def _check_mod_set(self, mod_set, name):
"""
Checks validity of provided set of model outputs `mod_set` in this
:obj:`~ModelLink` instance.
Parameters
----------
mod_set : 1D or 2D array_like or dict
Model output (set) to validate in this :obj:`~ModelLink` instance.
name : str
The name of the model output (set), which is used in the error
message if the validation fails.
Returns
-------
mod_set : 1D or 2D :obj:`~numpy.ndarray` object
The provided `mod_set` if the validation was successful. If
`mod_set` was a dict, it will be converted to a
:obj:`~numpy.ndarray` object (sorted on :attr:`~data_idx`).
"""
# Make logger
logger = getCLogger('CHECK')
logger.info("Validating provided set of model outputs %r." % (name))
# If mod_set is a dict, try to convert it to a NumPy array
if isinstance(mod_set, dict):
try:
mod_set = np_array([mod_set[idx] for idx in self._data_idx]).T
except KeyError as error:
err_msg = (
"Input argument %r is missing data identifier '%r'!" %
(name, error.args[0]))
raise_error(err_msg, KeyError, logger)
# Make sure that mod_set is a NumPy array
mod_set = np_array(mod_set)
# Raise error if mod_set is not 1D or 2D
if not (mod_set.ndim == 1 or mod_set.ndim == 2):
err_msg = ("Input argument %r is not one-dimensional or "
"two-dimensional!" % (name))
raise_error(err_msg, ShapeError, logger)
# Raise error if mod_set does not have n_data data values
if not (mod_set.shape[-1] == self._n_data):
err_msg = ("Input argument %r has incorrect number of data values "
"(%i != %i)!" % (name, mod_set.shape[-1], self._n_data))
raise_error(err_msg, ShapeError, logger)
# Check if mod_set solely consists out of floats
mod_set = check_vals(mod_set, name, 'float')
# Log again and return mod_set
logger.info("Finished validating provided set of model outputs %r." %
(name))
return (mod_set)
def advance_chain(sam_set):
# Make sure that sam_set is 2D
sam_set = np_array(sam_set, ndmin=2)
# Check if sam_set is within parameter space and reject if not
par_rng = pipe._modellink._par_rng
accept = ((par_rng[:, 0] <= sam_set) *
(sam_set <= par_rng[:, 1])).all(1)
# Evaluate all non-rejected samples and accept if plausible
emul_i = pipe._emulator._emul_i
accept[accept] = pipe._make_call('_evaluate_sam_set', emul_i,
sam_set[accept], 'project')[0]
# Return which samples should be accepted or rejected
return (accept)
def _check_md_var(self, md_var, name):
"""
Checks validity of provided set of model discrepancy variances `md_var`
in this :obj:`~ModelLink` instance.
Parameters
----------
md_var : 1D or 2D array_like or dict
Model discrepancy variance set to validate in this
:obj:`~ModelLink` instance.
name : str
The name of the model discrepancy set, which is used in the error
message if the validation fails.
Returns
-------
md_var : 2D :obj:`~numpy.ndarray` object
The (converted) provided `md_var` if the validation was successful.
If `md_var` was a dict, it will be converted to a
:obj:`~numpy.ndarray` object.
