=[], use_end_condition=None)

Bases: object

Interface for dynamic search of model states (e.g., AST).

…

t

time

Type:: float

t_max

max time

Type:: float

t_ind

time index in log

Type:: int

desired_result

variables to get from the model at each time-step

Type:: list

hist

mdlhist for simulation

Type:: History

check_sim_end(external_condition=False)

Check the model end-condition (and sim time) and clips the simulation log.

Parameters:: external_condition (bool, optional) – External end-condition to trigger simulation end. The default is False.
Returns:: end – Whether the simulation is finished
Return type:: bool

update(seed={}, faults={}, disturbances={})

Update the model states at the simulation time and iterates time.

Parameters:

seed (seed, optional) – Seed for the simulation. The default is {}.
faults (dict, optional) – faults to inject in the model, with structure {fxn:[faults]}. The default is {}.
disturbances (dict, optional) – Variables to change in the model, with structure {fxn.var:value}. The default is {}.

Returns:

returns – dictionary of returns with values corresponding to desired_result

Return type:

dict

class fmdtools.sim.search.HistoryConstraint

Bases: ResultConstraint

Same as ResultConstraint but with different name.

comparator: str

metric: callable

name: str

negative: bool

satisfied: bool

threshold: float

time: float

value: float

class fmdtools.sim.search.HistoryObjective

Bases: ResultObjective

Same as ResultObjective but marks that the result is a history.

Examples

>>> obj = HistoryObjective("a.b", metric=np.max)
>>> hist = History({'t1p0.a.b': [5.0, 10.0], 't2p0.a.b': [1.0, 13.0]})
>>> obj.get_result_value(hist)
13.0

metric: callable

name: str

negative: bool

time: float

value: float

class fmdtools.sim.search.Objective

Bases: BaseObjCon

…

negativebool: Whether the objective is the negative of the value.

name: str

negative: bool

obj_from_value(value): Get the (+ or 0) objective corresponding to value give self.negative.

update(value): Update with given value.

value: float

class fmdtools.sim.search.ObjectiveConnector(*args, **kwargs)

Bases: VariableConnector

Class for linking objectives. Same as VariableConnector but used differently.

keys: tuple

name: str

update(valuedict)

Update the value of the connector given a dict of values.

Parameters:: valuedict (dict) – dict with structure {k: value}, where k corresponds to a key in self.keys.

values: array

class fmdtools.sim.search.ParameterSimProblem(mdl, parameterdomain, prop_method, *args, **kwargs)

Bases: BaseSimProblem

Optimization problem defining the optimization of model parameters over simulations.

Examples

>>> from fmdtools.sim.sample import expd
>>> from fmdtools.define.block.function import ExampleFunction

below, we show basic setup of a parameter problem where objectives get values from the sim at particular times.

>>> exprob = ParameterSimProblem(ExampleFunction(), expd, "nominal")
>>> exprob.add_result_objective("f1", "s.x", time=5)
>>> exprob.add_result_objective("f2", "s.y", time=5)
>>> exprob.add_result_constraint("g1", "s.x", time=10, threshold=10, comparator='greater')
>>> exprob
ParameterSimProblem with:
VARIABLES
 -y                                                             nan
 -x                                                             nan
OBJECTIVES
 -f1                                                            nan
 -f2                                                            nan
CONSTRAINTS
 -g1                                                            nan

once this is set up, you can use the objectives/constraints as callables, like so:

>>> exprob.f1(1, 0)
0.0
>>> exprob.f1(1, 1)
5.0
>>> exprob.f1(1, 2)
10.0
>>> exprob.f2(1, 2)
0.0
>>> exprob.g1(1, 2)
-10.0

below, we use the endclass as an objective instead of the variable:

>>> exprob = ParameterSimProblem(ExampleFunction(), expd, "nominal")
>>> exprob.add_result_objective("f1", "endclass.xy")
>>> exprob.f1(1, 1)
100.0
>>> exprob.f1(1, 2)
200.0

finally, note that this class can work with a variety of methods:

>>> exprob = ParameterSimProblem(ExampleFunction("ex"), expd, "one_fault", "ex", "short", 2)
>>> exprob.add_result_objective("f1", "s.y", time=3)
>>> exprob.add_result_objective("f2", "s.y", time=5)
>>> exprob.f1(1, 1)
2.0
>>> exprob.f2(1, 1)
4.0

sim_mdl(*x)

Simulate the model at the given variable value.

