def andGetResult(self):
if self._dist is None:
raise Exception("No distribution specified for parameter '%s'" %
self._name)
# if there is no transformation defined, use the
# linear transformation as standard
if self.__trans is None:
bounds = self._dist.getBounds()
if self._dist.getDim() == 1:
self.__trans = LinearTransformation(bounds[0], bounds[1])
else:
self.__trans = JointTransformation()
for i in range(self._dist.getDim()):
a, b = bounds[i]
self.__trans.add(LinearTransformation(a, b))
# check if there are enough identifiers given
if self._dist.getDim() > 1 and self._dist.getDim() != len(self._name):
raise AttributeError(
"not enough names provided; given %i (%s), expected %i" %
(len(self._name), ", ".join(self._name), self._dist.getDim()))
# check if there is and SGDE involved that need this
# transformation
if isinstance(self._dist, SGDEdist):
self._dist.transformation = self.__trans
# check wiener askey scheme
partOfWienerAskeyScheme = False
orthogPolyConfig = OrthogonalPolynomialBasis1DConfiguration()
if isinstance(self.__trans, RosenblattTransformation) or \
isinstance(self._dist, Uniform):
orthogPolyConfig.polyParameters.type_ = OrthogonalPolynomialBasisType_LEGENDRE
orthogPolyConfig.polyParameters.lowerBound_ = self._dist.getBounds(
)[0]
orthogPolyConfig.polyParameters.upperBound_ = self._dist.getBounds(
)[1]
orthogPoly = OrthogonalPolynomialBasis1D(orthogPolyConfig)
elif isinstance(self._dist, Normal):
orthogPolyConfig.polyParameters.type_ = OrthogonalPolynomialBasisType_HERMITE
orthogPoly = OrthogonalPolynomialBasis1D(orthogPolyConfig)
elif isinstance(self._dist, Beta):
orthogPolyConfig.polyParameters.type_ = OrthogonalPolynomialBasisType_JACOBI
orthogPolyConfig.polyParameters.alpha_ = self._dist.alpha()
orthogPolyConfig.polyParameters.beta_ = self._dist.beta()
orthogPoly = OrthogonalPolynomialBasis1D(orthogPolyConfig)
elif isinstance(self._dist, TLognormal):
orthogPolyConfig.polyParameters.type_ = OrthogonalPolynomialBasisType_BOUNDED_LOGNORMAL
orthogPolyConfig.polyParameters.logmean_ = np.log(self._dist.mu)
orthogPolyConfig.polyParameters.stddev_ = self._dist.sigma
orthogPolyConfig.polyParameters.lowerBound_ = self._dist.getBounds(
)[0]
orthogPolyConfig.polyParameters.upperBound_ = self._dist.getBounds(
)[1]
orthogPoly = OrthogonalPolynomialBasis1D(orthogPolyConfig)
else:
orthogPoly = None
return UncertainParameter(self._name, self._dist, self.__trans,
self._value, orthogPoly)
def andGetResult(self):
if self._dist is None:
raise Exception("No distribution specified for parameter '%s'" %
self._name)
# if there is no transformation defined, use the
# linear transformation as standard
if self.__trans is None:
bounds = self._dist.getBounds()
if self._dist.getDim() == 1:
self.__trans = LinearTransformation(bounds[0], bounds[1])
else:
self.__trans = JointTransformation()
for i in xrange(self._dist.getDim()):
a, b = bounds[i]
self.__trans.add(LinearTransformation(a, b))
# check if there are enough identifiers given
if self._dist.getDim() > 1 and self._dist.getDim() != len(self._name):
raise AttributeError(
"not enough names provided; given %i (%s), expected %i" %
(len(self._name), ", ".join(self._name), self._dist.getDim()))
# check if there is and SGDE involved that need this
# transformation
if isinstance(self._dist, SGDEdist):
self._dist.transformation = self.__trans
return UncertainParameter(self._name, self._dist, self.__trans,
self._value)
def withLinearTransformation(self):
if self._dist is not None:
a, b = self._dist.getBounds()
