def testRBFN_1D(self):
# sample from a synthetic function and see how much we improve the
# error by using the prior function
def foo(x):
return sum(sin(x * 20))
X = lhcSample([[0., 1.]], 50, seed=3)
Y = [foo(x) for x in X]
prior = RBFNMeanPrior()
prior.train(X, Y, [[0., 1.]], k=10, seed=100)
# See how well we fit the function by getting the average squared error
# over 100 samples of the function. Baseline foo(x)=0 MSE is 0.48.
# We will aim for MSE < 0.05.
S = arange(0, 1, .01)
error = mean([foo(x) - prior.mu(x) for x in S])
self.failUnless(error < 0.05)
# for debugging
if False:
figure(1)
plot(S, [foo(x) for x in S], 'b-')
plot(S, [prior.mu(x) for x in S], 'k-')
show()
def testRBFN_1D(self):
# sample from a synthetic function and see how much we improve the
# error by using the prior function
def foo(x):
return sum(sin(x*20))
X = lhcSample([[0., 1.]], 50, seed=3)
Y = [foo(x) for x in X]
prior = RBFNMeanPrior()
prior.train(X, Y, [[0., 1.]], k=10, seed=100)
# See how well we fit the function by getting the average squared error
# over 100 samples of the function. Baseline foo(x)=0 MSE is 0.48.
# We will aim for MSE < 0.05.
S = arange(0, 1, .01)
error = mean([foo(x)-prior.mu(x) for x in S])
self.failUnless(error < 0.05)
# for debugging
if False:
figure(1)
plot(S, [foo(x) for x in S], 'b-')
plot(S, [prior.mu(x) for x in S], 'k-')
show()
def testGPPrior(self):
# see how GP works with the dataprior...
def foo(x):
return sum(sin(x * 20))
bounds = [[0., 1.]]
# train prior
pX = lhcSample([[0., 1.]], 100, seed=6)
pY = [foo(x) for x in pX]
prior = RBFNMeanPrior()
prior.train(pX, pY, bounds, k=10, seed=102)
X = lhcSample([[0., 1.]], 2, seed=7)
Y = [foo(x) for x in X]
kernel = GaussianKernel_ard(array([.1]))
GP = GaussianProcess(kernel, X, Y, prior=prior)
GPnoprior = GaussianProcess(kernel, X, Y)
S = arange(0, 1, .01)
nopriorErr = mean([(foo(x) - GPnoprior.mu(x))**2 for x in S])
priorErr = mean([(foo(x) - GP.mu(x))**2 for x in S])
self.failUnless(priorErr < nopriorErr * .5)
if False:
figure(1)
clf()
plot(S, [prior.mu(x) for x in S], 'g-', alpha=0.3)
plot(S, [GPnoprior.mu(x) for x in S], 'b-', alpha=0.3)
plot(S, [GP.mu(x) for x in S], 'k-', lw=2)
plot(X, Y, 'ko')
show()
def testRNFN_10D(self):
# as above, but with a 10D test function and more data
def foo(x):
return sum(sin(x * 2))
bounds = [[0., 1.]] * 10
X = lhcSample(bounds, 100, seed=4)
Y = [foo(x) for x in X]
prior = RBFNMeanPrior()
prior.train(X, Y, bounds, k=20, seed=5)
S = lhcSample(bounds, 100, seed=6)
RBNError = mean([(foo(x) - prior.mu(x))**2 for x in S])
baselineError = mean([foo(x)**2 for x in S])
self.failUnless(RBNError < baselineError)
def testRNFN_10D(self):
# as above, but with a 10D test function and more data
def foo(x):
return sum(sin(x*2))
bounds = [[0., 1.]]*10
X = lhcSample(bounds, 100, seed=4)
Y = [foo(x) for x in X]
prior = RBFNMeanPrior()
prior.train(X, Y, bounds, k=20, seed=5)
S = lhcSample(bounds, 100, seed=6)
RBNError = mean([(foo(x)-prior.mu(x))**2 for x in S])
baselineError = mean([foo(x)**2 for x in S])
# print '\nRBN err =', RBNError
# print 'baseline =', baselineError
self.failUnless(RBNError < baselineError)
def testGPPrior(self):
# see how GP works with the dataprior...
def foo(x):
return sum(sin(x*20))
bounds = [[0., 1.]]
# train prior
pX = lhcSample([[0., 1.]], 100, seed=6)
pY = [foo(x) for x in pX]
prior = RBFNMeanPrior()
prior.train(pX, pY, bounds, k=10, seed=102)
X = lhcSample([[0., 1.]], 2, seed=7)
Y = [foo(x) for x in X]
kernel = GaussianKernel_ard(array([.1]))
GP = GaussianProcess(kernel, X, Y, prior=prior)
GPnoprior = GaussianProcess(kernel, X, Y)
S = arange(0, 1, .01)
nopriorErr = mean([(foo(x)-GPnoprior.mu(x))**2 for x in S])
priorErr = mean([(foo(x)-GP.mu(x))**2 for x in S])
# print '\nno prior Err =', nopriorErr
# print 'prior Err =', priorErr
self.failUnless(priorErr < nopriorErr*.5)
if False:
figure(1)
clf()
plot(S, [prior.mu(x) for x in S], 'g-', alpha=0.3)
plot(S, [GPnoprior.mu(x) for x in S], 'b-', alpha=0.3)
plot(S, [GP.mu(x) for x in S], 'k-', lw=2)
plot(X, Y, 'ko')
show()