Parameters:

*x (args) – Variable inputs for parameterdomain.

Returns:

res (Result) – result for the sim.
hist (History) – history for the sim.

class fmdtools.sim.search.ProblemArchitecture

Bases: BaseProblem

Class enabling the representation of combined joint optimization problems.

Combined optimization problems involve multiple variables and objectives which interact (e.g., Integrated Resilience Optimization, Two-Stage Optimization, etc.)

Note that ProblemArchitectures are (presently) limited in the sense that they assume problems are sequentially linked in the order of instantiation. While this works well for nested problems, there are some limitations when workign with parallel problems which we hope to resolve in future work.

…

connectors

Dictionary of Connector (variables, models, etc) added using .add_connector

Type:: dict

problems

Dictionary of optimization problems added using .add_problem

Type:: dict

problem_graph

Graph structure containing information about how each problem is connected.

Type:: nx.DiGraph

var_mapping

Dict mapping inputs to each problem to problem variables.

Type:: dict

Examples

Below we connect three example problems in a single architecture, linking the vars x0 and x1 from ex_sp to be inputs to the scenario simulation (time) as well as the disturbance simulation variable (s.y).

>>> ex_pa = ProblemArchitecture()
>>> ex_pa.add_connector_variable("x0", "x0")
>>> ex_pa.add_connector_variable("x1", "x1")
>>> ex_pa.add_problem("ex_sp", ex_sp, outputs={"x0": ["x0"], "x1": ["x1"]})
>>> ex_pa.add_problem("ex_scenprob", ex_scenprob, inputs={"x0": ["time"]})
>>> ex_pa.add_problem("ex_dp", ex_dp, inputs={"x1": ["s.y"]})
>>> ex_pa
ProblemArchitecture with:
CONNECTORS
 -x0                                                          [nan]
 -x1                                                          [nan]
PROBLEMS
 -ex_sp({'ex_sp_xloc': ['x0', 'x1']}) -> ['x0', 'x1']
 -ex_scenprob({'x0': ['time']}) -> []
 -ex_dp({'x1': ['s.y']}) -> []
VARIABLES
 -ex_sp_xloc                                              [nan nan]
OBJECTIVES
 -ex_sp_f1                                                      nan
 -ex_scenprob_f1                                                nan
 -ex_dp_f1                                                      nan
CONSTRAINTS
 -ex_sp_g1                                                      nan

Setting up this problem gives us callables for each problem which we can use to call each objective in each problem in terms of its local variables:

>>> ex_pa.ex_sp_f1(1, 1)
2.0
>>> ex_pa.ex_scenprob_f1()
16.0
>>> ex_pa.ex_dp_f1()
1.0

We can also call these in terms of the full set of variables:

>>> ex_pa.ex_scenprob_f1_full(2, 2)
13.0
>>> ex_pa.ex_dp_f1_full(3, 3)
3.0

add_connector(name, *args, conclass=<class 'fmdtools.sim.search.VariableConnector'>)

Add a connector linking variables between problems.

Parameters:

name (str) – Name for the connector
*args (strs) – arguments to conclass
conclass (Connector) – Class to instantiate.

add_connector_constraint(name, *connames)

Add a connector linking a constraint to an input variable in another problem.