self.__trans = LinearTransformation(a, b)
else:
raise AttributeError('the distribution of "%s" is not specified \
yet but it is needed to know to apply the \
LinearTransformation' % self.__name)
return self
def __init__(self, mu, sigma, a, b):
"""
Constructor
@param mu: expectation value
@param sigma: standard deviation
@param a: lower boundary
@param b: upper boundary
"""
super(Normal, self).__init__()
self.__mu = float(mu)
self.__sigma = float(sigma)
self.__a, self.__b = a, b
# standard normal
self._dist = norm(loc=mu, scale=sigma)
self.__linearTrans = LinearTransformation(self._dist.cdf(self.__a),
self._dist.cdf(self.__b))
def marginalize(self):
"""
NOTE: just returns the marginalized active subset of params
"""
# marginalize the distribution
margDistList = []
margTransformations = []
activeParams = self.activeParams()
distributions = activeParams.getIndependentJointDistribution(
).getDistributions()
transformations = activeParams.getJointTransformation(
).getTransformations()
if len(distributions) == len(activeParams):
return self
else:
for dist, trans in zip(distributions, transformations):
# check if current parameter is independent
if dist.getDim() == 1:
margDistList.append(dist)
margTransformations.append(trans)
else:
# marginalize the densities and update the transformations
innertrans = trans.getTransformations()
for idim in range(dist.getDim()):
margDist = dist.marginalizeToDimX(idim)
margDistList.append(margDist)
# update transformations
if isinstance(innertrans[idim],
RosenblattTransformation):
margTransformations.append(
RosenblattTransformation(margDist))
else:
a, b = margDist.getBounds()
margTransformations.append(
LinearTransformation(a, b))
assert len(margDistList) == len(
margTransformations) == activeParams.getDim()
# update the parameter setting
from pysgpp.extensions.datadriven.uq.parameters.ParameterBuilder import ParameterBuilder
builder = ParameterBuilder()
up = builder.defineUncertainParameters()
for name, dist, trans in zip(activeParams.getNames(), margDistList,
margTransformations):
up.new().isCalled(name).withDistribution(dist)\
.withTransformation(trans)
return builder.andGetResult()
def testMarginalEstimationStrategy(self):
xlim = np.array([[-1, 1], [-1, 1]])
trans = JointTransformation()
dists = []
for idim in range(xlim.shape[0]):
trans.add(LinearTransformation(xlim[idim, 0], xlim[idim, 1]))
dists.append(Uniform(xlim[idim, 0], xlim[idim, 1]))
dist = J(dists)
def f(x):
return np.prod([(1 + xi) * (1 - xi) for xi in x])
def F(x):
return 1. - x**3 / 3.
grid, alpha_vec = interpolate(f,
1,
2,
gridType=GridType_Poly,
deg=2,
trans=trans)
alpha = alpha_vec.array()
q = (F(1) - F(-1))**2
q1 = doQuadrature(grid, alpha)
q2 = AnalyticEstimationStrategy().mean(grid, alpha, dist,
trans)["value"]
self.assertTrue(abs(q - q1) < 1e-10)
self.assertTrue(abs(q - q2) < 1e-10)
ngrid, nalpha, _ = MarginalAnalyticEstimationStrategy().mean(
grid, alpha, dist, trans, [[0]])
self.assertTrue(abs(nalpha[0] - 2. / 3.) < 1e-10)
plotSG3d(grid, alpha)
plt.figure()
plotSG1d(ngrid, nalpha)
plt.show()
def andGetResult(self):
trans = LinearTransformation(self._value, self._value)
return DeterministicParameter(self._name, self._value, trans)
def computeBF(grid, U, admissibleSet):
"""
Compute bilinear form
(A)_ij = \int phi_i phi_j dU(x)
on measure U, which is in this case supposed to be a lebesgue measure.
@param grid: Grid, sparse grid
@param U: list of distributions, Lebeasgue measure
@param admissibleSet: AdmissibleSet
@return: DataMatrix
"""
gs = grid.getStorage()
basis = getBasis(grid)
