def __mul__(self, right):
""" A true multiplication of two potentials would be defined as X * Y = Z where the sets of variables z = x U y. We would then identify the instantiations of x and y that are consistent with z and Z(z) = X(x)Y(y). We are generally going to be multiplying sepset potentials by clique potentials where the variables of a setpset potential are a subset of the variables of the clique. Therefore we are going to assume in this operation that right's variables are a subset of self's.
"""
# right should only be a DiscreteDistribution or a ContinuousDistribution if it is a subset and it should be __imul__
assert(not isinstance(right, DiscreteDistribution) and not isinstance(right, ConditionalDiscreteDistribution)), \
"Attempt to Multiply Potential with incompatible type: Discrete or Conditional"
if isinstance(right, (int, float, complex, long)):
potential = copy.deepcopy(self)
potential.table *= right
else:
nodeSet = self.__nodeSet_.union(right.__nodeSet_)
potential = Potential(list(nodeSet))
selfValues = [potential.nodes.index(node) for node in self.nodes]
rightValues = [potential.nodes.index(node) for node in right.nodes]
# Store the following lists so we don't have to recompute them on every iteration
potAxes = range(potential.nDims)
selfAxes = range(self.nDims)
rightAxes = range(right.nDims)
#OPTIMIZE: Should be able to do this without blindly iterating through dimensions.
for seq in Utilities.sequence_generator(potential.dims):
#OPTIMIZE: Could access the table directly, but would break down our abstraction
potIndex = potential.generate_index(seq, potAxes)
selfIndex = self.generate_index(seq[selfValues], selfAxes)
rightIndex = right.generate_index(seq[rightValues], rightAxes)
potential[potIndex] = self[selfIndex] * right[rightIndex]
return potential
def __mul__(self, right):
""" A true multiplication of two potentials would be defined as X * Y = Z where the sets of variables z = x U y. We would then identify the instantiations of x and y that are consistent with z and Z(z) = X(x)Y(y). We are generally going to be multiplying sepset potentials by clique potentials where the variables of a setpset potential are a subset of the variables of the clique. Therefore we are going to assume in this operation that right's variables are a subset of self's.
"""
# right should only be a DiscreteDistribution or a ContinuousDistribution if it is a subset and it should be __imul__
assert(not isinstance(right, DiscreteDistribution) and not isinstance(right, ConditionalDiscreteDistribution)), \
"Attempt to Multiply Potential with incompatible type: Discrete or Conditional"
if isinstance(right, (int, float, complex, long)):
potential = copy.deepcopy(self)
potential.table *= right
else:
nodeSet = self.__nodeSet_.union(right.__nodeSet_)
potential = Potential(list(nodeSet))
selfValues = [potential.nodes.index(node) for node in self.nodes]
rightValues = [potential.nodes.index(node) for node in right.nodes]
# Store the following lists so we don't have to recompute them on every iteration
potAxes = range(potential.nDims)
selfAxes = range(self.nDims)
rightAxes = range(right.nDims)
#OPTIMIZE: Should be able to do this without blindly iterating through dimensions.
for seq in Utilities.sequence_generator(potential.dims):
#OPTIMIZE: Could access the table directly, but would break down our abstraction
potIndex = potential.generate_index(seq, potAxes)
selfIndex = self.generate_index(seq[selfValues], selfAxes)
rightIndex = right.generate_index(seq[rightValues], rightAxes)
potential[potIndex] = self[selfIndex] * right[rightIndex]
return potential
def marginalize(self, other):
""" Return a new potential that is the marginalization of this potential given other. This identifies the instantiations of self (s1,s2,...,sn) that are consistent with other and sum self(s1) + self(s2) + ... + self(sn).
"""
new = copy.deepcopy(other)
intersect = self.__nodeSet_.intersection(new.__nodeSet_)
newAxes = range(new.nDims)
sequence = Utilities.sequence_generator(other.dims)
for seq in sequence:
index = self.generate_index_node(seq, intersect)
newIndex = new.generate_index(seq, newAxes)
val = self[index]
if isinstance(val, ndarray):
val = val.sum()
new[newIndex] = val
return new
def marginalize(self, other):
""" Return a new potential that is the marginalization of this potential given other. This identifies the instantiations of self (s1,s2,...,sn) that are consistent with other and sum self(s1) + self(s2) + ... + self(sn).
"""
new = copy.deepcopy(other)
intersect = self.__nodeSet_.intersection(new.__nodeSet_)
newAxes = range(new.nDims)
sequence = Utilities.sequence_generator(other.dims)
for seq in sequence:
index = self.generate_index_node(seq, intersect)
newIndex = new.generate_index(seq, newAxes)
val = self[index]
if isinstance(val, ndarray):
val = val.sum()
new[newIndex] = val
return new
def __imul__(self, right):
""" This is the same operation as __mul__ except that if right.nodes is a subset of self.nodes, we do the multiplication in place, because there is no reason to make a copy, which wastes time and space.
"""
if isinstance(right, (int, float, complex, long)):
self.table *= right
# FIXME: should be right.__nodeSet_ but doesn't work when right is DiscreteDistribution
elif self.__nodeSet_.issuperset(right.nodes):
#OPTIMIZE: There must be a way to do this without iterating over every value of table
selfAxes = [self.nodes.index(node) for node in right.nodes]
rightAxes = range(right.nDims)
for seq in Utilities.sequence_generator(right.dims):
selfIndex = self.generate_index(seq, selfAxes)
#OPTIMIZE: Could index right.table directly, but this upholds our abstraction barrier
rightIndex = right.generate_index(seq, rightAxes)
self[selfIndex] *= right[rightIndex]
else:
""" If potential will be over a different set of variables after multiplication, might as well use full __mul__ version, which copies.
"""
self = self.__mul__(right)
return self
def __imul__(self, right):
""" This is the same operation as __mul__ except that if right.nodes is a subset of self.nodes, we do the multiplication in place, because there is no reason to make a copy, which wastes time and space.
"""
if isinstance(right, (int, float, complex, long)):
self.table *= right
# FIXME: should be right.__nodeSet_ but doesn't work when right is DiscreteDistribution
elif self.__nodeSet_.issuperset(right.nodes):
#OPTIMIZE: There must be a way to do this without iterating over every value of table
selfAxes = [self.nodes.index(node) for node in right.nodes]
rightAxes = range(right.nDims)
for seq in Utilities.sequence_generator(right.dims):
selfIndex = self.generate_index(seq, selfAxes)
#OPTIMIZE: Could index right.table directly, but this upholds our abstraction barrier
rightIndex = right.generate_index(seq, rightAxes)
self[selfIndex] *= right[rightIndex]
else:
""" If potential will be over a different set of variables after multiplication, might as well use full __mul__ version, which copies.
"""
self = self.__mul__(right)
return self