"""
# Make logger
logger = getCLogger('CHECK')
logger.info("Validating provided set of model discrepancy variances "
"%r." % (name))
# If md_var is a dict, convert it to a NumPy array
if isinstance(md_var, dict):
md_var = np_array([md_var[idx] for idx in md_var.keys()])
# Make sure that md_var is a NumPy array
md_var = np_array(md_var)
# Raise error if md_var is not 1D or 2D
if not (md_var.ndim == 1 or md_var.ndim == 2):
err_msg = ("Input argument %r is not one-dimensional or "
"two-dimensional!" % (name))
raise_error(err_msg, ShapeError, logger)
# Check if md_var contains n_data values
if not (md_var.shape[0] == self._n_data):
err_msg = ("Received array of model discrepancy variances %r has "
"incorrect number of data points (%i != %i)!" %
(name, md_var.shape[0], self._n_data))
raise ShapeError(err_msg)
# Check if single or dual values were given
if (md_var.ndim == 1):
md_var = np_array([md_var] * 2).T
elif (md_var.shape[1] == 2):
pass
else:
err_msg = ("Received array of model discrepancy variances %r has "
"incorrect number of values (%i != 2)!" %
(name, md_var.shape[1]))
raise ShapeError(err_msg)
# Check if all values are non-negative floats
md_var = check_vals(md_var, 'md_var', 'nneg', 'float')
# Log again and return md_var
logger.info("Finished validating provided set of model discrepancy "
"variances %r." % (name))
return (md_var)
def _check_sam_set(self, sam_set, name):
"""
Checks validity of provided set of model parameter samples `sam_set` in
this :obj:`~ModelLink` instance.
Parameters
----------
sam_set : 1D or 2D array_like or dict
Parameter/sample set to validate in this :obj:`~ModelLink`
instance.
name : str
The name of the parameter/sample set, which is used in the error
message if the validation fails.
Returns
-------
sam_set : 1D or 2D :obj:`~numpy.ndarray` object
The provided `sam_set` if the validation was successful. If
`sam_set` was a dict, it will be converted to a
:obj:`~numpy.ndarray` object.
"""
# Make logger
logger = getCLogger('CHECK')
logger.info("Validating provided set of model parameter samples %r." %
(name))
# If sam_set is a dict, convert it to a NumPy array
if isinstance(sam_set, dict):
sam_set = np_array(sdict(sam_set).values()).T
# Make sure that sam_set is a NumPy array
sam_set = np_array(sam_set)
# Raise error if sam_set is not 1D or 2D
if not (sam_set.ndim == 1 or sam_set.ndim == 2):
err_msg = ("Input argument %r is not one-dimensional or "
"two-dimensional!" % (name))
raise_error(err_msg, ShapeError, logger)
# Raise error if sam_set does not have n_par parameter values
if not (sam_set.shape[-1] == self._n_par):
err_msg = ("Input argument %r has incorrect number of parameters "
"(%i != %i)!" % (name, sam_set.shape[-1], self._n_par))
raise_error(err_msg, ShapeError, logger)
# Check if sam_set solely consists out of floats
sam_set = check_vals(sam_set, name, 'float')
# Check if all samples are within parameter space
sam_set_2D = np_array(sam_set, ndmin=2)
rng = self._par_rng
check = np.apply_along_axis(
lambda x: ((rng[:, 0] <= x) * (x <= rng[:, 1])).all(), 1,
sam_set_2D)
# If check is not empty (can be indexed), raise error
try:
index = np.argwhere(~check)[0]
except IndexError:
pass
else:
err_msg = ("Input argument '%s%s' is outside parameter space!" %
(name, index if sam_set.ndim != 1 else ''))
raise_error(err_msg, ValueError, logger)
# Log again and return sam_set
logger.info("Finished validating provided set of model parameter "
"samples %r." % (name))
return (sam_set)
def convert_data(model_data):
"""
Converts the provided `model_data` into a full data dict, taking into
account all formatting options, and returns it.
This function can be used externally to check how the provided `model_data`
would be interpreted when provided to the
:class:`~prism.modellink.ModelLink` subclass. Its output can be used for
the 'model_data' input argument.
Parameters
----------
model_data : array_like, dict or str
Anything that can be converted to a dict that provides model data
information.
Returns
-------
data_dict : dict
Dict with the provided `model_data` converted to its full format.