# interpolate phi_i phi_j on sparse grid with piecewise polynomial SG
# the product of two piecewise linear functions is a piecewise
# polynomial one of degree 2.
ngrid = Grid.createPolyBoundaryGrid(1, 2)
ngrid.getGenerator().regular(2)
ngs = ngrid.getStorage()
nodalValues = DataVector(ngs.size())
A = DataMatrix(admissibleSet.getSize(), gs.size())
b = DataVector(admissibleSet.getSize())
s = np.ndarray(gs.getDimension(), dtype='float')
# # pre compute basis evaluations
# basis_eval = {}
# for li in xrange(1, gs.getMaxLevel() + 1):
# for i in xrange(1, 2 ** li + 1, 2):
# # add value with it self
# x = 2 ** -li * i
# basis_eval[(li, i, li, i, x)] = basis.eval(li, i, x) * \
# basis.eval(li, i, x)
#
# # left side
# x = 2 ** -(li + 1) * (2 * i - 1)
# basis_eval[(li, i, li, i, x)] = basis.eval(li, i, x) * \
# basis.eval(li, i, x)
# # right side
# x = 2 ** -(li + 1) * (2 * i + 1)
# basis_eval[(li, i, li, i, x)] = basis.eval(li, i, x) * \
# basis.eval(li, i, x)
#
# # add values for hierarchical lower nodes
# for lj in xrange(li + 1, gs.getMaxLevel() + 1):
# a = 2 ** (lj - li)
# j = a * i - a + 1
# while j < a * i + a:
# # center
# x = 2 ** -lj * j
# basis_eval[(li, i, lj, j, x)] = basis.eval(li, i, x) * \
# basis.eval(lj, j, x)
# basis_eval[(lj, j, li, i, x)] = basis_eval[(li, i, lj, j, x)]
# # left side
# x = 2 ** -(lj + 1) * (2 * j - 1)
# basis_eval[(li, i, lj, j, x)] = basis.eval(li, i, x) * \
# basis.eval(lj, j, x)
# basis_eval[(lj, j, li, i, x)] = basis_eval[(li, i, lj, j, x)]
# # right side
# x = 2 ** -(lj + 1) * (2 * j + 1)
# basis_eval[(li, i, lj, j, x)] = basis.eval(li, i, x) * \
# basis.eval(lj, j, x)
# basis_eval[(lj, j, li, i, x)] = basis_eval[(li, i, lj, j, x)]
# j += 2
#
# print len(basis_eval)
# run over all rows
for i, gpi in enumerate(admissibleSet.values()):
# run over all columns
for j in range(gs.size()):
# print "%i/%i" % (i * gs.size() + j + 1, gs.size() ** 2)
gpj = gs.getPoint(j)
for d in range(gs.getDimension()):
# get level index
lid, iid = gpi.getLevel(d), gpi.getIndex(d)
ljd, ijd = gpj.getLevel(d), gpj.getIndex(d)
# compute left and right boundary of the support of both
# basis functions
lb = max([(iid - 1) * 2 ** -lid, (ijd - 1) * 2 ** -ljd])
ub = min([(iid + 1) * 2 ** -lid, (ijd + 1) * 2 ** -ljd])
# same level, different index
if lid == ljd and iid != ijd:
s[d] = 0.
# the support does not overlap
elif lid != ljd and lb >= ub:
s[d] = 0.
else:
# ----------------------------------------------------
# do the 1d interpolation ...
# define transformation function
T = LinearTransformation(lb, ub)
for k in range(ngs.size()):
x = ngs.getCoordinate(ngs.getPoint(k), 0)
x = T.unitToProbabilistic(x)
nodalValues[k] = basis.eval(lid, iid, x) * \
basis.eval(ljd, ijd, x)
# ... by hierarchization
v = hierarchize(ngrid, nodalValues)
# discretize the following function
def f(x, y):
xp = T.unitToProbabilistic(x)
return float(y * U[d].pdf(xp))
# sparse grid quadrature
g, w, _ = discretize(ngrid, v, f, refnums=0, level=5,
useDiscreteL2Error=False)
s[d] = doQuadrature(g, w) * (ub - lb)
# fig = plt.figure()
# plotSG1d(ngrid, v)
# x = np.linspace(xlow, ub, 100)
# plt.plot(np.linspace(0, 1, 100), U[d].pdf(x))
# fig.show()
# fig = plt.figure()
# plotSG1d(g, w)
# x = np.linspace(0, 1, 100)
# plt.plot(x,
# [evalSGFunction(ngrid, v, DataVector([xi])) * U[d].pdf(T.unitToProbabilistic(xi)) for xi in x])
# fig.show()
# plt.show()
# compute the integral of it
# ----------------------------------------------------
A.set(i, j, float(np.prod(s)))
if gs.getSequenceNumber(gpi) == j:
b[i] = A.get(i, j)
return A, b
class Normal(Dist):
"""
Represents a truncated normal distribution
See: http://en.wikipedia.org/wiki/Truncated_normal_distribution
"""
def __init__(self, mu, sigma, a, b):
"""
Constructor
@param mu: expectation value
@param sigma: standard deviation
@param a: lower boundary
@param b: upper boundary
"""
super(Normal, self).__init__()
self.__mu = float(mu)
self.__sigma = float(sigma)
self.__a, self.__b = a, b
# standard normal
self._dist = norm(loc=mu, scale=sigma)
self.__linearTrans = LinearTransformation(self._dist.cdf(self.__a),
self._dist.cdf(self.__b))
@classmethod
def by_range(cls, *args, **kws):
"""
Constructor given a interval
"""
return cls(*args, **kws)
@classmethod
def by_alpha(cls, mu, sigma, alpha):
"""
Constructor given a confidence value
@param mu: expectation value
@param sigma: standard deviation
@param alpha: confidence value
"""
U = norm(loc=mu, scale=sigma)
a = U.ppf(alpha / 2.)
