diff --git a/GPy/examples/dimensionality_reduction.py b/GPy/examples/dimensionality_reduction.py index 54b36992..072ae988 100644 --- a/GPy/examples/dimensionality_reduction.py +++ b/GPy/examples/dimensionality_reduction.py @@ -3,29 +3,30 @@ import numpy as np import pylab as pb -from matplotlib import pyplot as plt +from matplotlib import pyplot as plt, pyplot import GPy +from GPy.models.mrd import MRD default_seed = np.random.seed(123344) -def BGPLVM(seed = default_seed): +def BGPLVM(seed=default_seed): N = 10 M = 3 Q = 2 D = 4 - #generate GPLVM-like data + # generate GPLVM-like data X = np.random.rand(N, Q) 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 + 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.linear(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) - m = GPy.models.Bayesian_GPLVM(Y, Q, kernel = k, M=M) + m = GPy.models.Bayesian_GPLVM(Y, Q, kernel=k, M=M) m.constrain_positive('(rbf|bias|noise|white|S)') # m.constrain_fixed('S', 1) @@ -38,44 +39,53 @@ def BGPLVM(seed = default_seed): # pb.title('After optimisation') m.ensure_default_constraints() m.randomize() - m.checkgrad(verbose = 1) + m.checkgrad(verbose=1) return m +<<<<<<< HEAD def GPLVM_oil_100(optimize=True): data = GPy.util.datasets.oil_100() # create simple GP model kernel = GPy.kern.rbf(6, ARD = True) + GPy.kern.bias(6) m = GPy.models.GPLVM(data['X'], 6, kernel=kernel) +======= +def GPLVM_oil_100(optimize=True, M=15): + data = GPy.util.datasets.oil_100() + + # create simple GP model + kernel = GPy.kern.rbf(6, ARD=True) + GPy.kern.bias(6) + m = GPy.models.GPLVM(data['X'], 6, kernel=kernel, M=M) +>>>>>>> f6b98160a7c0ace6ca5f795aeb878d30b8aaf6a4 m.data_labels = data['Y'].argmax(axis=1) # optimize m.ensure_default_constraints() if optimize: - m.optimize('scg',messages=1) + m.optimize('scg', messages=1) # plot print(m) m.plot_latent(labels=m.data_labels) return m -def BGPLVM_oil(optimize=True,N=100,Q=10,M=15,max_f_eval=300): +def BGPLVM_oil(optimize=True, N=100, Q=10, M=15, max_f_eval=300): data = GPy.util.datasets.oil() # create simple GP model - kernel = GPy.kern.rbf(Q, ARD = True) + GPy.kern.bias(Q) + GPy.kern.white(Q,0.001) - m = GPy.models.Bayesian_GPLVM(data['X'][:N], Q, kernel = kernel,M=M) + kernel = GPy.kern.rbf(Q, ARD=True) + GPy.kern.bias(Q) + GPy.kern.white(Q, 0.001) + m = GPy.models.Bayesian_GPLVM(data['X'][:N], Q, kernel=kernel, M=M) m.data_labels = data['Y'][:N].argmax(axis=1) # optimize if optimize: - m.constrain_fixed('noise',0.05) + m.constrain_fixed('noise', 0.05) m.ensure_default_constraints() - m.optimize('scg',messages=1,max_f_eval=max(80,max_f_eval)) + m.optimize('scg', messages=1, max_f_eval=max(80, max_f_eval)) m.unconstrain('noise') m.constrain_positive('noise') - m.optimize('scg',messages=1,max_f_eval=max(0,max_f_eval-80)) + m.optimize('scg', messages=1, max_f_eval=max(0, max_f_eval - 80)) else: m.ensure_default_constraints() @@ -83,7 +93,7 @@ def BGPLVM_oil(optimize=True,N=100,Q=10,M=15,max_f_eval=300): print(m) m.plot_latent(labels=m.data_labels) pb.figure() - pb.bar(np.arange(m.kern.D),1./m.input_sensitivity()) + pb.bar(np.arange(m.kern.D), 1. / m.input_sensitivity()) return m def oil_100(): @@ -96,7 +106,52 @@ def oil_100(): # plot print(m) - #m.plot_latent(labels=data['Y'].argmax(axis=1)) + # m.plot_latent(labels=data['Y'].argmax(axis=1)) + return m + +def mrd_simulation(): + # 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, N, M, Q = 50, 100, 150, 15, 4 + x = np.linspace(0, 2 * np.pi, N)[:, None] + + s1 = np.vectorize(lambda x: np.sin(x)) + s2 = np.vectorize(lambda x: np.cos(x)) + sS = np.vectorize(lambda x: np.sin(2 * x)) + + S1 = np.hstack([s1(x), sS(x)]) + S2 = np.hstack([s2(x), sS(x)]) + + Y1 = S1.dot(np.random.randn(S1.shape[1], D1)) + Y2 = S2.dot(np.random.randn(S2.shape[1], D2)) + + k = GPy.kern.rbf(Q, ARD=True) + GPy.kern.bias(Q) + GPy.kern.white(Q) + + m = MRD(Y1, Y2, Q=Q, M=M, kernel=k, init="PCA", _debug=False) + m.ensure_default_constraints() + +# fig = pyplot.figure("expected", figsize=(8, 3)) +# ax = fig.add_subplot(121) +# ax.bar(np.arange(ard1.size) + .1, ard1) +# ax = fig.add_subplot(122) +# ax.bar(np.arange(ard2.size) + .1, ard2) + return m def brendan_faces(): @@ -109,7 +164,7 @@ def brendan_faces(): m.optimize(messages=1, max_f_eval=10000) ax = m.plot_latent() - y = m.likelihood.Y[0,:] + y = m.likelihood.Y[0, :] data_show = GPy.util.visualize.image_show(y[None, :], dimensions=(20, 28), transpose=True, invert=False, scale=False) lvm_visualizer = GPy.util.visualize.lvm(m, data_show, ax) raw_input('Press enter to finish') @@ -126,10 +181,39 @@ def stick(): m.optimize(messages=1, max_f_eval=10000) ax = m.plot_latent() - y = m.likelihood.Y[0,:] + y = m.likelihood.Y[0, :] data_show = GPy.util.visualize.stick_show(y[None, :], connect=data['connect']) lvm_visualizer = GPy.util.visualize.lvm(m, data_show, ax) raw_input('Press enter to finish') plt.close('all') return m + +# def BGPLVM_oil(): +# data = GPy.util.datasets.oil() +# Y, X = data['Y'], data['X'] +# X -= X.mean(axis=0) +# X /= X.std(axis=0) +# +# Q = 10 +# M = 30 +# +# kernel = GPy.kern.rbf(Q, ARD=True) + GPy.kern.bias(Q) + GPy.kern.white(Q) +# m = GPy.models.Bayesian_GPLVM(X, Q, kernel=kernel, M=M) +# # m.scale_factor = 100.0 +# m.constrain_positive('(white|noise|bias|X_variance|rbf_variance|rbf_length)') +# from sklearn import cluster +# km = cluster.KMeans(M, verbose=10) +# Z = km.fit(m.X).cluster_centers_ +# # Z = GPy.util.misc.kmm_init(m.X, M) +# m.set('iip', Z) +# m.set('bias', 1e-4) +# # optimize +# # m.ensure_default_constraints() +# +# import pdb; pdb.set_trace() +# m.optimize('tnc', messages=1) +# print m +# m.plot_latent(labels=data['Y'].argmax(axis=1)) +# return m + diff --git a/GPy/inference/SCG.py b/GPy/inference/SCG.py index 0e85f243..912641f6 100644 --- a/GPy/inference/SCG.py +++ b/GPy/inference/SCG.py @@ -104,7 +104,8 @@ def SCG(f, gradf, x, optargs=(), maxiters=500, max_f_eval=500, display=True, xto iteration += 1 if display: - print 'Iteration:', iteration, ' Objective:', fnow, ' Scale:', beta, '\r', + print 'Iteration: {0:<5g} Objective:{1:< 12g} Scale:{2:< 12g}\r'.format(iteration, fnow, beta), + # print 'Iteration:', iteration, ' Objective:', fnow, ' Scale:', beta, '\r', sys.stdout.flush() if success: diff --git a/GPy/inference/SGD.py b/GPy/inference/SGD.py index 13a325b0..5d1b673d 100644 --- a/GPy/inference/SGD.py +++ b/GPy/inference/SGD.py @@ -75,7 +75,10 @@ class opt_SGD(Optimizer): return (np.isnan(data).sum(axis=1) == 0) def check_for_missing(self, data): - return np.isnan(data).sum() > 0 + if sp.sparse.issparse(self.model.likelihood.Y): + return True + else: + return np.isnan(data).sum() > 0 def subset_parameter_vector(self, x, samples, param_shapes): subset = np.array([], dtype = int) @@ -149,10 +152,10 @@ class opt_SGD(Optimizer): else: raise NotImplementedError - def step_with_missing_data(self, f_fp, X, step, shapes, sparse_matrix): + def step_with_missing_data(self, f_fp, X, step, shapes): N, Q = X.shape - if not sparse_matrix: + if not sp.sparse.issparse(self.model.likelihood.Y): Y = self.model.likelihood.Y