"""
# If a data file is given
if isinstance(model_data, str):
# Obtain absolute path to given file
data_file = path.abspath(model_data)
# Read the data file in as a string
data_points = np.genfromtxt(data_file, dtype=(str), delimiter=':',
autostrip=True)
# Make sure that data_points is 2D
data_points = np_array(data_points, ndmin=2)
# Convert read-in data to dict
model_data = dict(data_points)
# If a data dict is given
elif isinstance(model_data, dict):
model_data = dict(model_data)
# If anything else is given
else:
# Check if it can be converted to a dict
try:
model_data = dict(model_data)
except Exception:
raise TypeError("Input model data cannot be converted to type "
"'dict'!")
# Make empty data_dict
data_dict = dict()
# Loop over all items in model_data
for key, value in model_data.items():
# Convert key to an actual data_idx
idx = e13.split_seq(key)
# Check if tmp_idx is not empty
if not idx:
raise e13.InputError("Model data contains a data point with no "
"identifier!")
# Convert value to an actual data point
data = e13.split_seq(value)
# Check if provided data value is valid
val = check_vals(data[0], 'data_val%s' % (idx), 'float')
# Extract data error and space
# If length is two, centered error and no data space were given
if(len(data) == 2):
err = [check_vals(data[1], 'data_err%s' % (idx), 'float', 'pos')]*2
spc = 'lin'
# If length is three, there are two possibilities
elif(len(data) == 3):
# If the third column contains a string, it is the data space
if isinstance(data[2], str):
err = [check_vals(data[1], 'data_err%s' % (idx),
'float', 'pos')]*2
spc = data[2]
# If the third column contains no string, it is error interval
else:
err = check_vals(data[1:3], 'data_err%s' % (idx),
'float', 'pos')
spc = 'lin'
# If length is four+, error interval and data space were given
else:
err = check_vals(data[1:3], 'data_err%s' % (idx), 'float', 'pos')
spc = data[3]
# Check if valid data space has been provided
spc = str(spc).replace("'", '').replace('"', '')
if spc.lower() in ('lin', 'linear'):
spc = 'lin'
elif spc.lower() in ('log', 'log10', 'log_10'):
spc = 'log10'
elif spc.lower() in ('ln', 'loge', 'log_e'):
spc = 'ln'
else:
raise ValueError("Input argument 'data_spc%s' is invalid (%r)!"
% (idx, spc))
# Save data identifier as tuple or single element
if(len(idx) == 1):
idx = idx[0]
else:
idx = tuple(idx)
# Add entire data point to data_dict
data_dict[idx] = [val, *err, spc]
# Return data_dict
return(data_dict)
def convert_parameters(model_parameters):
"""
Converts the provided `model_parameters` into a full parameters dict,
taking into account all formatting options, and returns it.
This function can be used externally to check how the provided
`model_parameters` would be interpreted when provided to the
:class:`~prism.modellink.ModelLink` subclass. Its output can be used for
the 'model_parameters' input argument.
Parameters
----------
model_parameters : array_like, dict or str
Anything that can be converted to a dict that provides model parameters
information.
Returns
-------
par_dict : dict
Dict with the provided `model_parameters` converted to its full format.
"""
# If a parameter file is given
if isinstance(model_parameters, str):
# Obtain absolute path to given file
par_file = path.abspath(model_parameters)
# Read the parameter file in as a string
pars = np.genfromtxt(par_file, dtype=(str), delimiter=':',
autostrip=True)
# Make sure that pars is 2D
pars = np_array(pars, ndmin=2)
# Convert read-in parameters to dict
model_parameters = sdict(pars)
# If a parameter dict is given
elif isinstance(model_parameters, dict):
model_parameters = sdict(model_parameters)
# If anything else is given
else:
# Check if it can be converted to a dict
try:
model_parameters = sdict(model_parameters)
except Exception:
raise TypeError("Input model parameters cannot be converted to"
" type 'dict'!")