b = U.ppf(1 - alpha / 2.)
return cls(mu, sigma, a, b)
def pdf(self, x):
if self.__a <= x <= self.__b:
return self._dist.pdf(x)
else:
return 0.0
def cdf(self, x):
if self.__a <= x <= self.__b:
x_unit = self._dist.cdf(x)
return self.__linearTrans.probabilisticToUnit(x_unit)
else:
raise AttributeError("normal: cdf - x out of range [%g, %g]" %
(self.__a, self.__b))
def ppf(self, x):
if 0.0 <= x <= 1.0:
x_unit = self.__linearTrans.unitToProbabilistic(x)
return self._dist.ppf(x_unit)
else:
raise AttributeError("normal: ppf - x out of range [%g, %g]" %
(self.__a, self.__b))
def mean(self):
return self.__mu
def var(self):
return self.__sigma * self.__sigma
def std(self):
return self.__sigma
def rvs(self, n=1):
samples = np.zeros(n)
i = 0
while i < n:
newSamples = self._dist.rvs(n - i)
# check range
for sample in newSamples:
if self.__a <= sample <= self.__b:
samples[i] = sample
i += 1
return samples
def getBounds(self):
return np.array([self.__a, self.__b], dtype='float')
def getDim(self):
return 1
def __str__(self):
return "N(%g, %g, %g, %g)" % (self.__mu, self.__sigma, self.__a,
self.__b)
def toJson(self):
serializationString = '"module" : "' + \
self.__module__ + '",\n'
for attrName in dir(self):
attrValue = self.__getattribute__(attrName)
serializationString += ju.parseAttribute(attrValue, attrName)
s = serializationString.rstrip(",\n")
return "{" + s + "}"
@classmethod
def fromJson(cls, jsonObject):
"""
Restores the TNormal object from the json object with its
attributes.
@param jsonObject: json object
@return: the restored TNormal object
"""
key = '_Normal__mu'
if key in jsonObject:
mu = jsonObject[key]
key = '_Normal__sigma'
if key in jsonObject:
sigma = jsonObject[key]
key = '_Normal__a'
if key in jsonObject:
a = jsonObject[key]
key = '_Normal__b'
if key in jsonObject:
b = jsonObject[key]
return Normal(mu, sigma, a, b)
def computeBF(grid, U, admissibleSet):
"""
Compute bilinear form
(A)_ij = \int phi_i phi_j dU(x)
on measure U, which is in this case supposed to be a lebesgue measure.
@param grid: Grid, sparse grid
@param U: list of distributions, Lebeasgue measure
@param admissibleSet: AdmissibleSet
@return: DataMatrix
"""
gs = grid.getStorage()
basis = getBasis(grid)