Parameters:

name (str) – Name for the connector
*varnames (strs) – Names of the constraint values to link as a part of the connector.

add_connector_objective(name, *objnames)

Add a connector linking an objective to an input variable in another problem.

Parameters:

name (str) – Name for the connector
*objnames (strs) – Names of the objective values to link as a part of the connector.

add_connector_variable(name, *varnames)

Add a connector linking variables between problems.

Parameters:

name (str) – Name for the connector
*varnames (strs) – Names of the variable values (used in each problem) to link as a part of the connector.

add_constraint_callable(probname, conname): Add callable constraint function from problem probname.

add_constraint_callables(probname): Add callable constraint function from problem probname.

add_objective_callable(probname, objname): Add callable objective function from problem probname.

add_objective_callables(probname): Add callable objective functions from problem.

add_problem(name, problem, inputs={}, outputs={})

Add a problem to the ProblemArchitecture.

Parameters:

name (str) – Name for the problem.
problem (BaseProblem/ScenProblem/SimpleProblem...) – Problem object to add to the architecture.
inputs (dict, optional) – List of input connector names (by name) and their corresponding problem variables. The default is [].
outputs (dict, optional) – List of output connector names (by name) and their corresponding problem variables/objectives/constraints. The default is [].

call_constraint(probname, conname, *x_loc): Call constraint of a problem over partial its local variables *x_loc.

call_full_constraint(probname, conname, *x_full): Call objective of a problem over full set of variables *x_full.

call_full_objective(probname, objname, *x_full): Call objective of a problem over full set of variables *x_full.

call_objective(probname, objname, *x_loc): Call objective of a problem over partial its local variables *x_loc.

create_var_mapping(probname): Create a dict mapping problem variables to input/connector variables.

find_inconsistent_upstream(probname): Check that all upstream problems are consistent with current probname.

find_input_vars(probname): Find variables for a problem that are in an input connector.

find_inputs(probname)

List input connectors for a given problem.

Parameters:: probname (str) – Name of the problem.
Returns:: inputs – List of names of connectors used as inputs.
Return type:: list

find_outputs(probname)

List output connectors for a given problem.

Parameters:: probname (str) – Name of the problem.
Returns:: outputs – List of names of connectors used as outputs.
Return type:: list

find_xloc_vars(probname): Find variables for a problem that aren’t in an input connector.

get_default_x(*x)

get_downstream_probs(probname): Return a list of all problems to be executed after the problem probname.

get_inputs(probname): Return a dict of input connectors for problem probname.

get_inputs_as_x(probname, *x)

Get variable values for inputs.

Parameters:: probname (str) – Name of the problem..
Returns:: inputs – Input connectors and their values.
Return type:: list

get_outputs(probname): Return a dict of output connectors for problem probname.

get_upstream_probs(probname): Return a list of all problems to be executed before the problem probname.

prob_repr(): Representation of the problem variables, objectives, constraints.

show_sequence()

Show a visualization of the problem architecture.

Returns:

fig (mpl.figure) – Figure object.
ax (mpl.axis) – Axis object.

update_downstream_consistency(probname): Mark downstream problems as inconsistent (when current problem updated).

update_full_problem(*x_full, probname='', force_update=False)

Update the variables for the entire problem (or, problems up to probname).

Parameters:

*x_full (float) – Variable values for all local variables in the problem architecture up to the probname.
probname (str, optional) – If provided, the problems will be updated up to the given problem. The default is ‘’.