samples = self.non_null_samples(self.model.likelihood.Y) self.model.N = samples.sum() @@ -165,7 +168,6 @@ class opt_SGD(Optimizer): if self.model.N == 0 or Y.std() == 0.0: return 0, step, self.model.N - # FIXME: get rid of self.center, everything should be centered by default self.model.likelihood._mean = Y.mean() self.model.likelihood._std = Y.std() self.model.likelihood.set_data(Y) @@ -173,10 +175,6 @@ class opt_SGD(Optimizer): j = self.subset_parameter_vector(self.x_opt, samples, shapes) self.model.X = X[samples] - # if self.center: - # self.model.likelihood.Y -= self.model.likelihood.Y.mean() - # self.model.likelihood.Y /= self.model.likelihood.Y.std() - model_name = self.model.__class__.__name__ if model_name == 'Bayesian_GPLVM': @@ -185,33 +183,31 @@ class opt_SGD(Optimizer): b, p = self.shift_constraints(j) f, fp = f_fp(self.x_opt[j]) - # momentum_term = self.momentum * step[j] - # step[j] = self.learning_rate[j] * fp - # self.x_opt[j] -= step[j] + momentum_term - step[j] = self.momentum * step[j] + self.learning_rate[j] * fp self.x_opt[j] -= step[j] self.restore_constraints(b, p) + # restore likelihood _mean and _std, otherwise when we call set_data(y) on + # the next feature, it will get normalized with the mean and std of this one. + self.model.likelihood._mean = 0 + self.model.likelihood._std = 1 return f, step, self.model.N def opt(self, f_fp=None, f=None, fp=None): self.x_opt = self.model._get_params_transformed() X, Y = self.model.X.copy(), self.model.likelihood.Y.copy() - N, Q = self.model.X.shape - D = self.model.likelihood.Y.shape[1] - self.trace = [] - sparse_matrix = sp.sparse.issparse(self.model.likelihood.Y) - missing_data = True - if not sparse_matrix: - missing_data = self.check_for_missing(self.model.likelihood.Y) self.model.likelihood.YYT = None self.model.likelihood.trYYT = None self.model.likelihood._mean = 0.0 self.model.likelihood._std = 1.0 + + N, Q = self.model.X.shape + D = self.model.likelihood.Y.shape[1] num_params = self.model._get_params() + self.trace = [] + missing_data = self.check_for_missing(self.model.likelihood.Y) step = np.zeros_like(num_params) for it in range(self.iterations): @@ -224,34 +220,26 @@ class opt_SGD(Optimizer): b = len(features)/self.batch_size features = [features[i::b] for i in range(b)] NLL = [] - count = 0 - last_printed_count = -1 - for j in features: - count += 1 + for count, j in enumerate(features): self.model.D = len(j) self.model.likelihood.D = len(j) self.model.likelihood.set_data(Y[:, j]) - if missing_data or sparse_matrix: + if missing_data: shapes = self.get_param_shapes(N, Q) - f, step, Nj = self.step_with_missing_data(f_fp, X, step, shapes, sparse_matrix) + f, step, Nj = self.step_with_missing_data(f_fp, X, step, shapes) else: Nj = N f, fp = f_fp(self.x_opt) - # momentum_term = self.momentum * step # compute momentum using update(t-1) - # step = self.learning_rate * fp # compute update(t) - # self.x_opt -= step + momentum_term step = self.momentum * step + self.learning_rate * fp self.x_opt -= step - if self.messages == 2: noise = self.model.likelihood._variance status = "evaluating {feature: 5d}/{tot: 5d} \t f: {f: 2.3f} \t non-missing: {nm: 4d}\t noise: {noise: 2.4f}\r".format(feature = count, tot = len(features), f = f, nm = Nj, noise = noise) sys.stdout.write(status) sys.stdout.flush() - last_printed_count = count self.param_traces['noise'].append(noise) NLL.append(f) @@ -269,7 +257,6 @@ class opt_SGD(Optimizer): self.model.likelihood.D = D self.model.likelihood.Y = Y - # self.model.Youter = np.dot(Y, Y.T) self.trace.append(self.f_opt) if self.iteration_file is not None: f = open(self.iteration_file + "iteration%d.pickle" % it, 'w') @@ -282,7 +269,3 @@ class opt_SGD(Optimizer): status = "SGD Iteration: {0: 3d}/{1: 3d} f: {2: 2.3f}\n".format(it+1, self.iterations, self.f_opt) sys.stdout.write(status) sys.stdout.flush() - - - - diff --git a/GPy/kern/kern.py b/GPy/kern/kern.py index 7d3b1737..447819c1 100644 --- a/GPy/kern/kern.py +++ b/GPy/kern/kern.py @@ -52,7 +52,7 @@ class kern(parameterised): parameterised.