diff --git a/GPy/core/model.py b/GPy/core/model.py index 94202396..f2b188d9 100644 --- a/GPy/core/model.py +++ b/GPy/core/model.py @@ -66,7 +66,7 @@ class model(parameterised): # check constraints are okay - if isinstance(what, (priors.gamma, priors.log_Gaussian)): + if isinstance(what, (priors.gamma, priors.inverse_gamma, priors.log_Gaussian)): constrained_positive_indices = [i for i, t in zip(self.constrained_indices, self.constraints) if t.domain == 'positive'] if len(constrained_positive_indices): constrained_positive_indices = np.hstack(constrained_positive_indices) diff --git a/GPy/core/parameterised.py b/GPy/core/parameterised.py index bca242f6..7409402e 100644 --- a/GPy/core/parameterised.py +++ b/GPy/core/parameterised.py @@ -251,7 +251,18 @@ class parameterised(object): def _set_params_transformed(self, x): """ takes the vector x, which is then modified (by untying, reparameterising or inserting fixed values), and then call self._set_params""" + self._set_params(self._untransform_params(x)) + def _untransform_params(self,x): + """ + The transformation required for _set_params_transformed. + + This moves the vector x seen by the optimiser (unconstrained) to the + valid parameter vector seen by the model + + Note: + - This function is separate from _set_params_transformed for downstream flexibility + """ # work out how many places are fixed, and where they are. tricky logic! fix_places = self.fixed_indices + [t[1:] for t in self.tied_indices] if len(fix_places): @@ -272,7 +283,8 @@ class parameterised(object): [np.put(xx,i,t.f(xx[i])) for i,t in zip(self.constrained_indices, self.constraints)] if hasattr(self,'debug'): stop - self._set_params(xx) + + return xx def _get_param_names_transformed(self): """ diff --git a/GPy/core/priors.py b/GPy/core/priors.py index a5eae5b2..f9307b94 100644 --- a/GPy/core/priors.py +++ b/GPy/core/priors.py @@ -26,7 +26,6 @@ class Gaussian(prior): :param mu: mean :param sigma: standard deviation - .. Note:: Bishop 2006 notation is used throughout the code """ @@ -144,7 +143,6 @@ def gamma_from_EV(E,V): b = E/V return gamma(a,b) - class gamma(prior): """ Implementation of the Gamma probability function, coupled with random variables. @@ -155,7 +153,6 @@ class gamma(prior): .. Note:: Bishop 2006 notation is used throughout the code """ - def __init__(self,a,b): self.a = float(a) self.b = float(b) @@ -183,3 +180,30 @@ class gamma(prior): def rvs(self,n): return np.random.gamma(scale=1./self.b,shape=self.a,size=n) + +class inverse_gamma(prior): + """ + Implementation of the inverse-Gamma probability function, coupled with random variables. + + :param a: shape parameter + :param b: rate parameter (warning: it's the *inverse* of the scale) + + .. Note:: Bishop 2006 notation is used throughout the code + + """ + def __init__(self,a,b): + self.a = float(a) + self.b = float(b) + self.constant = -gammaln(self.a) + a*np.log(b) + + def __str__(self): + return "iGa("+str(np.round(self.a))+', '+str(np.round(self.b))+')' + + def lnpdf(self,x): + return self.constant - (self.a+1)*np.log(x) - self.b/x + + def lnpdf_grad(self,x): + return -(self.a+1.)/x + self.b/x**2 + + def rvs(self,n): + return 1./np.random.gamma(scale=1./self.b,shape=self.a,size=n) diff --git a/GPy/core/transformations.py b/GPy/core/transformations.py index f7e59ab6..fcbfb548 100644 --- a/GPy/core/transformations.py +++ b/GPy/core/transformations.py @@ -39,8 +39,8 @@ class logexp(transformation): return '(+ve)' class logexp_clipped(transformation): - max_bound = 1e300 - min_bound = 1e-10 + max_bound = 1e250 + min_bound = 1e-9 log_max_bound = np.log(max_bound) log_min_bound = np.log(min_bound) def __init__(self, lower=1e-6): @@ -49,11 +49,13 @@ class logexp_clipped(transformation): def f(self, x): exp = np.exp(np.clip(x, self.log_min_bound, self.log_max_bound)) f = np.log(1. + exp) + if np.isnan(f).any(): + import ipdb;ipdb.set_trace() return f def finv(self, f): return np.log(np.exp(np.clip(f, self.min_bound, self.max_bound)) - 1.) def gradfactor(self, f): - ef = np.exp(f) + ef = np.exp(f) # np.clip(f, self.min_bound, self.max_bound)) gf = (ef - 1.) / ef return np.where(f < self.lower, 0, gf) def initialize(self, f): diff --git a/GPy/examples/classification.py b/GPy/examples/classification.py index d6697d7c..9168db7c 100644 --- a/GPy/examples/classification.py +++ b/GPy/examples/classification.py @@ -9,8 +9,8 @@ import pylab as pb import numpy as np import GPy -default_seed=10000 -def crescent_data(seed=default_seed): #FIXME +default_seed = 10000 +def crescent_data(seed=default_seed): # FIXME """Run a Gaussian process classification on the crescent data. The demonstration calls the basic GP classification model and uses EP to approximate the likelihood. :param model_type: type of model to fit ['Full', 'FITC', 'DTC']. @@ -27,10 +27,10 @@ def crescent_data(seed=default_seed): #FIXME # Likelihood object distribution = GPy.likelihoods.likelihood_functions.probit() - likelihood = GPy.likelihoods.EP(data['Y'],distribution) + likelihood = GPy.likelihoods.EP(data['Y'], distribution) - m = GPy.models.GP(data['X'],likelihood,kernel) + m = GPy.models.GP(data['X'], likelihood, kernel) m.ensure_default_constraints() m.update_likelihood_approximation() @@ -54,10 +54,10 @@ def oil(): # Likelihood object distribution = GPy.likelihoods.likelihood_functions.probit() - likelihood = GPy.likelihoods.EP(data['Y'][:, 0:1],distribution) + likelihood = GPy.likelihoods.EP(data['Y'][:, 0:1], distribution) # Create GP model - m = GPy.models.GP(data['X'],likelihood=likelihood,kernel=kernel) + m = GPy.models.GP(data['X'], likelihood=likelihood, kernel=kernel) # Contrain all parameters to be positive m.constrain_positive('') @@ -85,17 +85,17 @@ def toy_linear_1d_classification(seed=default_seed): # Likelihood object distribution = GPy.likelihoods.likelihood_functions.probit() - likelihood = GPy.likelihoods.EP(Y,distribution) + likelihood = GPy.likelihoods.EP(Y, distribution) # Model definition - m = GPy.models.GP(data['X'],likelihood=likelihood,kernel=kernel) + m = GPy.models.GP(data['X'], likelihood=likelihood, kernel=kernel) m.ensure_default_constraints() # Optimize m.update_likelihood_approximation() # Parameters optimization: m.optimize() - #m.pseudo_EM() #FIXME + # m.pseudo_EM() #FIXME # Plot pb.subplot(211) @@ -121,20 +121,20 @@ def sparse_toy_linear_1d_classification(seed=default_seed): # Likelihood object distribution = GPy.likelihoods.likelihood_functions.probit() - likelihood = GPy.likelihoods.EP(Y,distribution) + likelihood = GPy.likelihoods.EP(Y, distribution) - Z = np.random.uniform(data['X'].min(),data['X'].max(),(10,1)) + Z = np.random.uniform(data['X'].min(), data['X'].max(), (10, 1)) # Model definition - m = GPy.models.sparse_GP(data['X'],likelihood=likelihood,kernel=kernel,Z=Z,normalize_X=False) - m.set('len',2.) + m = GPy.models.sparse_GP(data['X'], likelihood=likelihood, kernel=kernel, Z=Z, normalize_X=False) + m.set('len', 2.) m.ensure_default_constraints() # Optimize m.update_likelihood_approximation() # Parameters optimization: m.optimize() - #m.EPEM() #FIXME + # m.EPEM() #FIXME # Plot pb.subplot(211) @@ -162,15 +162,15 @@ def sparse_crescent_data(inducing=10, seed=default_seed): # Likelihood object distribution = GPy.likelihoods.likelihood_functions.probit() - likelihood = GPy.likelihoods.EP(data['Y'],distribution) + likelihood = GPy.likelihoods.EP(data['Y'], distribution) - sample = np.random.randint(0,data['X'].shape[0],inducing) - Z = data['X'][sample,:] + sample = np.random.randint(0, data['X'].shape[0], inducing) + Z = data['X'][sample, :] # create sparse GP EP model - m = GPy.models.sparse_GP(data['X'],likelihood=likelihood,kernel=kernel,Z=Z) + m = GPy.models.sparse_GP(data['X'], likelihood=likelihood, kernel=kernel, Z=Z) m.ensure_default_constraints() - m.set('len',10.) + m.set('len', 10.) m.update_likelihood_approximation() diff --git a/GPy/examples/dimensionality_reduction.py b/GPy/examples/dimensionality_reduction.py index ec332dfe..6230ef3a 100644 --- a/GPy/examples/dimensionality_reduction.py +++ b/GPy/examples/dimensionality_reduction.py @@ -17,11 +17,11 @@ def BGPLVM(seed=default_seed): D = 4 # generate GPLVM-like data X = np.random.rand(N, Q) - k = GPy.kern.rbf(Q) + GPy.kern.white(Q, 0.00001) + k = GPy.kern.rbf(Q) + GPy.kern.white(Q, 0.00001) K = k.K(X) Y = np.random.multivariate_normal(np.zeros(N), K, D).T - k = GPy.kern.linear(Q, ARD=True) + GPy.kern.white(Q) + k = GPy.kern.rbf(Q, ARD=True) + GPy.kern.linear(Q, ARD=True) + GPy.kern.rbf(Q, ARD=True) + GPy.kern.white(Q) # k = GPy.kern.rbf(Q) + GPy.kern.rbf(Q) + GPy.kern.white(Q) # k = GPy.kern.rbf(Q) + GPy.kern.bias(Q) + GPy.kern.white(Q, 0.00001) # k = GPy.kern.rbf(Q, ARD = False) + GPy.kern.white(Q, 0.00001) @@ -118,9 +118,9 @@ def swiss_roll(optimize=True, N=1000, M=15, Q=4, sigma=.2, plot=False): return m def BGPLVM_oil(optimize=True, N=100, Q=5, M=25, max_f_eval=4e3, plot=False, **k): + np.random.seed(0) data = GPy.util.datasets.oil() from GPy.core.transformations import logexp_clipped - np.random.seed(0) # create simple GP model kernel = GPy.kern.rbf(Q, ARD=True) + GPy.kern.bias(Q, np.exp(-2)) + GPy.kern.white(Q, np.exp(-2)) @@ -131,8 +131,7 @@ def BGPLVM_oil(optimize=True, N=100, Q=5, M=25, max_f_eval=4e3, plot=False, **k) m = GPy.models.Bayesian_GPLVM(Yn, Q, kernel=kernel, M=M, **k) m.data_labels = data['Y'][:N].argmax(axis=1) -# m.constrain('variance', logexp_clipped()) -# m.constrain('length', logexp_clipped()) + m.constrain('variance|leng', logexp_clipped()) m['lengt'] = m.X.var(0).max() / m.X.var(0) m['noise'] = Yn.var() / 100. @@ -140,10 +139,6 @@ def BGPLVM_oil(optimize=True, N=100, Q=5, M=25, max_f_eval=4e3, plot=False, **k) # optimize if optimize: -# m.unconstrain('noise'); m.constrain_fixed('noise') -# m.optimize('scg', messages=1, max_f_eval=200) -# m.unconstrain('noise') -# m.constrain('noise', logexp_clipped()) m.optimize('scg', messages=1, max_f_eval=max_f_eval) if plot: @@ -155,11 +150,6 @@ def BGPLVM_oil(optimize=True, N=100, Q=5, M=25, max_f_eval=4e3, plot=False, **k) lvm_visualizer = GPy.util.visualize.lvm_dimselect(m.X[0, :].copy(), m, data_show, latent_axes=latent_axes) # , sense_axes=sense_axes) raw_input('Press enter to finish') plt.close('all') - # # plot - # print(m) - # m.plot_latent(labels=m.data_labels) - # pb.figure() - # pb.bar(np.arange(m.kern.D), 1. / m.input_sensitivity()) return m def oil_100(): @@ -189,15 +179,6 @@ def _simulate_sincos(D1, D2, D3, N, M, Q, plot_sim=False): s3 = s3(x) sS = sS(x) -# s1 -= s1.mean() -# s2 -= s2.mean() -# s3 -= s3.mean() -# sS -= sS.mean() -# s1 /= .5 * (np.abs(s1).max() - np.abs(s1).min()) -# s2 /= .5 * (np.abs(s2).max() - np.abs(s2).min()) -# s3 /= .5 * (np.abs(s3).max() - np.abs(s3).min()) -# sS /= .5 * (np.abs(sS).max() - np.abs(sS).min()) - S1 = np.hstack([s1, sS]) S2 = np.hstack([s2, sS]) S3 = np.hstack([s3, sS]) @@ -217,16 +198,17 @@ def _simulate_sincos(D1, D2, D3, N, M, Q, plot_sim=False): Y2 /= Y2.std(0) Y3 /= Y3.std(0) - slist = [s1, s2, s3, sS] + slist = [sS, s1, s2, s3] + slist_names = ["sS", "s1", "s2", "s3"] Ylist = [Y1, Y2, Y3] if plot_sim: import pylab import itertools - fig = pylab.figure("MRD Simulation", figsize=(8, 6)) + fig = pylab.figure("MRD Simulation Data", figsize=(8, 6)) fig.clf() ax = fig.add_subplot(2, 1, 1) - labls = sorted(filter(lambda x: x.startswith("s"), locals())) + labls = slist_names for S, lab in itertools.izip(slist, labls): ax.plot(S, label=lab) ax.legend() @@ -250,7 +232,6 @@ def bgplvm_simulation_matlab_compare(): from GPy.models import mrd from GPy import kern reload(mrd); reload(kern) - # k = kern.rbf(Q, ARD=True) + kern.bias(Q, np.exp(-2)) + kern.white(Q, np.exp(-2)) k = kern.linear(Q, ARD=True) + kern.bias(Q, np.exp(-2)) + kern.white(Q, np.exp(-2)) m = Bayesian_GPLVM(Y, Q, init="PCA", M=M, kernel=k, # X=mu, @@ -260,26 +241,14 @@ def bgplvm_simulation_matlab_compare(): m.auto_scale_factor = True m['noise'] = Y.var() / 100. m['linear_variance'] = .01 - -# lscstr = 'X_variance' -# m[lscstr] = .01 -# m.unconstrain(lscstr); m.constrain_fixed(lscstr, .1) - -# cstr = 'white' -# m.unconstrain(cstr); m.constrain_bounded(cstr, .01, 1.) - -# cstr = 'noise' -# m.unconstrain(cstr); m.constrain_bounded(cstr, .01, 1.) return m -def bgplvm_simulation(burnin='scg', plot_sim=False, - max_burnin=100, true_X=False, - do_opt=True, - max_f_eval=1000): +def bgplvm_simulation(optimize='scg', + plot=True, + max_f_eval=2e4): from GPy.core.transformations import logexp_clipped - - D1, D2, D3, N, M, Q = 15, 8, 8, 350, 3, 6 - slist, Slist, Ylist = _simulate_sincos(D1, D2, D3, N, M, Q, plot_sim) + D1, D2, D3, N, M, Q = 15, 8, 8, 100, 3, 5 + slist, Slist, Ylist = _simulate_sincos(D1, D2, D3, N, M, Q, plot) from GPy.models import mrd from GPy import kern @@ -289,95 +258,23 @@ def bgplvm_simulation(burnin='scg', plot_sim=False, Y = Ylist[0] k = kern.linear(Q, ARD=True) + kern.bias(Q, np.exp(-2)) + kern.white(Q, np.exp(-2)) # + kern.bias(Q) -# k = kern.white(Q, .00001) + kern.bias(Q) m = Bayesian_GPLVM(Y, Q, init="PCA", M=M, kernel=k, _debug=True) - # m.set('noise',) - m.constrain('variance', logexp_clipped()) - - m.ensure_default_constraints() + m.constrain('variance|noise', logexp_clipped()) +# m.ensure_default_constraints() m['noise'] = Y.var() / 100. - m['linear_variance'] = .001 -# m.auto_scale_factor = True -# m.scale_factor = 1. + m['linear_variance'] = .01 - - if burnin: - print "initializing beta" - cstr = "noise" - m.unconstrain(cstr); m.constrain_fixed(cstr, Y.var() / 70.) - m.optimize(burnin, messages=1, max_f_eval=max_burnin) - - print "releasing beta" - cstr = "noise" - m.unconstrain(cstr); m.constrain_positive(cstr) - - if true_X: - true_X = np.hstack((slist[0], slist[3], 0. * np.ones((N, Q - 2)))) - m.set('X_\d', true_X) - m.constrain_fixed("X_\d") - - cstr = 'X_variance' -# m.unconstrain(cstr), m.constrain_fixed(cstr, .0001) - m.unconstrain(cstr), m.constrain_bounded(cstr, 1e-7, .1) - -# cstr = 'X_variance' -# m.unconstrain(cstr), m.constrain_bounded(cstr, 1e-3, 1.) - - # m['X_var'] = np.ones(N * Q) * .5 + np.random.randn(N * Q) * .01 - -# cstr = "iip" -# m.unconstrain(cstr); m.constrain_fixed(cstr) - -# cstr = 'variance' -# m.unconstrain(cstr), m.constrain_bounded(cstr, 1e-10, 1.) -# cstr = 'X_\d' -# m.unconstrain(cstr), m.constrain_bounded(cstr, -10., 10.) -# -# cstr = 'noise' -# m.unconstrain(cstr), m.constrain_bounded(cstr, 1e-5, 1.) -# -# cstr = 'white' -# m.unconstrain(cstr), m.constrain_bounded(cstr, 1e-6, 1.) -# -# cstr = 'linear_variance' -# m.unconstrain(cstr), m.constrain_bounded(cstr, 1e-10, 10.) - -# cstr = 'variance' -# m.unconstrain(cstr), m.constrain_bounded(cstr, 1e-10, 10.) - -# np.seterr(all='call') -# def ipdbonerr(errtype, flags): -# import ipdb; ipdb.set_trace() -# np.seterrcall(ipdbonerr) - - if do_opt and burnin: - try: - m.optimize(burnin, messages=1, max_f_eval=max_f_eval) - except: - pass - finally: - return m + if optimize: + print "Optimizing model:" + m.optimize('scg', max_iters=max_f_eval, max_f_eval=max_f_eval, messages=True) + if plot: + import pylab + m.plot_X_1d() + pylab.figure(); pylab.axis(); m.kern.plot_ARD() return m -def mrd_simulation(plot_sim=False): - # num = 2 -# ard1 = np.array([1., 1, 0, 0], dtype=float) -# ard2 = np.array([0., 1, 1, 0], dtype=float) -# ard1[ard1 == 0] = 1E-10 -# ard2[ard2 == 0] = 1E-10 - -# ard1i = 1. / ard1 -# ard2i = 1. / ard2 - -# k = GPy.kern.rbf(Q, ARD=True, lengthscale=ard1i) + GPy.kern.bias(Q, 0) + GPy.kern.white(Q, 0.0001) -# Y1 = np.random.multivariate_normal(np.zeros(N), k.K(X), D1).T -# Y1 -= Y1.mean(0) -# -# k = GPy.kern.rbf(Q, ARD=True, lengthscale=ard2i) + GPy.kern.bias(Q, 0) + GPy.kern.white(Q, 0.0001) -# Y2 = np.random.multivariate_normal(np.zeros(N), k.K(X), D2).T -# Y2 -= Y2.mean(0) -# make_params = lambda ard: np.hstack([[1], ard, [1, .3]]) - D1, D2, D3, N, M, Q = 150, 250, 300, 700, 3, 7 +def mrd_simulation(optimize=True, plot_sim=False): + D1, D2, D3, N, M, Q = 150, 250, 30, 300, 3, 7 slist, Slist, Ylist = _simulate_sincos(D1, D2, D3, N, M, Q, plot_sim) from GPy.models import mrd @@ -386,50 +283,23 @@ def mrd_simulation(plot_sim=False): reload(mrd); reload(kern) -# k = kern.rbf(2, ARD=True) + kern.bias(2) + kern.white(2) -# Y1 = np.random.multivariate_normal(np.zeros(N), k.K(S1), D1).T -# Y2 = np.random.multivariate_normal(np.zeros(N), k.K(S2), D2).T -# Y3 = np.random.multivariate_normal(np.zeros(N), k.K(S3), D3).T - -# Ylist = Ylist[0:2] - - # k = kern.rbf(Q, ARD=True) + kern.bias(Q) + kern.white(Q) - k = kern.linear(Q, [0.01] * Q, True) + kern.bias(Q, np.exp(-2)) + kern.white(Q, np.exp(-2)) - m = mrd.MRD(*Ylist, Q=Q, M=M, kernel=k, initx="concat", initz='permute', _debug=False) + m = mrd.MRD(*Ylist, Q=Q, M=M, kernel=k, initx="concat", initz='permute') for i, Y in enumerate(Ylist): m['{}_noise'.format(i + 1)] = Y.var() / 100. - m.constrain('variance', logexp_clipped()) + m.constrain('variance|noise', logexp_clipped()) m.ensure_default_constraints() -# m.auto_scale_factor = True -# cstr = 'variance' -# m.unconstrain(cstr), m.constrain_bounded(cstr, 1e-12, 1.) -# -# cstr = 'linear_variance' -# m.unconstrain(cstr), m.constrain_positive(cstr) + # DEBUG + np.seterr("raise") - print "initializing beta" - cstr = "noise" - m.unconstrain(cstr); m.constrain_fixed(cstr) - m.optimize('scg', messages=1, max_f_eval=2e3, gtol=100) + if optimize: + print "Optimizing Model:" + m.optimize('scg', messages=1, max_iters=3e3) - print "releasing beta" - cstr = "noise" - m.unconstrain(cstr); m.constrain(cstr, logexp_clipped()) - -# np.seterr(all='call') -# def ipdbonerr(errtype, flags): -# import ipdb; ipdb.set_trace() -# np.seterrcall(ipdbonerr) - - return m # , mtest - -def mrd_silhouette(): - - pass + return m def brendan_faces(): from GPy import kern diff --git a/GPy/inference/SCG.py b/GPy/inference/SCG.py index c38ef01b..83ea054f 100644 --- a/GPy/inference/SCG.py +++ b/GPy/inference/SCG.py @@ -36,8 +36,14 @@ def SCG(f, gradf, x, optargs=(), maxiters=500, max_f_eval=500, display=True, xto Returns x the optimal value for x flog : a list of all the objective values - + function_eval number of fn evaluations + status: string describing convergence status """ + + if display: + print " SCG" + print ' {0:{mi}s} {1:11s} {2:11s} {3:11s}'.format("I", "F", "Scale", "|g|", mi=len(str(maxiters))) + if xtol is None: xtol = 1e-6 if ftol is None: @@ -45,18 +51,18 @@ def SCG(f, gradf, x, optargs=(), maxiters=500, max_f_eval=500, display=True, xto if gtol is None: gtol = 1e-5 sigma0 = 1.0e-4 - fold = f(x, *optargs) # Initial function value. + fold = f(x, *optargs) # Initial function value. function_eval = 1 fnow = fold - gradnew = gradf(x, *optargs) # Initial gradient. + gradnew = gradf(x, *optargs) # Initial gradient. current_grad = np.dot(gradnew, gradnew) gradold = gradnew.copy() - d = -gradnew # Initial search direction. - success = True # Force calculation of directional derivs. - nsuccess = 0 # nsuccess counts number of successes. - beta = 1.0 # Initial scale parameter. - betamin = 1.0e-15 # Lower bound on scale. - betamax = 1.0e100 # Upper bound on scale. + d = -gradnew # Initial search direction. + success = True # Force calculation of directional derivs. + nsuccess = 0 # nsuccess counts number of successes. + beta = 1.0 # Initial scale parameter. + betamin = 1.0e-15 # Lower bound on scale. + betamax = 1.0e100 # Upper bound on scale. status = "Not converged" flog = [fold] @@ -106,12 +112,12 @@ def SCG(f, gradf, x, optargs=(), maxiters=500, max_f_eval=500, display=True, xto fnow = fold # Store relevant variables - flog.append(fnow) # Current function value + flog.append(fnow) # Current function value iteration += 1 if display: print '\r', - print 'Iter: {0:>0{mi}g} Obj:{1:> 12e} Scale:{2:> 12e} |g|:{3:> 12e}'.format(iteration, float(fnow), float(beta), float(current_grad), mi=len(str(maxiters))), + print '{0:>0{mi}g} {1:> 12e} {2:> 12e} {3:> 12e}'.format(iteration, float(fnow), float(beta), float(current_grad), mi=len(str(maxiters))), # print 