# Initialize empty par_dict
par_dict = sdict()
# Loop over all items in model_parameters
for name, values_str in model_parameters.items():
# Convert values_str to values
values = e13.split_seq(values_str)
# Check if provided name is a string
name = check_vals(name, 'par_name[%r]' % (name), 'str')
# Check if provided range consists of two floats
par_rng = check_vals(values[:2], 'par_rng[%r]' % (name), 'float')
# Check if provided lower bound is lower than the upper bound
if(par_rng[0] >= par_rng[1]):
raise ValueError("Input argument 'par_rng[%r]' does not define a "
"valid parameter range (%f !< %f)!"
% (name, par_rng[0], par_rng[1]))
# Check if a float parameter estimate was provided
try:
est = check_vals(values[2], 'par_est[%r]' % (name), 'float')
# If no estimate was provided, save it as None
except IndexError:
est = None
# If no float was provided, check if it was None
except TypeError as error:
# If it is None, save it as such
if(str(values[2]).lower() == 'none'):
est = None
# If it is not None, reraise the previous error
else:
raise error
# If a float was provided, check if it is within parameter range
else:
if not(values[0] <= est <= values[1]):
raise ValueError("Input argument 'par_est[%r]' is outside "
"of defined parameter range!" % (name))
# Add parameter to par_dict
par_dict[name] = [*par_rng, est]
# Return par_dict
return(par_dict)
def get_walkers(pipeline_obj,
*,
emul_i=None,
init_walkers=None,
req_n_walkers=None,
unit_space=False,
lnpost_fn=None,
**kwargs):
"""
Analyzes proposed `init_walkers` and returns plausible `p0_walkers`.
Analyzes sample set `init_walkers` in the provided `pipeline_obj` at
iteration `emul_i` and returns all samples that are plausible to be used as
starting positions for MCMC walkers. The provided samples and returned
walkers should be/are given in unit space if `unit_space` is *True*.
If `init_walkers` is *None*, returns :attr:`~prism.Pipeline.impl_sam`
instead if it is available.
This function needs to be called by all MPI ranks.
Parameters
----------
pipeline_obj : :obj:`~prism.Pipeline` object
The instance of the :class:`~prism.Pipeline` class that needs to be
used for determining the plausibility of the proposed starting
positions.
Optional
--------
%(emul_i)s
init_walkers : 2D array_like, dict, int or None. Default: None
Sample set of proposed initial MCMC walker positions. All plausible
samples in `init_walkers` will be returned.
If int, generate an LHD of provided size and return all plausible
samples.
If *None*, return :attr:`~prism.Pipeline.impl_sam` corresponding to
iteration `emul_i` instead.
req_n_walkers : int or None. Default: None
The minimum required number of plausible starting positions that should
be returned. If *None*, all plausible starting positions in
`init_walkers` are returned instead.
.. versionadded:: 1.2.0
unit_space : bool. Default: False
Bool determining whether or not the provided samples and returned
walkers are given in unit space.
lnpost_fn : function or None. Default: None
If function, call :func:`~get_hybrid_lnpost_fn` using `lnpost_fn` and
the same values for `pipeline_obj`, `emul_i` and `unit_space`, and
return the resulting function definition `hybrid_lnpost()`. Any
additionally provided `kwargs` are also passed to it.
Returns
-------
n_walkers : int
Number of returned MCMC walkers. Note that this number can be higher
than `req_n_walkers` if not *None*.
p0_walkers : 2D :obj:`~numpy.ndarray` object or dict
Array containing plausible starting positions of valid MCMC walkers.
If `init_walkers` was provided as a dict, `p0_walkers` will be a dict.
hybrid_lnpost : function (if `lnpost_fn` is a function)
The function returned by :func:`~get_hybrid_lnpost_fn` using
`lnpost_fn`, `pipeline_obj`, `emul_i`, `unit_space` and `kwargs` as the
input values.
See also
--------
:func:`~get_hybrid_lnpost_fn`
Returns a function definition ``hybrid_lnpost(par_set, *args,
**kwargs)``.
:attr:`~prism.Pipeline.worker_mode`
Special context manager within which all code is executed in worker
mode.
