def gradients_univariate_subsampled():
# Parameters!
pt = 8
x1 = Parameter(param_type="Uniform", lower=-1.0, upper=1.0, points=pt, derivative_flag=1)
parameters = [x1]
dims = len(parameters)
# Basis selection!
basis = IndexSet("Total order", orders=[pt-1])
esq = EffectiveSubsampling(parameters, basis)
A , p, w = esq.getAmatrix()
C = esq.getCmatrix()
# QR column pivotings
P = qr.mgs_pivoting(A.T)
# Now perform least squares!
basis_terms_required = basis.getCardinality()
minimum_points = np.int( (basis_terms_required + dims)/(dims + 1.) )
nodes = P[0:minimum_points]
A = getRows(A, nodes)
C = getRows(C, nodes)
#print 'Size of subsampled matrices!'
#m, n = A.shape
#print m , n
#m, n = C.shape
#print m, n
# Subselection!
w = w[nodes]
p = p[nodes,:]
W = np.mat(np.diag(np.sqrt(w)))
b = W.T * evalfunction(p, fun)
d = evalgradients(p, fungrad, 'vector')
R = np.vstack([A, C])
# Stacked least squares problem!
#x = qr.solveLSQ(np.vstack([A, C]), np.vstack([b, d]) )
#print '\n'
#print 'Final Solution!'
#print x
#print A
#print C
#print b
#print d
# Direct Elimination least squares!
x = qr.solveCLSQ(A, b, C, d)
def gradients_univariate():
# Parameters!
pt = 8
x1 = Parameter(param_type="Uniform", lower=-1.0, upper=1.0, points=pt, derivative_flag=1)
x2 = Parameter(param_type="Uniform", lower=-1.0, upper=1.0, points=pt, derivative_flag=1)
parameters = [x1, x2]
dims = len(parameters)
# Basis selection!
hyperbolic_cross = IndexSet("Total order", orders=[pt-1,pt-1])
esq = EffectiveSubsampling(parameters, hyperbolic_cross)
A , p, w = esq.getAmatrix()
C = esq.getCmatrix()
# Matrix sizes
m, n = A.shape
print m, n
print '*****************'
m, n = C.shape
print m, n
# Now perform least squares!
W = np.mat(np.diag(np.sqrt(w)))
b = W.T * evalfunction(p, fun)
d = evalgradients(p, fungrad, 'vector')
x = qr.solveLSQ(np.vstack([A, C]), np.vstack([b, d]) )
print x
def test_pseudospectral_approximation_tensor(self):
def expfun(x):
return np.exp(x[0] + x[1]) + 0.5 * np.cos(x[0] * 2 * np.pi)
# Compare actual function with polynomial approximation
s = Parameter(lower=-1, upper=1, points=6)
T = IndexSet('Tensor grid', [5, 5])
uq = Polynomial([s, s], T)
num_elements = 10
coefficients, index_set, evaled_pts = uq.getPolynomialCoefficients(
expfun)
pts, x1, x2 = meshgrid(-1.0, 1.0, num_elements, num_elements)
Approx = uq.getPolynomialApproximation(expfun, pts, coefficients)
A = np.reshape(Approx, (num_elements, num_elements))
fun = evalfunction(pts, expfun)
# Now plot this surface
fig = plt.figure()
ax = fig.gca(projection='3d')
surf = ax.plot_surface(x1,
x2,
A,
rstride=1,
cstride=1,
cmap=cm.winter,
linewidth=0,
antialiased=False,
alpha=0.5)
ax.scatter(x1, x2, fun, 'ko')
ax.set_zlim(0, 10)
ax.set_xlabel('x1')
ax.set_ylabel('x2')
ax.set_zlabel('Response')
fig.colorbar(surf, shrink=0.5, aspect=5)
def test_polynomial_and_derivative_constructions(self):
s = Parameter(lower=-1,
upper=1,
param_type='Uniform',
points=2,
derivative_flag=1)
uq_parameters = [s, s]
uq = Polynomial(uq_parameters)
num_elements = 2
pts, x1, x2 = meshgrid(-1.0, 1.0, num_elements, num_elements)
P, Q = uq.getMultivariatePolynomial(pts)
print '--------output---------'
print P
print '~'
print Q
s = Parameter(lower=-1,
upper=2,
param_type='Uniform',
points=4,
derivative_flag=0)
T = IndexSet('Tensor grid', [5])
uq = Polynomial([s])
pts = np.linspace(-1, 1, 20)