'Iteration:', iteration, ' Objective:', fnow, ' Scale:', beta, '\r', sys.stdout.flush() @@ -153,5 +159,6 @@ def SCG(f, gradf, x, optargs=(), maxiters=500, max_f_eval=500, display=True, xto # iterations. status = "maxiter exceeded" - print "" + if display: + print "" return x, flog, function_eval, status diff --git a/GPy/inference/SGD.py b/GPy/inference/SGD.py index bfc6ee15..701a8c65 100644 --- a/GPy/inference/SGD.py +++ b/GPy/inference/SGD.py @@ -18,7 +18,7 @@ class opt_SGD(Optimizer): """ - def __init__(self, start, iterations = 10, learning_rate = 1e-4, momentum = 0.9, model = None, messages = False, batch_size = 1, self_paced = False, center = True, iteration_file = None, **kwargs): + def __init__(self, start, iterations = 10, learning_rate = 1e-4, momentum = 0.9, model = None, messages = False, batch_size = 1, self_paced = False, center = True, iteration_file = None, learning_rate_adaptation=None, **kwargs): self.opt_name = "Stochastic Gradient Descent" self.model = model @@ -33,6 +33,13 @@ class opt_SGD(Optimizer): self.center = center self.param_traces = [('noise',[])] self.iteration_file = iteration_file + self.learning_rate_adaptation = learning_rate_adaptation + if self.learning_rate_adaptation != None: + if self.learning_rate_adaptation == 'annealing': + self.learning_rate_0 = self.learning_rate + else: + self.learning_rate_0 = self.learning_rate.mean() + # if len([p for p in self.model.kern.parts if p.name == 'bias']) == 1: # self.param_traces.append(('bias',[])) # if len([p for p in self.model.kern.parts if p.name == 'linear']) == 1: @@ -204,6 +211,7 @@ class opt_SGD(Optimizer): ci = self.shift_constraints(j) f, fp = f_fp(self.x_opt[j]) + step[j] = self.momentum * step[j] + self.learning_rate[j] * fp self.x_opt[j] -= step[j] self.restore_constraints(ci) @@ -216,9 +224,53 @@ class opt_SGD(Optimizer): return f, step, self.model.N + def adapt_learning_rate(self, t): + if self.learning_rate_adaptation == 'adagrad': + if t > 5: + g = np.array(self.grads) + l2_g = np.sqrt(np.square(g).sum(0)) + self.learning_rate = 0.001/l2_g + else: + self.learning_rate = np.zeros_like(self.learning_rate) + elif self.learning_rate_adaptation == 'annealing': + self.learning_rate = self.learning_rate_0/(1+float(t+1)/10) + elif self.learning_rate_adaptation == 'semi_pesky': + if self.model.__class__.__name__ == 'Bayesian_GPLVM': + if t == 0: + N = self.model.N + Q = self.model.Q + M = self.model.M + + iip_pos = np.arange(2*N*Q,2*N*Q+M*Q) + mu_pos = np.arange(0,N*Q) + S_pos = np.arange(N*Q,2*N*Q) + self.vbparam_dict = {'iip': [iip_pos], + 'mu': [mu_pos], + 'S': [S_pos]} + + for k in self.vbparam_dict.keys(): + hbar_t = 0.0 + tau_t = 1000.0 + gbar_t = 0.0 + self.vbparam_dict[k].append(hbar_t) + self.vbparam_dict[k].append(tau_t) + self.vbparam_dict[k].append(gbar_t) + + g_t = self.model.grads + + for k in self.vbparam_dict.keys(): + pos, hbar_t, tau_t, gbar_t = self.vbparam_dict[k] + + gbar_t = (1-1/tau_t)*gbar_t + 1/tau_t * g_t[pos] + hbar_t = (1-1/tau_t)*hbar_t + 1/tau_t * np.dot(g_t[pos].T, g_t[pos]) + self.learning_rate[pos] = np.dot(gbar_t.T, gbar_t) / hbar_t + tau_t = tau_t*(1-self.learning_rate[pos]) + 1 + self.vbparam_dict[k] = [pos, hbar_t, tau_t, gbar_t] + + def opt(self, f_fp=None, f=None, fp=None): self.x_opt = self.model._get_params_transformed() - self.model.grads = np.zeros_like(self.x_opt) + self.grads = [] X, Y = self.model.X.copy(), self.model.likelihood.Y.copy() @@ -235,6 +287,7 @@ class opt_SGD(Optimizer): step = np.zeros_like(num_params) for it in range(self.iterations): + self.model.grads = np.zeros_like(self.x_opt) # TODO this is ugly if it == 0 or self.self_paced is False: features = np.random.permutation(Y.shape[1]) @@ -272,16 +325,17 @@ class opt_SGD(Optimizer): sys.stdout.write(status) sys.stdout.flush() self.param_traces['noise'].append(noise) - NLL.append(f) - self.fopt_trace.append(f) + NLL.append(f) + self.fopt_trace.append(NLL[-1]) # fig = plt.figure('traces') # plt.clf() # plt.plot(self.param_traces['noise']) # for k in self.param_traces.keys(): # self.param_traces[k].append(self.model.get(k)[0]) - + self.grads.append(self.model.grads.tolist()) + self.adapt_learning_rate(it) # should really be a sum(), but earlier samples in the iteration will have a very crappy ll self.f_opt = np.mean(NLL) self.model.N = N @@ -293,7 +347,7 @@ class opt_SGD(Optimizer): sigma = self.model.likelihood._variance self.model.likelihood._variance = None # invalidate cache self.model.likelihood._set_params(sigma) - + self.trace.append(self.f_opt) if self.iteration_file is not None: f = open(self.iteration_file + "iteration%d.pickle" % it, 'w') @@ -303,6 +357,6 @@ class opt_SGD(Optimizer): if self.messages != 0: sys.stdout.write('\r' + ' '*len(status)*2 + ' \r') - status = "SGD Iteration: {0: 3d}/{1: 3d} f: {2: 2.3f}\n".format(it+1, self.iterations, self.f_opt) + status = "SGD Iteration: {0: 3d}/{1: 3d} f: {2: 2.3f} max eta: {3: 1.5f}\n".format(it+1, self.iterations, self.f_opt, self.learning_rate.max()) sys.stdout.write(status) sys.stdout.flush() diff --git a/GPy/kern/bias.py b/GPy/kern/bias.py index b5883f87..09f0afa9 100644 --- a/GPy/kern/bias.py +++ b/GPy/kern/bias.py @@ -55,8 +55,9 @@ class bias(kernpart): target += self.variance def psi1(self, Z, mu, S, target): - target += self.variance - + self._psi1 = self.variance + target += self._psi1 + def psi2(self, Z, mu, S, target): target += self.variance**2 diff --git a/GPy/kern/kern.py b/GPy/kern/kern.py index c682fdcc..c9582ac8 100644 --- a/GPy/kern/kern.py +++ b/GPy/kern/kern.py @@ -315,31 +315,20 @@ class kern(parameterised): # compute the "cross" terms # TODO: input_slices needed + crossterms = 0 + for p1, p2 in itertools.combinations(self.parts, 2): - # white doesn;t combine with anything - if p1.name == 'white' or p2.name == 'white': - pass - # rbf X bias - elif p1.name == 'bias' and p2.name == 'rbf': - target += p1.variance * (p2._psi1[:, :, None] + p2._psi1[:, None, :]) - elif p2.name == 'bias' and p1.name == 'rbf': - target += p2.variance * (p1._psi1[:, :, None] + p1._psi1[:, None, :]) - # linear X bias - elif p1.name == 'bias' and p2.name == 'linear': - tmp = np.zeros((mu.shape[0], Z.shape[0])) - p2.psi1(Z, mu, S, tmp) - target += p1.variance * (tmp[:, :, None] + tmp[:, None, :]) - elif p2.name == 'bias' and p1.name == 'linear': - tmp = np.zeros((mu.shape[0], Z.shape[0])) - p1.psi1(Z, mu, S, tmp) - target += p2.variance * (tmp[:, :, None] + tmp[:, None, :]) - # rbf X linear - elif p1.name == 'linear' and p2.name == 'rbf': - raise NotImplementedError # TODO - elif p2.name == 'linear' and p1.name == 'rbf': - raise NotImplementedError # TODO - else: - raise