def sample_hising(self, h, J, **kwargs):
"""Sample from a higher-order Ising model.
Convert the given higher-order Ising model to a :obj:`.BinaryPolynomial`
and call :meth:`.sample_poly`.
Args:
h (dict):
Variable biases of the Ising problem as a dict of
the form `{v: bias, ...}`, where `v` is a variable in the
polynomial and `bias` its associated coefficient.
J (dict):
Interaction biases of the Ising problem as a dict of
the form `{(u, v, ...): bias}`, where `u`, `v`, are spin-valued
variables in the polynomial and `bias` their associated
coefficient.
**kwargs:
See :meth:`.sample_poly` for additional keyword definitions.
Returns:
:obj:`.SampleSet`
See also:
:meth:`.sample_poly`, :meth:`.sample_hubo`
"""
return self.sample_poly(BinaryPolynomial.from_hising(h, J), **kwargs)
def sample_ising(self, h, J, offset=0, scalar=None,
bias_range=1, quadratic_range=None,
ignored_variables=None, ignored_interactions=None,
ignore_offset=False, **parameters):
""" Scale and sample from the problem provided by h, J, offset
if scalar is not given, problem is scaled based on bias and quadratic
ranges.
Args:
h (dict): linear biases
J (dict): quadratic or higher order biases
offset (float, optional): constant energy offset
scalar (number):
Value by which to scale the energy range of the binary quadratic model.
bias_range (number/pair):
Value/range by which to normalize the all the biases, or if
`quadratic_range` is provided, just the linear biases.
quadratic_range (number/pair):
Value/range by which to normalize the quadratic biases.
ignored_variables (iterable, optional):
Biases associated with these variables are not scaled.
ignored_interactions (iterable[tuple], optional):
As an iterable of 2-tuples. Biases associated with these interactions are not scaled.
ignore_offset (bool, default=False):
If True, the offset is not scaled.
**parameters:
Parameters for the sampling method, specified by the child sampler.
Returns:
:obj:`dimod.SampleSet`
"""
if any(len(inter) > 2 for inter in J):
# handle HUBO
import warnings
msg = ("Support for higher order Ising models in ScaleComposite is "
"deprecated and will be removed in dimod 0.9.0. Please use "
"PolyScaleComposite.sample_hising instead.")
warnings.warn(msg, DeprecationWarning)
from dimod.reference.composites.higherordercomposites import PolyScaleComposite
from dimod.higherorder.polynomial import BinaryPolynomial
poly = BinaryPolynomial.from_hising(h, J, offset=offset)
ignored_terms = set()
if ignored_variables is not None:
ignored_terms.update(frozenset(v) for v in ignored_variables)
if ignored_interactions is not None:
ignored_terms.update(frozenset(inter) for inter in ignored_interactions)
if ignore_offset:
ignored_terms.add(frozenset())
return PolyScaleComposite(self.child).sample_poly(poly, scalar=scalar,
bias_range=bias_range,
poly_range=quadratic_range,
ignored_terms=ignored_terms,
**parameters)
bqm = BinaryQuadraticModel.from_ising(h, J, offset=offset)
return self.sample(bqm, scalar=scalar,
bias_range=bias_range,
quadratic_range=quadratic_range,
ignored_variables=ignored_variables,
ignored_interactions=ignored_interactions,
ignore_offset=ignore_offset, **parameters)