P, D = uq.getMultivariatePolynomial(pts)
print '--------output---------'
print P
print '~'
print D
def main():
# Set the parameters
x1 = Parameter(lower=38.2, upper=250.4, points=3)
x2 = Parameter(lower=0.157, upper=0.313, points=3)
parameters = [x1, x2]
# Set the polynomial basis
orders = [2, 2]
polybasis = IndexSet("Total order", orders)
print polybasis.getIndexSet()
maximum_number_of_evals = polybasis.getCardinality()
# Set up effective quadrature subsampling
esq = EffectiveSubsampling(parameters, polybasis)
Asquare = esq.getAsubsampled(maximum_number_of_evals)
print Asquare
def gradients_multivariate_subsampled():
# Parameters!
pt = 3
x1 = Parameter(param_type="Uniform", lower=-1.0, upper=1.0, points=pt, derivative_flag=1)
x2 = Parameter(param_type="Uniform", lower=-1.0, upper=1.0, points=pt, derivative_flag=1)
parameters = [x1, x2]
dims = len(parameters)
# Basis selection!
basis = IndexSet("Total order", orders=[pt-1,pt-1])
esq = EffectiveSubsampling(parameters, basis)
A , p, w = esq.getAmatrix()
C = esq.getCmatrix()
# QR column pivotings
P = qr.mgs_pivoting(A.T)
# Now perform least squares!
basis_terms_required = basis.getCardinality()
minimum_points = np.int( (basis_terms_required + dims)/(dims + 1.) ) + 5
nodes = P[0:minimum_points]
A = getRows(A, nodes)
C = getRowsC(C, nodes, dims)
m, n = A.shape
#print m , n
m, n = C.shape
#print m, n
w = w[nodes]
p = p[nodes,:]
#print p, w
W = np.mat(np.diag(np.sqrt(w)))
b = W.T * evalfunction(p, fun)
d = evalgradients(p, fungrad, 'vector')
R = np.vstack([A, C])
print np.linalg.cond(R)
print R
print np.vstack([b, d])
x = qr.solveLSQ(np.vstack([A, C]), np.vstack([b, d]) )
print '\n'
print x
"""
def test_vegetation_problem(self):
# Set the parameters
x1 = Parameter(lower=38.2, upper=250.4, points=3)
x2 = Parameter(lower=0.157, upper=0.313, points=3)
x3 = Parameter(lower=0.002, upper=0.01, points=3)
x4 = Parameter(lower=0.0002, upper=0.001, points=3)
parameters = [x1, x2, x3, x4]
# Set the polynomial basis
orders = [2, 2, 2, 2]
polybasis = IndexSet("Total order", orders)
print polybasis.getIndexSet()
maximum_number_of_evals = polybasis.getCardinality()
# Set up effective quadrature subsampling
esq = EffectiveSubsampling(parameters, polybasis)
points = esq.getEffectivelySubsampledPoints(maximum_number_of_evals)
print points
# Use the output from simulation data
#Output = [15.9881,16.5091,16.0162,15.9950,16.0310,16.4592,16.0958,15.8507,16.0757,15.9252,16.4301,16.1259,16.4682,16.0501,16.2200]
Output = [
0.0906050857157, 0.0776969827712, 0.0864368518814, 0.0932615157217,
0.0892242211848, 0.0767011023127, 0.0866207387298, 0.0977708660066,
0.0861118221655, 0.0963280722499, 0.0774124991149, 0.087565776892,
0.0768618592992, 0.0870198933408, 0.0866443598643
]
#Output = [24.8170119614, 23.7770471604, 24.6131673073, 24.9723698096, 24.6920894782, 23.7015914415, 24.6180488646, 25.2502586048, 24.5767649971, 25.1656386185, 23.7951837649, 24.5402057883, 23.7204920408, 24.5140496633, 24.4823906956]
#Output = [9.28511113565, 8.59116120376, 9.20725286751, 9.22159875619, 9.19565064461, 8.51969919061, 9.15223514391, 9.38391902559, 9.15666537065 , 9.31338865761 , 8.57543965821 , 9.0772799181, 8.53049860903, 9.17308676441, 8.98211942423]
Output = np.mat(Output)
# Solve the least squares problem
x = esq.solveLeastSquares(maximum_number_of_evals, Output.T)
