""" Abstract parameter subspace :math:`\mathbb{R}^{d}`. """
from xpsi.global_imports import *
from xpsi.utils import make_verbose
from abc import ABCMeta
from xpsi.Parameter import Parameter
[docs]class ParameterSubspace(object, metaclass=ABCMeta):
""" Ordered parameter subspace.
:param str prefix:
In common modelling patterns there are multiple instances
of a particular subspace, so provide a unique naming prefix. The prefix
will be suffixed with a double-underscore. Note that this prefix will
prepend prefixes for encapsulated parameters lower in the hierarchy
which themselves have identification prefixes.
:param args:
Instances of :class:`~.Parameter.Parameter`, or iterables over
instances of :class:`~.Parameter.Parameter` or
:class:`~.ParameterSubspace.ParameterSubspace`. All parameters
and subspaces will be merged into this new subspace.
"""
@make_verbose()
def __init__(self, *args, **kwargs):
prefix = kwargs.get('prefix', None)
if prefix is not None:
self.prefix = prefix
if not args:
yield 'No parameters supplied... empty subspace created.'
self._params = []
self.merge(*args)
yield
[docs] def merge(self, *args):
""" Merge parameters into the subspace, thereby expanding it. """
for obj in args: # siphon off the parameters for merge
if isinstance(obj, Parameter):
self._handle(obj)
elif obj is not None: # some arguments will default to ``None``
try:
iter(obj)
except TypeError:
print('Argument must be a parameter or an iterable of '
'parameters or subspaces.')
raise
else:
if isinstance(obj, ParameterSubspace):
self._handle_prefix(obj)
for o in obj:
if isinstance(o, Parameter):
self._handle(o)
elif isinstance(o, ParameterSubspace):
self._handle_prefix(o)
for param in o:
self._handle(param)
def _handle(self, param):
""" Check for duplicates and grow in dimensionality if not. """
try:
if len(self._params) >= 1:
for i in range(1, len(self._params) + 1):
temp = self._params[len(self._params) - i]
if param is temp:
return None # quietly do nothing
elif param.name == temp.name:
raise ValueError('Duplicated parameter name '
'%s.' % param.name)
except AttributeError:
pass
try:
self._params.append(param)
except AttributeError:
self._params = [param]
try:
if param.permit_prepend: # check permissions
self._prepend(param)
except AttributeError:
pass # quietly do nothing
def _handle_prefix(self, subspace):
try:
self.prefix
except AttributeError:
pass # quietly do nothing
else:
try:
subspace.prefix
except AttributeError:
subspace.prefix = self.prefix
else:
if self.prefix not in subspace.prefix:
subspace.prefix = self.prefix + '__' + subspace.prefix
@property
def params(self):
""" Get the list of parameter objects. """
return self._params
[docs] def get_param(self, name):
""" Get a reference to a parameter object by name. """
if isinstance(name, _six.string_types):
for param in self._params:
if name == param.name:
return param
try:
if self.prefix + '__' not in name:
name = self.prefix + '__' + name
except AttributeError:
pass
else:
for param in self._params:
if name == param.name:
return param
raise KeyError('No parameter called \"'+ name +'\" in subspace with matching name.')
[docs] def index(self, name):
""" Get the index of a free parameter. """
for i, param in enumerate(self):
if name == param.name:
return i
try:
self.prefix
except AttributeError:
continue # with iteration
else:
if self.prefix + '__' not in name: # safety guard for prefix
if self.prefix + '__' + name == param.name:
return i
def __len__(self):
""" Get the number of free parameters in the subspace. """
return sum(1 for _ in self)
[docs] def __str__(self):
""" Get a summary of the parameters constituting the subspace. """
summary = 'Free parameters\n'
summary += '---------------\n'
for param in self:
summary += param.name + ': ' + str(param) + '\n'
derived = ''
for param in self._params:
if param.fixed:
derived += param.name + ': ' + str(param) + '\n'
if derived:
summary += '\nDerived/fixed parameters\n'
summary += '------------------------\n'
summary += derived
return summary
[docs] def __repr__(self):
""" Redirect to the string representation. """
return str(self)
@property
def names(self):
""" Get a list of parameter names. """
return [param.name for param in self._params]
@property
def vector(self):
""" Get all variable values (free parameters and fixed/derived). """
return [p.evaluate(self) for p in self._params]
[docs] def __getitem__(self, key):
""" Pass a string or an integer (latter only for free parameters). """
if isinstance(key, _six.string_types):
return self.get_param(key).evaluate(self) # "caller" is subspace
elif isinstance(key, int):
try: # note only free parameters considered for this variant
return [param for param in self][key].evaluate(self)
except IndexError:
raise
[docs] def __setitem__(self, key, value):
""" Pass a string or an integer (latter only for free parameters). """
if isinstance(key, _six.string_types):
try:
if self.prefix + '__' not in key:
key = self.prefix + '__' + key
except AttributeError:
pass
for param in self._params:
if key == param.name:
param.value = value
del value
break
try:
value
except NameError:
pass
else:
raise KeyError('No parameter called \"'+ key +'\" in subspace with matching name.')
elif isinstance(key, int):
try: # note only free parameters considered for this variant
[param for param in self][key].value = value
except IndexError:
print('Invalid index to parameter subspace.')
raise
[docs] def __iter__(self):
""" Get an iterator over *free* parameters. """
self._index = -1
return self
#def __next__(self):
# """ Redirect for Python 3 compatibility. """
# return self.next()
[docs] def __next__(self):
""" Get next free parameter. """
self._index += 1
if self._index == len(self._params):
raise StopIteration
elif self._params[self._index].fixed:
return next(self)
else:
return self._params[self._index]
[docs] def __call__(self, p = None):
""" Useful callable way to update parameters with a simple vector.
The order must match the order in which parameters were merged into
the subspace. Note that this method is often overwritten in subclasses,
but this parent method can always be accessed if required.
:param array-like p:
New point to update to. If ``None``, the current point is returned.
The object must be ordered to match that of container ``self``.
:returns: Current point (if the call was not an update).
:rtype: array-like
"""
if p is not None:
if len(p) != len(self):
raise ValueError('Parameter vector length mismatch.')
for param, value in zip(self, p):
param(value)
else:
return [param() for param in self]
@property
def needs_update(self):
""" Do cached dependencies need to be updated? """
for param in self.params:
if param.needs_update:
return True
return False
@property
def cached(self):
""" Get the cached values of all free parameters in the subspace. """
return [param.cached for param in self]
[docs] def clear_cache(self):
""" Clear the cache for all free parameters in the subspace.
.. note::
That this also deletes the current parameter values, in
addition to the cached previous values.
"""
for param in self:
del param.cached
param.value = param.cached
def _prepend(self, param):
if self.prefix + '__' not in param.name:
param.name = self.prefix + '__' + param.name
@property
def prefix(self):
""" Get the unique prefix for subspace identification. """
return self._prefix
@prefix.setter
def prefix(self, prefix):
if isinstance(prefix, _six.string_types):
self._prefix = prefix
else:
raise ValueError('Invalid type for prefix string.')
[docs] @classmethod
def _update_doc(cls):
""" Append the docstring with parameter names in class attributes. """
try:
cls.required_names
except AttributeError:
pass
else:
cls.__doc__ += '\n Required parameter names:'
for name in cls.required_names:
cls.__doc__ += '\n * ' + name
cls.__doc__ += '\n'
try:
cls.optional_names
except AttributeError:
pass
else:
cls.__doc__ += '\n Optional parameter names:'
for name in cls.optional_names:
cls.__doc__ += '\n * ' + name
cls.__doc__ += '\n'