Examples

>>> ex_pa.update_full_problem(1, 2)
>>> ex_pa
ProblemArchitecture with:
CONNECTORS
 -x0                                                           [1.]
 -x1                                                           [2.]
PROBLEMS
 -ex_sp({'ex_sp_xloc': ['x0', 'x1']}) -> ['x0', 'x1']
 -ex_scenprob({'x0': ['time']}) -> []
 -ex_dp({'x1': ['s.y']}) -> []
VARIABLES
 -ex_sp_xloc                                                [1. 2.]
OBJECTIVES
 -ex_sp_f1                                                   3.0000
 -ex_scenprob_f1                                            16.0000
 -ex_dp_f1                                                   2.0000
CONSTRAINTS
 -ex_sp_g1                                                  -4.0000

>>> ex_pa.problems['ex_dp']
DisturbanceProblem with:
VARIABLES
 -s.y                                                        2.0000
OBJECTIVES
 -f1                                                         2.0000

update_objectives(*x): Take place of update_objectives in base problem.

update_problem(probname, *x, force_update=False)

Update a given problem with new values for inputs (and non-input variables).

Additionally updates output connectors.

Parameters:

probname (str) – Name of the problem to update.
*x (float) – Input variables to update (aside from inputs).

Examples

>>> ex_pa.update_problem("ex_sp", 1, 2)
>>> ex_pa.problems["ex_sp"]
SimpleProblem with:
VARIABLES
 -x0                                                         1.0000
 -x1                                                         2.0000
OBJECTIVES
 -f1                                                         3.0000
CONSTRAINTS
 -g1                                                        -4.0000

This update should further update connectors:

>>> ex_pa.get_outputs("ex_sp")
{'x0': VariableConnector(name='x0', keys=('x0',), values=array([1.])), 'x1': VariableConnector(name='x1', keys=('x1',), values=array([2.]))}

Which should then propagate to downstream sims:

>>> ex_pa.update_problem("ex_scenprob")
>>> ex_pa.problems["ex_scenprob"]
SingleScenarioProblem(examplefunction, short) with:
VARIABLES
 -time                                                       1.0000
OBJECTIVES
 -f1                                                        16.0000

update_problem_constraints(probname): Update architecture-level constraints from problem.

update_problem_objectives(probname): Update architecture-level objectives from problem.

update_problem_outputs(probname)

Update the output connectors from a problem.

Parameters:: probname (str) – Name of the problem.

class fmdtools.sim.search.ResultConstraint

Bases: ResultObjective

Base class for constraints which derive from results.

…

thresholdfloat: Theshold for the constraint. Default is 0.0
comparatorstr: Whether the constraint is ‘greater’ or ‘less’.
satisfiedbool: Whether the constraint is satisfied.

comparator: str

con_from_value(value)

Call con_from_value from Constraint for the ResultConstraint.

Examples

>>> con = ResultConstraint("a", threshold=10.0, comparator='greater')
>>> con.con_from_value(11.0)
-1.0

>>> con2 = ResultConstraint("a", threshold=10.0, comparator='less')
>>> con2.con_from_value(11.0)
1.0

metric: callable

name: str

negative: bool

satisfied: bool

threshold: float

time: float

update(res): Update the value of the constraint given the result.

value: float

class fmdtools.sim.search.ResultObjective

Bases: Objective

Base class of objectives which derive from Results.

…

timefloat: Time the objective is called at. If None, time will be the end of the sim.
metriccallable: Metric to tabulate for the objective. Default is np.sum.

get_result_value(res)

Get the value corresponding to the objective from the result.

Parameters:: res (Result) – Result containing the metric desired.
Returns:: val – Value corresponding to the result.
Return type:: value

Examples

>>> from fmdtools.analyze.result import Result
>>> obj = ResultObjective("a.b", time=1.0)
>>> res = Result({'t1p0.a.b': 10.0, 't2p0.a.b': 13.0})
>>> obj.get_result_value(res)
10.0

>>> obj = ResultObjective("a.b", time=1.0, metric=np.sum)
>>> res = Result({'scen1.t1p0.a.b': 10.0, 'scen2.t1p0.a.b': 12.0})
>>> obj.get_result_value(res)
22.0

metric: callable

name: str

negative: bool

time: float

update(res): Update the value of the objective given the result.

value: float

class fmdtools.sim.search.ScenarioProblem(mdl, faultdomain=None, phasemap=None, **kwargs)

Bases: BaseSimProblem

Base class for optimizing scenario parameters.

prepped_sims

Dict of outputs from propagate.nom_helper. Used for staged execution of scenarios (where the model is copied instead of re-simulated).