print x
# Compute statistics!
vegeUQ = Statistics(x, polybasis)
mean = vegeUQ.getMean()
variance = vegeUQ.getVariance()
sobol = vegeUQ.getFirstOrderSobol()
print mean, variance
print sobol
def testoutputPDFs(self):
def expfun(x):
return np.exp(x[0] + x[1]) + 0.5 * np.cos(x[0] * 2 * np.pi)
# Compare actual function with polynomial approximation
s1 = Parameter(lower=-1,
upper=1,
points=6,
shape_parameter_A=0,
shape_parameter_B=2.5,
param_type='Gaussian')
s2 = Parameter(lower=0,
upper=5,
points=6,
shape_parameter_A=1.0,
shape_parameter_B=3.0,
param_type='Weibull')
T = IndexSet('Tensor grid', [5, 5])
uq = Polynomial([s1, s2], T)
output = uq.getPDF(expfun, graph=1)
def test_pseudospectral_coefficient_routines(self):
def expfun(x):
return np.exp(x[0] + x[1])
s = Parameter(lower=-1, upper=1, points=5)
T = IndexSet('Sparse grid', level=3, growth_rule='linear', dimension=2)
uq = Polynomial([s, s], T)
coefficients, index_set, evaled_pts = uq.getPolynomialCoefficients(
expfun)
x, y, z, max_order = twoDgrid(coefficients, index_set)
z = np.log10(np.abs(z))
# Plot of the pseudospectral coefficients
Zm = ma.masked_where(np.isnan(z), z)
plt.pcolor(y, x, Zm, cmap='jet', vmin=-14, vmax=0)
plt.title('SPAM coefficients')
plt.xlabel('i1')
plt.ylabel('i2')
plt.colorbar()
plt.xlim(0, max_order)
plt.ylim(0, max_order)
# Plot of the sparse grid points
plt.plot(evaled_pts[:, 0], evaled_pts[:, 1], 'ro')
def test_indexsets(self):
is1 = IndexSet('Tensor grid', [3, 3, 3])
print is1.getIndexSet()
print '\n'
is2 = IndexSet('Sparse grid',
level=3,
growth_rule='linear',
dimension=2)
sparse_indices, sparse_coeffs, sparse_all_elements = is2.getIndexSet()
print sparse_indices
print '\n'
is3 = IndexSet('Sparse grid',
level=2,
growth_rule='exponential',
dimension=3)
sparse_indices, sparse_coeffs, sparse_all_elements = is3.getIndexSet()
print sparse_indices
print '\n'
is4 = IndexSet('Hyperbolic basis', [5, 5], q=0.75)
print is4.getIndexSet()
print '\n'
#!/usr/bin/env python
from effective_quadratures.indexset import IndexSet
import numpy as np
import matplotlib.pyplot as plt
# Setting up the parameter
#tensor = IndexSet('Tensor grid', [3, 3])
total = IndexSet('Total order', [3, 3])
I = total.getIndexSet()
print I
# Lets plot the elements
plt.scatter(I[:,0], I[:,1], s=90, c='r', marker='o')
plt.xlabel('i1')
plt.ylabel('i2')
plt.show()