# interpolate phi_i phi_j on sparse grid with piecewise polynomial SG
# the product of two piecewise linear functions is a piecewise
# polynomial one of degree 2.
ngrid = Grid.createPolyBoundaryGrid(1, 2)
ngrid.createGridGenerator().regular(2)
ngs = ngrid.getStorage()
nodalValues = DataVector(ngs.size())
A = DataMatrix(admissibleSet.getSize(), gs.size())
b = DataVector(admissibleSet.getSize())
s = np.ndarray(gs.dim(), dtype='float')
# # pre compute basis evaluations
# basis_eval = {}
# for li in xrange(1, gs.getMaxLevel() + 1):
# for i in xrange(1, 2 ** li + 1, 2):
# # add value with it self
# x = 2 ** -li * i
# basis_eval[(li, i, li, i, x)] = basis.eval(li, i, x) * \
# basis.eval(li, i, x)
#
# # left side
# x = 2 ** -(li + 1) * (2 * i - 1)
# basis_eval[(li, i, li, i, x)] = basis.eval(li, i, x) * \
# basis.eval(li, i, x)
# # right side
# x = 2 ** -(li + 1) * (2 * i + 1)
# basis_eval[(li, i, li, i, x)] = basis.eval(li, i, x) * \
# basis.eval(li, i, x)
#
# # add values for hierarchical lower nodes
# for lj in xrange(li + 1, gs.getMaxLevel() + 1):
# a = 2 ** (lj - li)
# j = a * i - a + 1
# while j < a * i + a:
# # center
# x = 2 ** -lj * j
# basis_eval[(li, i, lj, j, x)] = basis.eval(li, i, x) * \
# basis.eval(lj, j, x)
# basis_eval[(lj, j, li, i, x)] = basis_eval[(li, i, lj, j, x)]
# # left side
# x = 2 ** -(lj + 1) * (2 * j - 1)
# basis_eval[(li, i, lj, j, x)] = basis.eval(li, i, x) * \
# basis.eval(lj, j, x)
# basis_eval[(lj, j, li, i, x)] = basis_eval[(li, i, lj, j, x)]
# # right side
# x = 2 ** -(lj + 1) * (2 * j + 1)
# basis_eval[(li, i, lj, j, x)] = basis.eval(li, i, x) * \
# basis.eval(lj, j, x)
# basis_eval[(lj, j, li, i, x)] = basis_eval[(li, i, lj, j, x)]
# j += 2
#
# print len(basis_eval)
# run over all rows
for i, gpi in enumerate(admissibleSet.values()):
# run over all columns
for j in xrange(gs.size()):
# print "%i/%i" % (i * gs.size() + j + 1, gs.size() ** 2)
gpj = gs.get(j)
for d in xrange(gs.dim()):
# get level index
lid, iid = gpi.getLevel(d), gpi.getIndex(d)
ljd, ijd = gpj.getLevel(d), gpj.getIndex(d)
# compute left and right boundary of the support of both
# basis functions
lb = max([(iid - 1) * 2 ** -lid, (ijd - 1) * 2 ** -ljd])
ub = min([(iid + 1) * 2 ** -lid, (ijd + 1) * 2 ** -ljd])
# same level, different index
if lid == ljd and iid != ijd:
s[d] = 0.
# the support does not overlap
elif lid != ljd and lb >= ub:
s[d] = 0.
else:
# ----------------------------------------------------
# do the 1d interpolation ...
# define transformation function
T = LinearTransformation(lb, ub)
for k in xrange(ngs.size()):
x = ngs.get(k).getCoord(0)
x = T.unitToProbabilistic(x)
nodalValues[k] = basis.eval(lid, iid, x) * \
basis.eval(ljd, ijd, x)
# ... by hierarchization
v = hierarchize(ngrid, nodalValues)
# discretize the following function
def f(x, y):
xp = T.unitToProbabilistic(x)
return float(y * U[d].pdf(xp))
# sparse grid quadrature
g, w, _ = discretize(ngrid, v, f, refnums=0, level=5,
useDiscreteL2Error=False)
s[d] = doQuadrature(g, w) * (ub - lb)
# fig = plt.figure()
# plotSG1d(ngrid, v)
# x = np.linspace(xlow, ub, 100)
# plt.plot(np.linspace(0, 1, 100), U[d].pdf(x))
# fig.show()
# fig = plt.figure()
# plotSG1d(g, w)
# x = np.linspace(0, 1, 100)
# plt.plot(x,
# [evalSGFunction(ngrid, v, DataVector([xi])) * U[d].pdf(T.unitToProbabilistic(xi)) for xi in x])
# fig.show()
# plt.show()
# compute the integral of it
# ----------------------------------------------------
A.set(i, j, float(np.prod(s)))
if gs.seq(gpi) == j:
b[i] = A.get(i, j)
return A, b