Type:: dict

prep_sim(): Prepare simulation by simulating it until the start of the scenario.

sim_mdl(*x)

Simulate the model at the given variable value.

Parameters:

*x (args) – Variable inputs for parameterdomain.

Returns:

res (Result) – result for the sim.
hist (History) – history for the sim.

class fmdtools.sim.search.SimpleProblem(*variables)

Bases: BaseProblem

Simple optimization problem (without any given model constructs).

…

callables

dict of callables for objectives/constraints

Type:: dict

Examples

>>> ex_sp = SimpleProblem("x0", "x1")
>>> f1 = lambda x0, x1: x0 + x1
>>> ex_sp.add_objective("f1", f1)
>>> g1 = lambda x0, x1: x0 - x1
>>> ex_sp.add_constraint("g1", g1, threshold=3.0, comparator="less")

>>> ex_sp.f1(1, 1)
2
>>> ex_sp.g1(1, 1)
-3.0

add_constraint(name, call, **kwargs)

Add an constraint to the problem.

Parameters:

name (str) – Name for the objective.
call (callable) – Function to call for the objective in terms of the variables.
**kwargs (kwargs) – kwargs to Constraint

add_objective(name, call, **kwargs)

Add an objective to the problem.

Parameters:

name (str) – Name for the objective.
call (callable) – Function to call for the objective in terms of the variables.
**kwargs (kwargs) – kwargs to Objective.

update_objectives(*x): Update objectives/constraints by calling callables.

class fmdtools.sim.search.SingleFaultScenarioProblem(mdl, faulttup, phasemap=None, t_start=0.0, **kwargs)

Bases: ScenarioProblem

Class for optimizing the time of a given fault scenario.

…

faultdomain

FaultDomain containing the fault

Type:: FaultDomain

phasemap

PhaseMap for fault sampling

Type:: PhaseMap

t_start

Minimum start time for the simulation and lower bound on scenario time.. Default is 0.0.

Type:: float

Examples

>>> from fmdtools.define.block.function import ExampleFunction
>>> ex_scenprob = SingleFaultScenarioProblem(ExampleFunction(), ("examplefunction", "short"))
>>> ex_scenprob.add_result_objective("f1", "s.y", time=5)

objective value should be 1.0 (init value) + 3 * time_with_fault

>>> ex_scenprob.f1(5.0)
4.0
>>> ex_scenprob.f1(4.0)
7.0

gen_scenario(x)

Generate the scenario to simulate in the model.

Parameters:: x (float) – Fault scenario time.
Returns:: scen – SingleFaultScenario to simulate.
Return type:: SingleFaultScenario

get_start_time(): Get the scenario start time to copy the model at.

name_repr(): Get name of the class and faults.

class fmdtools.sim.search.VariableConnector(*args, **kwargs)

Bases: BaseConnector

Class connecting variables in one problem to use as variables in another problem.

keystuple: Names of the variables.
valuesnp.array: Array of values for the variables.

get(key, defaultval=None): Get a value for a particular key.

in_(k)

items()

keys: tuple

name: str

update(valuedict)

Update the value of the connector given a dict of values.

Parameters:: valuedict (dict) – dict with structure {k: value}, where k corresponds to a key in self.keys.

update_values(*x)

Update values of the connector given input variable x.

Parameters:: *x (iterable) – Variable values to update (must be in order of self.keys).

values: array

fmdtools.sim.search.f1(x0, x1)

fmdtools.sim.search.g1(x0, x1)

fmdtools.sim.search.obj_name(probname, objname): Create architecture-level objective name for problem.

fmdtools.sim.search.unpack_x(*x)