Notes
-----
If `init_walkers` is *None* and emulator iteration `emul_i` has not been
analyzed yet, a :class:`~prism._internal.RequestError` will be raised.
If `req_n_walkers` is not *None*, a custom Metropolis-Hastings sampling
algorithm is used to generate the required number of starting positions.
All plausible samples in `init_walkers` are used as the start of every MCMC
chain. Note that if the number of plausible samples in `init_walkers` is
small, it is possible that the returned `p0_walkers` are not spread out
properly over parameter space.
"""
# Make abbreviation for pipeline_obj
pipe = pipeline_obj
# Check if provided pipeline_obj is an instance of the Pipeline class
if not isinstance(pipe, Pipeline):
raise TypeError("Input argument 'pipeline_obj' must be an instance of "
"the Pipeline class!")
# Check if the provided pipeline_obj uses a default emulator
if (pipe._emulator._emul_type != 'default'):
raise e13.InputError("Input argument 'pipeline_obj' does not use a "
"default emulator!")
# Get emulator iteration
emul_i = pipe._emulator._get_emul_i(emul_i)
# If req_n_walkers is not None, check if it is an integer
if req_n_walkers is not None:
req_n_walkers = check_vals(req_n_walkers, 'req_n_walkers', 'int',
'pos')
# Check if unit_space is a bool
unit_space = check_vals(unit_space, 'unit_space', 'bool')
# Assume that walkers are not to be returned as a dict
walker_dict = False
# Check if lnpost_fn is None and try to get hybrid_lnpost function if not
if lnpost_fn is not None:
try:
hybrid_lnpost =\
get_hybrid_lnpost_fn(lnpost_fn, pipe, emul_i=emul_i,
unit_space=unit_space, **kwargs)
except e13.InputError:
raise e13.InputError("Input argument 'lnpost_fn' is invalid!")
# If init_walkers is None, use impl_sam of emul_i
if init_walkers is None:
# Controller checking if emul_i has already been analyzed
if pipe._is_controller:
# If iteration has not been analyzed, raise error
if not pipe._n_eval_sam[emul_i]:
raise RequestError("Emulator iteration %i has not been "
"analyzed yet!" % (emul_i))
# If iteration is last iteration, init_walkers is current impl_sam
elif (emul_i == pipe._emulator._emul_i):
init_walkers = pipe._impl_sam
# If iteration is not last, init_walkers is previous impl_sam
else:
init_walkers = pipe._emulator._sam_set[emul_i + 1]
# Make sure to make a copy of init_walkers to avoid modifications
init_walkers = init_walkers.copy()
# Broadcast init_walkers to workers as p0_walkers
p0_walkers = pipe._comm.bcast(init_walkers, 0)
# If init_walkers is not None, use provided samples or LHD size
else:
# Controller checking if init_walkers is valid
if pipe._is_controller:
# If init_walkers is an int, create LHD of provided size
if isinstance(init_walkers, int):
# Check if provided integer is positive
n_sam = check_vals(init_walkers, 'init_walkers', 'pos')
# Obtain the par_space to sample in
par_space = pipe._get_impl_space(emul_i)
# If par_space is None, use the corresponding emul_space
if par_space is None:
par_space = pipe._emulator._emul_space[emul_i]
# Create LHD of provided size
init_walkers = e13.lhd(n_sam, pipe._modellink._n_par,
par_space, 'center', pipe._criterion,
100)
# If init_walkers is not an int, it must be array_like or dict
else:
# If init_walkers is provided as a dict, convert it
if isinstance(init_walkers, dict):
# Make sure that init_walkers is a SortedDict
init_walkers = sdict(init_walkers)
# Convert it to normal
init_walkers = np_array(init_walkers.values()).T
# Return p0_walkers as a dict
walker_dict = True
# Make sure that init_walkers is a NumPy array
init_walkers = np_array(init_walkers, ndmin=2)
# If unit_space is True, convert init_walkers to par_space
if unit_space:
init_walkers = pipe._modellink._to_par_space(init_walkers)
# Check if init_walkers is valid
init_walkers = pipe._modellink._check_sam_set(
init_walkers, 'init_walkers')
# Broadcast init_walkers to workers
init_walkers = pipe._comm.bcast(init_walkers, 0)
# Analyze init_walkers and save them as p0_walkers
p0_walkers = pipe._evaluate_sam_set(emul_i, init_walkers, 'analyze')
# Check if init_walkers is not empty and raise error if it is
if not p0_walkers.shape[0]:
raise e13.InputError("Input argument 'init_walkers' contains no "
"plausible samples!")