NotImplementedError, "psi2 cannot be computed for this kernel" + + # TODO psi1 this must be faster/better/precached/more nice + tmp1 = np.zeros((mu.shape[0], Z.shape[0])) + p1.psi1(Z, mu, S, tmp1) + tmp2 = np.zeros((mu.shape[0], Z.shape[0])) + p2.psi1(Z, mu, S, tmp2) + + prod = np.multiply(tmp1, tmp2) + crossterms += prod[:,:,None] + prod[:, None, :] + + target += crossterms return target def dpsi2_dtheta(self, dL_dpsi2, Z, mu, S): @@ -348,71 +337,34 @@ class kern(parameterised): # compute the "cross" terms # TODO: better looping, input_slices - for i1, i2 in itertools.combinations(range(len(self.parts)), 2): + for i1, i2 in itertools.permutations(range(len(self.parts)), 2): p1, p2 = self.parts[i1], self.parts[i2] # ipsl1, ipsl2 = self.input_slices[i1], self.input_slices[i2] ps1, ps2 = self.param_slices[i1], self.param_slices[i2] - # white doesn;t combine with anything - if p1.name == 'white' or p2.name == 'white': - pass - # rbf X bias - elif p1.name == 'bias' and p2.name == 'rbf': - p2.dpsi1_dtheta(dL_dpsi2.sum(1) * p1.variance * 2., Z, mu, S, target[ps2]) - p1.dpsi1_dtheta(dL_dpsi2.sum(1) * p2._psi1 * 2., Z, mu, S, target[ps1]) - elif p2.name == 'bias' and p1.name == 'rbf': - p1.dpsi1_dtheta(dL_dpsi2.sum(1) * p2.variance * 2., Z, mu, S, target[ps1]) - p2.dpsi1_dtheta(dL_dpsi2.sum(1) * p1._psi1 * 2., Z, mu, S, target[ps2]) - # linear X bias - elif p1.name == 'bias' and p2.name == 'linear': - p2.dpsi1_dtheta(dL_dpsi2.sum(1) * p1.variance * 2., Z, mu, S, target[ps2]) # [ps1]) - psi1 = np.zeros((mu.shape[0], Z.shape[0])) - p2.psi1(Z, mu, S, psi1) - p1.dpsi1_dtheta(dL_dpsi2.sum(1) * psi1 * 2., Z, mu, S, target[ps1]) - elif p2.name == 'bias' and p1.name == 'linear': - p1.dpsi1_dtheta(dL_dpsi2.sum(1) * p2.variance * 2., Z, mu, S, target[ps1]) - psi1 = np.zeros((mu.shape[0], Z.shape[0])) - p1.psi1(Z, mu, S, psi1) - p2.dpsi1_dtheta(dL_dpsi2.sum(1) * psi1 * 2., Z, mu, S, target[ps2]) - # rbf X linear - elif p1.name == 'linear' and p2.name == 'rbf': - raise NotImplementedError # TODO - elif p2.name == 'linear' and p1.name == 'rbf': - raise NotImplementedError # TODO - else: - raise NotImplementedError, "psi2 cannot be computed for this kernel" + tmp = np.zeros((mu.shape[0], Z.shape[0])) + p1.psi1(Z, mu, S, tmp) + p2.dpsi1_dtheta((tmp[:,None,:]*dL_dpsi2).sum(1)*2., Z, mu, S, target[ps2]) return self._transform_gradients(target) def dpsi2_dZ(self, dL_dpsi2, Z, mu, S): target = np.zeros_like(Z) [p.dpsi2_dZ(dL_dpsi2, Z[:, i_s], mu[:, i_s], S[:, i_s], target[:, i_s]) for p, i_s in zip(self.parts, self.input_slices)] + #target *= 2 # compute the "cross" terms # TODO: we need input_slices here. - for p1, p2 in itertools.combinations(self.parts, 2): - # white doesn;t combine with anything - if p1.name == 'white' or p2.name == 'white': - pass - # rbf X bias - elif p1.name == 'bias' and p2.name == 'rbf': - p2.dpsi1_dX(dL_dpsi2.sum(1).T * p1.variance, Z, mu, S, target) - elif p2.name == 'bias' and p1.name == 'rbf': - p1.dpsi1_dZ(dL_dpsi2.sum(1).T * p2.variance, Z, mu, S, target) - # linear X bias - elif p1.name == 'bias' and p2.name == 'linear': - p2.dpsi1_dZ(dL_dpsi2.sum(1).T * p1.variance, Z, mu, S, target) - elif p2.name == 'bias' and p1.name == 'linear': - p1.dpsi1_dZ(dL_dpsi2.sum(1).T * p2.variance, Z, mu, S, target) - # rbf X linear - elif p1.name == 'linear' and p2.name == 'rbf': - raise NotImplementedError # TODO - elif p2.name == 'linear' and p1.name == 'rbf': - raise NotImplementedError # TODO - else: - raise NotImplementedError, "psi2 cannot be computed for this kernel" + for p1, p2 in itertools.permutations(self.parts, 2): + if p1.name == 'linear' and p2.name == 'linear': + raise NotImplementedError("We don't handle linear/linear cross-terms") + tmp = np.zeros((mu.shape[0], Z.shape[0])) + p1.psi1(Z, mu, S, tmp) + tmp2 = np.zeros_like(target) + p2.dpsi1_dZ((tmp[:,None,:]*dL_dpsi2).sum(1).T, Z, mu, S, tmp2) + target += tmp2 - return target * 2. + return target * 2 def dpsi2_dmuS(self, dL_dpsi2, Z, mu, S): target_mu, target_S = np.zeros((2, mu.shape[0], mu.shape[1])) @@ -420,27 +372,13 @@ class kern(parameterised): # compute the "cross" terms # TODO: we need input_slices here. - for p1, p2 in itertools.combinations(self.parts, 2): - # white doesn;t combine with anything - if p1.name == 'white' or p2.name == 'white': - pass - # rbf X bias - elif p1.name == 'bias' and p2.name == 'rbf': - p2.dpsi1_dmuS(dL_dpsi2.sum(1).T * p1.variance * 2., Z, mu, S, target_mu, target_S) - elif p2.name == 'bias' and p1.name == 'rbf': - p1.dpsi1_dmuS(dL_dpsi2.sum(1).T * p2.variance * 2., Z, mu, S, target_mu, target_S) - # linear X bias - elif p1.name == 'bias' and p2.name == 'linear': - p2.dpsi1_dmuS(dL_dpsi2.sum(1).T * p1.variance * 2., Z, mu, S, target_mu, target_S) - elif p2.name == 'bias' and p1.name == 'linear': - p1.dpsi1_dmuS(dL_dpsi2.sum(1).T * p2.variance * 2., Z, mu, S, target_mu, target_S) - # rbf X linear - elif p1.name == 'linear' and p2.name == 'rbf': - raise NotImplementedError # TODO - elif p2.name == 'linear' and p1.name == 'rbf': - raise NotImplementedError # TODO - else: - raise NotImplementedError, "psi2 cannot be computed for this kernel" + for p1, p2 in itertools.permutations(self.parts, 2): + if p1.name == 'linear' and p2.name == 'linear': + raise NotImplementedError("We don't handle linear/linear cross-terms") + + tmp = np.zeros((mu.shape[0], Z.shape[0])) + p1.psi1(Z, mu, S, tmp) + p2.dpsi1_dmuS((tmp[:,None,:]*dL_dpsi2).sum(1).T*2., Z, mu, S, target_mu, target_S) return target_mu, target_S diff --git a/GPy/kern/kernpart.py b/GPy/kern/kernpart.py index 30a1cc3d..7de150e9 100644 --- a/GPy/kern/kernpart.py +++ b/GPy/kern/kernpart.py @@ -54,5 +54,3 @@ class kernpart(object): raise NotImplementedError def dK_dX(self,X,X2,target): raise NotImplementedError - - diff --git a/GPy/kern/white.py b/GPy/kern/white.py index be6aad45..d5701cd9 100644 --- a/GPy/kern/white.py +++ b/GPy/kern/white.py @@ -18,7 +18,8 @@ class white(kernpart): self.Nparam = 1 self.name = 'white' self._set_params(np.array([variance]).flatten()) - + self._psi1 = 0 # TODO: more elegance here + def _get_params(self): return self.variance @@ -81,4 +82,3 @@ class white(kernpart): def dpsi2_dmuS(self,dL_dpsi2,Z,mu,S,target_mu,target_S): pass - diff --git a/GPy/likelihoods/Gaussian.py b/GPy/likelihoods/Gaussian.py index 71d755ed..e08fee90 100644 --- a/GPy/likelihoods/Gaussian.py +++ b/GPy/likelihoods/Gaussian.py @@ -69,6 +69,7 @@ class Gaussian(likelihood): # Note. for D>1, we need to re-normalise all the outputs independently. # This will mess up computations of diag(true_var), below. # note that the upper, lower quantiles should be the same shape as mean + # Augment the output variance with the likelihood variance and rescale. true_var = (var + np.eye(var.shape[0]) * self._variance) * self._scale ** 2 _5pc = mean - 2.