# If req_n_walkers is not None, use MH MCMC to find all required walkers
if req_n_walkers is not None:
n_walkers, p0_walkers = _do_mh_walkers(pipe, p0_walkers, req_n_walkers)
else:
p0_walkers = np.unique(p0_walkers, axis=0)
n_walkers = p0_walkers.shape[0]
# Check if p0_walkers needs to be converted
if unit_space:
p0_walkers = pipe._modellink._to_unit_space(p0_walkers)
# Check if p0_walkers needs to be returned as a dict
if walker_dict:
p0_walkers = pipe._modellink._get_sam_dict(p0_walkers)
# Check if hybrid_lnpost was requested and return it as well if so
if lnpost_fn is not None:
return (n_walkers, p0_walkers, hybrid_lnpost)
else:
return (n_walkers, p0_walkers)
def hybrid_lnpost(par_set, *args, **kwargs):
"""
Calculates the natural logarithm of the posterior probability of
`par_set` using the provided function `lnpost_fn`, in addition to
constraining it first with the emulator defined in the `pipeline_obj`.
This function needs to be called by all MPI ranks unless called within
the :attr:`~prism.Pipeline.worker_mode` context manager.
Parameters
----------
par_set : 1D array_like or dict
Sample to calculate the posterior probability for. This sample is
first analyzed in `pipeline_obj` and only given to `lnpost_fn` if
it is plausible. If `par_dict` is *True*, this is a dict.
args : positional arguments
Positional arguments that need to be passed to `lnpost_fn`.
kwargs : keyword arguments
Keyword arguments that need to be passed to `lnpost_fn`.
Returns
-------
lnp : float
The natural logarithm of the posterior probability of `par_set`, as
determined by `lnpost_fn` if `par_set` is plausible. If
`impl_prior` is *True*, `lnp` is calculated as `lnprior` +
`lnpost_fn()`, with `lnprior` the natural logarithm of the first
implausibility cut-off value of `par_set` scaled with its maximum.
"""
# If par_dict is True, convert par_set to a NumPy array
if par_dict:
sam = np_array(sdict(par_set).values(), ndmin=2)
else:
sam = np_array(par_set, ndmin=2)
# If unit_space is True, convert par_set to par_space
if unit_space:
sam = pipe._modellink._to_par_space(sam)
# Check if par_set is within parameter space and return -inf if not
par_rng = pipe._modellink._par_rng
if not ((par_rng[:, 0] <= sam[0]) * (sam[0] <= par_rng[:, 1])).all():
return (-np.infty)
# Check what sampling is requested and analyze par_set
if impl_prior:
impl_sam, lnprior = pipe._make_call('_evaluate_sam_set', emul_i,
sam, 'hybrid')
else:
impl_sam = pipe._make_call('_evaluate_sam_set', emul_i, sam,
'analyze')
lnprior = 0
# If par_set is plausible, call lnpost_fn
if len(impl_sam):
return (lnprior + lnpost_fn(par_set, *args, **kwargs))
# If par_set is not plausible, return -inf
else:
return (-np.infty)
def test_np_array():
array = np.array([1, 2])
assert np_array(array) is array