*np.sqrt(np.diag(true_var)) _95pc = mean + 2.*np.sqrt(np.diag(true_var)) diff --git a/GPy/models/Bayesian_GPLVM.py b/GPy/models/Bayesian_GPLVM.py index fff96185..464d7425 100644 --- a/GPy/models/Bayesian_GPLVM.py +++ b/GPy/models/Bayesian_GPLVM.py @@ -171,9 +171,6 @@ class Bayesian_GPLVM(sparse_GP, GPLVM): self.dbound_dZtheta = sparse_GP._log_likelihood_gradients(self) return np.hstack((self.dbound_dmuS.flatten(), self.dbound_dZtheta)) - def _log_likelihood_normal_gradients(self): - Si, _, _, _ = pdinv(self.X_variance) - def plot_latent(self, which_indices=None, *args, **kwargs): if which_indices is None: @@ -208,23 +205,25 @@ class Bayesian_GPLVM(sparse_GP, GPLVM): else: colors = iter(colors) plots = [] + x = np.arange(self.X.shape[0]) for i in range(self.X.shape[1]): if axes is None: ax = fig.add_subplot(self.X.shape[1], 1, i + 1) else: ax = axes[i] ax.plot(self.X, c='k', alpha=.3) - plots.extend(ax.plot(self.X.T[i], c=colors.next(), label=r"$\mathbf{{X_{{{}}}}}$".format(i))) - ax.fill_between(np.arange(self.X.shape[0]), + plots.extend(ax.plot(x, self.X.T[i], c=colors.next(), label=r"$\mathbf{{X_{{{}}}}}$".format(i))) + ax.fill_between(x, self.X.T[i] - 2 * np.sqrt(self.X_variance.T[i]), self.X.T[i] + 2 * np.sqrt(self.X_variance.T[i]), facecolor=plots[-1].get_color(), alpha=.3) ax.legend(borderaxespad=0.) + ax.set_xlim(x.min(), x.max()) if i < self.X.shape[1] - 1: ax.set_xticklabels('') pylab.draw() - fig.tight_layout(h_pad=.01) # , rect=(0, 0, 1, .95)) + fig.tight_layout(h_pad=.01) # , rect=(0, 0, 1, .95)) return fig def _debug_filter_params(self, x): @@ -263,7 +262,7 @@ class Bayesian_GPLVM(sparse_GP, GPLVM): kllls = np.array(self._savedklll) LL, = ax1.plot(kllls[:, 0], kllls[:, 1] - kllls[:, 2], '-', label=r'$\log p(\mathbf{Y})$', mew=1.5) KL, = ax1.plot(kllls[:, 0], kllls[:, 2], '-', label=r'$\mathcal{KL}(p||q)$', mew=1.5) - L, = ax1.plot(kllls[:, 0], kllls[:, 1], '-', label=r'$L$', mew=1.5) # \mathds{E}_{q(\mathbf{X})}[p(\mathbf{Y|X})\frac{p(\mathbf{X})}{q(\mathbf{X})}] + L, = ax1.plot(kllls[:, 0], kllls[:, 1], '-', label=r'$L$', mew=1.5) # \mathds{E}_{q(\mathbf{X})}[p(\mathbf{Y|X})\frac{p(\mathbf{X})}{q(\mathbf{X})}] param_dict = dict(self._savedparams) gradient_dict = dict(self._savedgradients) @@ -411,7 +410,7 @@ class Bayesian_GPLVM(sparse_GP, GPLVM): # parameter changes # ax2 = pylab.subplot2grid((4, 1), (1, 0), 3, 1, projection='3d') - button_options = [0, 0] # [0]: clicked -- [1]: dragged + button_options = [0, 0] # [0]: clicked -- [1]: dragged def update_plots(event): if button_options[0] and not button_options[1]: @@ -483,4 +482,4 @@ class Bayesian_GPLVM(sparse_GP, GPLVM): cidp = figs[0].canvas.mpl_connect('button_press_event', onclick) cidd = figs[0].canvas.mpl_connect('motion_notify_event', motion) - return ax1, ax2, ax3, ax4, ax5 # , ax6, ax7 + return ax1, ax2, ax3, ax4, ax5 # , ax6, ax7 diff --git a/GPy/models/sparse_GP.py b/GPy/models/sparse_GP.py index 2aafab16..259db8f2 100644 --- a/GPy/models/sparse_GP.py +++ b/GPy/models/sparse_GP.py @@ -3,7 +3,7 @@ import numpy as np import pylab as pb -from ..util.linalg import mdot, jitchol, tdot, symmetrify, backsub_both_sides +from ..util.linalg import mdot, jitchol, tdot, symmetrify, backsub_both_sides,chol_inv from ..util.plot import gpplot from .. import kern from GP import GP @@ -16,9 +16,9 @@ class sparse_GP(GP): :param X: inputs :type X: np.ndarray (N x Q) :param likelihood: a likelihood instance, containing the observed data - :type likelihood: GPy.likelihood.(Gaussian | EP) - :param kernel : the kernel/covariance function. See link kernels - :type kernel: a GPy kernel + :type likelihood: GPy.likelihood.(Gaussian | EP | Laplace) + :param kernel : the kernel (covariance function). See link kernels + :type kernel: a GPy.kern.kern instance :param X_variance: The uncertainty in the measurements of X (Gaussian variance) :type X_variance: np.ndarray (N x Q) | None :param Z: inducing inputs (optional, see note) @@ -30,8 +30,6 @@ class sparse_GP(GP): """ def __init__(self, X, likelihood, kernel, Z, X_variance=None, normalize_X=False): -# self.scale_factor = 100.0 # a scaling factor to help keep the algorithm stable -# self.auto_scale_factor = False self.Z = Z self.M = Z.shape[0] self.likelihood = likelihood @@ -63,49 +61,29 @@ class sparse_GP(GP): self.psi2 = None def _computations(self): -# sf = self.scale_factor -# sf2 = sf ** 2 # factor Kmm self.Lm = jitchol(self.Kmm) # The rather complex computations of self.A - if self.likelihood.is_heteroscedastic: - assert self.likelihood.D == 1 # TODO: what if the likelihood is heterscedatic and there are multiple independent outputs? - if self.has_uncertain_inputs: -# psi2_beta_scaled = (self.psi2 * (self.likelihood.precision.flatten().reshape(self.N, 1, 1) / sf2)).sum(0) - psi2_beta_scaled = (self.psi2 * (self.likelihood.precision.flatten().reshape(self.N, 1, 1))).sum(0) - evals, evecs = linalg.eigh(psi2_beta_scaled) - clipped_evals = np.clip(evals, 0., 1e6) # TODO: make clipping configurable - if not np.allclose(evals, clipped_evals): - print "Warning: clipping posterior eigenvalues" - tmp = evecs * np.sqrt(clipped_evals) - tmp, _ = linalg.lapack.flapack.dtrtrs(self.Lm, np.asfortranarray(tmp), lower=1) - self.A = tdot(tmp) + if self.has_uncertain_inputs: + if self.likelihood.is_heteroscedastic: + psi2_beta = (self.psi2 * (self.likelihood.precision.flatten().reshape(self.N, 1, 1))).sum(0) else: -# tmp = self.psi1 * (np.sqrt(self.likelihood.precision.flatten().reshape(1, self.N)) / sf) - tmp = self.psi1 * (np.sqrt(self.likelihood.precision.flatten().reshape(1, self.N))) - tmp, _ = linalg.lapack.flapack.dtrtrs(self.Lm, np.asfortranarray(tmp), lower=1) - self.A = tdot(tmp) + psi2_beta = self.psi2.sum(0) * self.likelihood.precision + evals, evecs = linalg.eigh(psi2_beta) + clipped_evals = np.clip(evals, 0., 1e6) # TODO: make clipping configurable + tmp = evecs * np.sqrt(clipped_evals) else: - if self.has_uncertain_inputs: -# psi2_beta_scaled = (self.psi2 * (self.likelihood.precision / sf2)).sum(0) - psi2_beta_scaled = (self.psi2 * (self.likelihood.precision)).sum(0) - evals, evecs = linalg.eigh(psi2_beta_scaled) - clipped_evals = np.clip(evals, 0., 1e15) # TODO: make clipping configurable - if not np.allclose(evals, clipped_evals): - print "Warning: clipping posterior eigenvalues" - tmp = evecs * np.sqrt(clipped_evals) - tmp, _ = linalg.lapack.flapack.dtrtrs(self.Lm, np.asfortranarray(tmp), lower=1) - self.A = tdot(tmp) + if self.likelihood.is_heteroscedastic: + tmp = self.psi1 * (np.sqrt(self.likelihood.precision.flatten().reshape(1, self.N))) else: - # tmp = self.psi1 * (np.sqrt(self.likelihood.precision) / sf) tmp = self.psi1 * (np.sqrt(self.likelihood.precision)) - tmp, _ = linalg.lapack.flapack.dtrtrs(self.Lm, np.asfortranarray(tmp), lower=1) - self.A = tdot(tmp) + tmp, _ = linalg.lapack.flapack.dtrtrs(self.Lm, np.asfortranarray(tmp), lower=1) + self.A = tdot(tmp) + # factor B -# self.B = np.eye(self.M) / sf2 + self.A self.B = np.eye(self.M) + self.A self.LB = jitchol(self.B) @@ -121,8 +99,6 @@ class sparse_GP(GP): # Compute dL_dKmm tmp = tdot(self._LBi_Lmi_psi1V) self.DBi_plus_BiPBi = backsub_both_sides(self.LB, self.D * np.eye(self.M) + tmp) -# tmp = -0.5 * self.DBi_plus_BiPBi / sf2 -# tmp += -0.5 * self.B * sf2 * self.D tmp = -0.5 * self.DBi_plus_BiPBi tmp += -0.5 * self.B * self.D tmp += self.D * np.eye(self.M) @@ -132,9 +108,10 @@ class sparse_GP(GP): self.dL_dpsi0 = -0.5 * self.D * (self.likelihood.precision * np.ones([self.N, 1])).flatten() self.dL_dpsi1 = np.dot(self.Cpsi1V, self.likelihood.V.T) dL_dpsi2_beta = 0.5 * backsub_both_sides(self.Lm, self.D * np.eye(self.M) - self.DBi_plus_BiPBi) + if self.likelihood.is_heteroscedastic: if self.has_uncertain_inputs: - self.dL_dpsi2 = self.likelihood.precision[:, None, None] * dL_dpsi2_beta[None, :, :] + self.dL_dpsi2 = self.likelihood.precision.flatten()[:, None, None] * dL_dpsi2_beta[None, :, :] else: self.dL_dpsi1 += 2.*np.dot(dL_dpsi2_beta, self.psi1 * self.likelihood.precision.reshape(1, self.N)) self.dL_dpsi2 = None @@ -158,7 +135,6 @@ class sparse_GP(GP): else: # likelihood is not heterscedatic self.partial_for_likelihood = -0.5 * self.N * self.D * self.likelihood.precision + 0.5 * self.likelihood.trYYT * self.likelihood.precision ** 2 - # self.partial_for_likelihood += 0.5 * self.D * (self.psi0.sum() * self.likelihood.precision ** 2 - np.trace(self.A) * self.likelihood.precision * sf2) self.partial_for_likelihood += 0.5 * self.D * (self.psi0.sum() * self.likelihood.precision ** 2 - np.trace(self.A) * self.likelihood.precision) self.partial_for_likelihood += self.likelihood.precision * (0.5 * np.sum(self.A * self.DBi_plus_BiPBi) - np.sum(np.square(self._LBi_Lmi_psi1V))) @@ -166,16 +142,12 @@ class sparse_GP(GP): def log_likelihood(self): """ Compute the (lower bound on the) log marginal likelihood """ -# sf2 = self.scale_factor ** 2 if self.likelihood.is_heteroscedastic: A = -0.5 * self.N * self.D * np.log(2.*np.pi) + 0.5 * np.sum(np.log(self.likelihood.precision)) - 0.5 * np.sum(self.likelihood.V * self.likelihood.Y) -# B = -0.5 * self.D * (np.sum(self.likelihood.precision.flatten() * self.psi0) - np.trace(self.A) * sf2) B = -0.5 * self.D * (np.sum(self.likelihood.precision.flatten() * self.psi0) - np.trace(self.A)) else: A = -0.5 * self.N * self.D * (np.log(2.*np.pi) - np.log(self.likelihood.precision)) - 0.5 * self.likelihood.precision * self.likelihood.trYYT -# B = -0.5 * self.D * (np.sum(self.likelihood.precision * self.psi0) - np.trace(self.A) * sf2) B = -0.5 * self.D * (np.sum(self.likelihood.precision * self.psi0) - np.trace(self.A)) -# C = -self.D * (np.sum(np.log(np.diag(self.LB))) + 0.5 * self.M * np.log(sf2)) C = -self.D * (np.sum(np.log(np.diag(self.LB)))) # + 0.5 * self.M * np.log(sf2)) D = 0.5 * np.sum(np.square(self._LBi_Lmi_psi1V)) return A + B + C + D @@ -185,14 +157,6 @@ class sparse_GP(GP): self.kern._set_params(p[self.Z.size:self.Z.size + self.kern.Nparam]) self.likelihood._set_params(p[self.Z.size + self.kern.Nparam:]) self._compute_kernel_matrices() - # if self.auto_scale_factor: - # self.scale_factor = np.sqrt(self.psi2.sum(0).mean()*self.likelihood.precision) - # if self.auto_scale_factor: - # if self.likelihood.is_heteroscedastic: - # self.scale_factor = max(100,np.sqrt(self.psi2_beta_scaled.sum(0).mean())) - # else: - # self.scale_factor = np.sqrt(self.psi2.sum(0).mean()*self.likelihood.precision) -# self.scale_factor = 100. self._computations() def _get_params(self): @@ -205,11 +169,17 @@ class sparse_GP(GP): """ Approximates a non-gaussian likelihood using Expectation Propagation - For a Gaussian (or direct: TODO) likelihood, no iteration is required: + For a Gaussian likelihood, no iteration is required: this function does nothing """ if self.has_uncertain_inputs: - raise NotImplementedError, "EP approximation not implemented for uncertain inputs" + + Lmi = chol_inv(self.Lm) + Kmmi = tdot(Lmi.T) + diag_tr_psi2Kmmi = np.array([np.trace(psi2_Kmmi) for psi2_Kmmi in np.dot(self.psi2,Kmmi)]) + + self.likelihood.fit_FITC(self.Kmm,self.psi1,diag_tr_psi2Kmmi) #This uses the fit_FITC code, but does not perfomr a FITC-EP.#TODO solve potential confusion + #raise NotImplementedError, "EP approximation not implemented for uncertain inputs" else: self.likelihood.fit_DTC(self.Kmm, self.psi1) # self.likelihood.fit_FITC(self.Kmm,self.psi1,self.psi0) diff --git a/GPy/util/datasets.py b/GPy/util/datasets.py index 6bc83735..b3675a8e 100644 --- a/GPy/util/datasets.py +++ b/GPy/util/datasets.py @@ -5,6 +5,8 @@ import GPy import scipy.sparse import scipy.io import cPickle as pickle +import urllib2 as url + data_path = os.path.join(os.path.dirname(__file__), 'datasets') default_seed = 10000 @@ -15,6 +17,18 @@ def sample_class(f): c = np.where(c, 1, -1) return c +def fetch_dataset(resource, file_name, messages = True): + if messages: + print "Downloading resource: " , resource, " ... " + response = url.urlopen(resource) + # TODO: Some error checking... + html = response.read() + response.close() + with open(file_name, "w") as text_file: + text_file.write("%s"%html) + if messages: + print "Done!" + def della_gatta_TRP63_gene_expression(gene_number=None): mat_data = scipy.io.loadmat(os.path.join(data_path, 'DellaGattadata.mat')) X = np.double(mat_data['timepoints']) diff --git a/GPy/util/linalg.py b/GPy/util/linalg.py index fa7de8c1..abfb1900 100644 --- a/GPy/util/linalg.py +++ b/GPy/util/linalg.py @@ -236,7 +236,7 @@ def tdot(*args, **kwargs): else: return tdot_numpy(*args,**kwargs) -def DSYR(A,x,alpha=1.): +def DSYR_blas(A,x,alpha=1.): """ Performs a symmetric rank-1 update operation: A <- A + alpha * np.dot(x,x.T) @@ -258,6 +258,26 @@ def DSYR(A,x,alpha=1.): x_, byref(INCX), A_, byref(LDA)) symmetrify(A,upper=True) +def DSYR_numpy(A,x,alpha=1.): + """ + Performs a symmetric rank-1 update operation: + A <- A + alpha * np.dot(x,x.T) + + Arguments + --------- + :param A: Symmetric NxN np.array + :param x: Nx1 np.array + :param alpha: scalar + """ + A += alpha*np.dot(x[:,None],x[None,:]) + + +def DSYR(*args, **kwargs): + if _blas_available: + return DSYR_blas(*args,**kwargs) + else: + return DSYR_numpy(*args,**kwargs) + def symmetrify(A,upper=False): """ Take the square matrix A and make it symmetrical by copting elements from the lower half to the upper diff --git a/GPy/util/mocap_fetch.py b/GPy/util/mocap_fetch.py new file mode 100644 index 00000000..323cc5d8 --- /dev/null +++ b/GPy/util/mocap_fetch.py @@ -0,0 +1,13 @@ +import GPy +import urllib2 + +# TODO... +class mocap_fetch(base_url = 'http://mocap.cs.cmu.edu:8080/subjects/', skel_store_dir = './', motion_store_dir = './'): + def __init__(self): + self.base_url = base_url + self.store_dir = store_dir + self.motion_dict = [] + + def fetch_motions(self, motion_dict = None): + response = urllib2.urlopen(...) + html = response.read() diff --git a/GPy/util/visualize.py b/GPy/util/visualize.py index a5cf9f59..4ecf6c4f 100644 --- a/GPy/util/visualize.py +++ b/GPy/util/visualize.py @@ -44,7 +44,7 @@ class vector_show(data_show): class lvm(data_show): - def __init__(self, vals, model, data_visualize, latent_axes=None, latent_index=[0,1]): + def __init__(self, vals, model, data_visualize, latent_axes=None, sense_axes=None, latent_index=[0,1]): """Visualize a latent variable model :param model: the latent variable model to visualize. @@ -71,7 +71,7 @@ class lvm(data_show): self.data_visualize = data_visualize self.model = model self.latent_axes = latent_axes - + self.sense_axes = sense_axes self.called = False self.move_on = False self.latent_index = latent_index @@ -81,10 +81,12 @@ class lvm(data_show): self.latent_values = vals self.latent_handle = self.latent_axes.plot([0],[0],'rx',mew=2)[0] self.modify(vals) + self.show_sensitivities() def modify(self, vals): """When latent values are modified update the latent representation and ulso update the output visualization.""" y = self.model.predict(vals)[0] + print y self.data_visualize.modify(y) self.latent_handle.set_data(vals[self.latent_index[0]], vals[self.latent_index[1]]) self.axes.figure.canvas.draw() @@ -99,6 +101,7 @@ class lvm(data_show): if event.inaxes!=self.latent_axes: return self.move_on = not self.move_on self.called = True + def on_move(self, event): if event.inaxes!=self.latent_axes: return if self.called and self.move_on: @@ -107,22 +110,54 @@ class lvm(data_show): self.latent_values[self.latent_index[1]]=event.ydata self.modify(self.latent_values) + def show_sensitivities(self): + # A click in the bar chart axis for selection a dimension. + if self.sense_axes != None: + self.sense_axes.cla() + self.sense_axes.bar(np.arange(self.model.Q),1./self.model.input_sensitivity(),color='b') + + if self.latent_index[1] == self.latent_index[0]: + self.sense_axes.bar(np.array(self.latent_index[0]),1./self.model.input_sensitivity()[self.latent_index[0]],color='y') + self.sense_axes.bar(np.array(self.latent_index[1]),1./self.model.input_sensitivity()[self.latent_index[1]],color='y') + + else: + self.sense_axes.bar(np.array(self.latent_index[0]),1./self.model.input_sensitivity()[self.latent_index[0]],color='g') + self.sense_axes.bar(np.array(self.latent_index[1]),1./self.model.input_sensitivity()[self.latent_index[1]],color='r') + + self.sense_axes.figure.canvas.draw() + + class lvm_subplots(lvm): """ - latent_axes is a np array of dimension np.ceil(Q/2) + 1, - one for each pair of the axes, and the last one for the sensitiity bar chart + latent_axes is a np array of dimension np.ceil(Q/2), + one for each pair of the latent dimensions. """ - def __init__(self, vals, model, data_visualize, latent_axes=None, latent_index=[0,1]): - lvm.__init__(self, vals, model,data_visualize,latent_axes,[0,1]) + def __init__(self, vals, model, data_visualize, latent_axes=None, sense_axes=None): self.nplots = int(np.ceil(model.Q/2.))+1 - lvm.__init__(self,model,data_visualize,latent_axes,latent_index) - self.latent_values = np.zeros(2*np.ceil(self.model.Q/2.)) # possibly an extra dimension on this - assert latent_axes.size == self.nplots + assert len(latent_axes)==self.nplots + if vals==None: + vals = model.X[0, :] + self.latent_values = vals + + for i, axis in enumerate(latent_axes): + if i == self.nplots-1: + if self.nplots*2!=model.Q: + latent_index = [i*2, i*2] + lvm.__init__(self, self.latent_vals, model, data_visualize, axis, sense_axes, latent_index=latent_index) + else: + latent_index = [i*2, i*2+1] + lvm.__init__(self, self.latent_vals, model, data_visualize, axis, latent_index=latent_index) + class lvm_dimselect(lvm): """ A visualizer for latent variable models which allows selection of the latent dimensions to use by clicking on a bar chart of their length scales. + + For an example of the visualizer's use try: + + GPy.examples.dimensionality_reduction.BGPVLM_oil() + """ def __init__(self, vals, model, data_visualize, latent_axes=None, sense_axes=None, latent_index=[0, 1]): if latent_axes==None and sense_axes==None: @@ -133,24 +168,9 @@ class lvm_dimselect(lvm): else: self.sense_axes = sense_axes - lvm.__init__(self,vals,model,data_visualize,latent_axes,latent_index) - self.show_sensitivities() + lvm.__init__(self,vals,model,data_visualize,latent_axes,sense_axes,latent_index) print "use left and right mouse butons to select dimensions" - def show_sensitivities(self): - # A click in the bar chart axis for selection a dimension. - self.sense_axes.cla() - self.sense_axes.bar(np.arange(self.model.Q),1./self.model.input_sensitivity(),color='b') - - if self.latent_index[1] == self.latent_index[0]: - self.sense_axes.bar(np.array(self.latent_index[0]),1./self.model.input_sensitivity()[self.latent_index[0]],color='y') - self.sense_axes.bar(np.array(self.latent_index[1]),1./self.model.input_sensitivity()[self.latent_index[1]],color='y') - - else: - self.sense_axes.bar(np.array(self.latent_index[0]),1./self.model.input_sensitivity()[self.latent_index[0]],color='g') - self.sense_axes.bar(np.array(self.latent_index[1]),1./self.model.input_sensitivity()[self.latent_index[1]],color='r') - - self.sense_axes.figure.canvas.draw() def on_click(self, event): @@ -177,12 +197,6 @@ class lvm_dimselect(lvm): self.called = True - def on_move(self, event): - if event.inaxes!=self.latent_axes: return - if self.called and self.move_on: - self.latent_values[self.latent_index[0]]=event.xdata - self.latent_values[self.latent_index[1]]=event.ydata - self.modify(self.latent_values) def on_leave(self,event): latent_values = self.latent_values.copy() @@ -333,7 +347,7 @@ class stick_show(mocap_data_show): def process_values(self, vals): self.vals = vals.reshape((3, vals.shape[1]/3)).T.copy() - + class skeleton_show(mocap_data_show): """data_show class for visualizing motion capture data encoded as a skeleton with angles.""" def __init__(self, vals, skel, padding=0, axes=None):