__init__(self) - def plot_ARD(self): + def plot_ARD(self, ax=pb.gca()): """ If an ARD kernel is present, it bar-plots the ARD parameters @@ -60,17 +60,17 @@ class kern(parameterised): """ for p in self.parts: if hasattr(p, 'ARD') and p.ARD: - pb.figure() - pb.title('ARD parameters, %s kernel' % p.name) + ax.set_title('ARD parameters, %s kernel' % p.name) if p.name == 'linear': ard_params = p.variances else: ard_params = 1./p.lengthscale - pb.bar(np.arange(len(ard_params))-0.4, ard_params) - - + ax.bar(np.arange(len(ard_params)) - 0.4, ard_params) + ax.set_xticks(np.arange(len(ard_params)), + ["${}$".format(i + 1) for i in range(len(ard_params))]) + return ax def _transform_gradients(self,g): x = self._get_params() diff --git a/GPy/kern/rbf.py b/GPy/kern/rbf.py index 4069f07d..a654cd0f 100644 --- a/GPy/kern/rbf.py +++ b/GPy/kern/rbf.py @@ -227,9 +227,8 @@ class rbf(kernpart): def weave_psi2(self,mu,Zhat): weave_options = {'headers' : [''], - 'extra_compile_args': ['-fopenmp -march=native'], - 'extra_link_args' : ['-lgomp'], - 'compiler' : 'gcc'} + 'extra_compile_args': ['-fopenmp -O3'], #-march=native'], + 'extra_link_args' : ['-lgomp']} N,Q = mu.shape M = Zhat.shape[0] diff --git a/GPy/models/Bayesian_GPLVM.py b/GPy/models/Bayesian_GPLVM.py index ee485e76..dd55b38f 100644 --- a/GPy/models/Bayesian_GPLVM.py +++ b/GPy/models/Bayesian_GPLVM.py @@ -22,7 +22,7 @@ class Bayesian_GPLVM(sparse_GP, GPLVM): :type init: 'PCA'|'random' """ - def __init__(self, Y, Q, X = None, X_variance = None, init='PCA', M=10, Z=None, kernel=None, **kwargs): + def __init__(self, Y, Q, X=None, X_variance=None, init='PCA', M=10, Z=None, kernel=None, **kwargs): if X == None: X = self.initialise_latent(init, Q, Y) @@ -31,7 +31,7 @@ class Bayesian_GPLVM(sparse_GP, GPLVM): if Z is None: Z = np.random.permutation(X.copy())[:M] - assert Z.shape[1]==X.shape[1] + assert Z.shape[1] == X.shape[1] if kernel is None: kernel = kern.rbf(Q) + kern.white(Q) @@ -40,8 +40,8 @@ class Bayesian_GPLVM(sparse_GP, GPLVM): sparse_GP.__init__(self, X, Gaussian(Y), kernel, Z=Z, X_variance=X_variance, **kwargs) def _get_param_names(self): - X_names = sum([['X_%i_%i'%(n,q) for q in range(self.Q)] for n in range(self.N)],[]) - S_names = sum([['X_variance_%i_%i'%(n,q) for q in range(self.Q)] for n in range(self.N)],[]) + X_names = sum([['X_%i_%i' % (n, q) for q in range(self.Q)] for n in range(self.N)], []) + S_names = sum([['X_variance_%i_%i' % (n, q) for q in range(self.Q)] for n in range(self.N)], []) return (X_names + S_names + sparse_GP._get_param_names(self)) def _get_params(self): @@ -56,35 +56,43 @@ class Bayesian_GPLVM(sparse_GP, GPLVM): """ return np.hstack((self.X.flatten(), self.X_variance.flatten(), sparse_GP._get_params(self))) - def _set_params(self,x): + def _set_params(self, x): N, Q = self.N, self.Q - self.X = x[:self.X.size].reshape(N,Q).copy() - self.X_variance = x[(N*Q):(2*N*Q)].reshape(N,Q).copy() - sparse_GP._set_params(self, x[(2*N*Q):]) + self.X = x[:self.X.size].reshape(N, Q).copy() + self.X_variance = x[(N * Q):(2 * N * Q)].reshape(N, Q).copy() + sparse_GP._set_params(self, x[(2 * N * Q):]) + + + def dKL_dmuS(self): + dKL_dS = (1. - (1. / self.X_variance)) * 0.5 + dKL_dmu = self.X + return dKL_dmu, dKL_dS def dL_dmuS(self): - dL_dmu_psi0, dL_dS_psi0 = self.kern.dpsi1_dmuS(self.dL_dpsi1,self.Z,self.X,self.X_variance) - dL_dmu_psi1, dL_dS_psi1 = self.kern.dpsi0_dmuS(self.dL_dpsi0,self.Z,self.X,self.X_variance) - dL_dmu_psi2, dL_dS_psi2 = self.kern.dpsi2_dmuS(self.dL_dpsi2,self.Z,self.X,self.X_variance) + dL_dmu_psi0, dL_dS_psi0 = self.kern.dpsi1_dmuS(self.dL_dpsi1, self.Z, self.X, self.X_variance) + dL_dmu_psi1, dL_dS_psi1 = self.kern.dpsi0_dmuS(self.dL_dpsi0, self.Z, self.X, self.X_variance) + dL_dmu_psi2, dL_dS_psi2 = self.kern.dpsi2_dmuS(self.dL_dpsi2, self.Z, self.X, self.X_variance) dL_dmu = dL_dmu_psi0 + dL_dmu_psi1 + dL_dmu_psi2 dL_dS = dL_dS_psi0 + dL_dS_psi1 + dL_dS_psi2 - dKL_dS = (1. - (1./self.X_variance))*0.5 - dKL_dmu = self.X - return np.hstack(((dL_dmu - dKL_dmu).flatten(), (dL_dS - dKL_dS).flatten())) + return dL_dmu, dL_dS def KL_divergence(self): var_mean = np.square(self.X).sum() var_S = np.sum(self.X_variance - np.log(self.X_variance)) - return 0.5*(var_mean + var_S) - 0.5*self.Q*self.N + return 0.5 * (var_mean + var_S) - 0.5 * self.Q * self.N def log_likelihood(self): return sparse_GP.log_likelihood(self) - self.KL_divergence() def _log_likelihood_gradients(self): - return np.hstack((self.dL_dmuS().flatten(), sparse_GP._log_likelihood_gradients(self))) + dKL_dmu, dKL_dS = self.dKL_dmuS() + dL_dmu, dL_dS = self.dL_dmuS() + # TODO: find way to make faster + dbound_dmuS = np.hstack(((dL_dmu - dKL_dmu).flatten(), (dL_dS - dKL_dS).flatten())) + return np.hstack((dbound_dmuS.flatten(), sparse_GP._log_likelihood_gradients(self))) - def plot_latent(self, which_indices=None,*args, **kwargs): + def plot_latent(self, which_indices=None, *args, **kwargs): if which_indices is None: try: @@ -93,6 +101,6 @@ class Bayesian_GPLVM(sparse_GP, GPLVM): raise ValueError, "cannot Atomatically determine which dimensions to plot, please pass 'which_indices'" else: input_1, input_2 = which_indices - ax = GPLVM.plot_latent(self, which_indices=[input_1, input_2],*args, **kwargs) + ax = GPLVM.plot_latent(self, which_indices=[input_1, input_2], *args, **kwargs) ax.plot(self.Z[:, input_1], self.Z[:, input_2], '^w') return ax diff --git a/GPy/models/GPLVM.py b/GPy/models/GPLVM.py index 33c59748..d0491de0 100644 --- a/GPy/models/GPLVM.py +++ b/GPy/models/GPLVM.py @@ -60,7 +60,7 @@ class GPLVM(GP): mu, var, upper, lower = self.predict(Xnew) pb.plot(mu[:,0], mu[:,1],'k',linewidth=1.5) - def plot_latent(self,labels=None, which_indices=None, resolution=50,ax=pb.gca()): + def plot_latent(self, labels=None, which_indices=None, resolution=50, ax=pb.gca()): """ :param labels: a np.array of size self.N containing labels for the points (can be number, strings, etc) :param resolution: the resolution of the grid on which to evaluate the predictive variance @@ -90,7 +90,7 @@ class GPLVM(GP): Xtest_full[:, :2] = Xtest mu, var, low, up = self.predict(Xtest_full) var = var[:, :1] - ax.imshow(var.reshape(resolution,resolution).T[::-1,:], + ax.imshow(var.reshape(resolution, resolution).T[::-1, :], extent=[xmin[0], xmax[0], xmin[1], xmax[1]], cmap=pb.cm.binary,interpolation='bilinear') for i,ul in enumerate(np.unique(labels)): diff --git a/GPy/models/__init__.py b/GPy/models/__init__.py index f442dc67..91cc60e3 100644 --- a/GPy/models/__init__.py +++ b/GPy/models/__init__.py @@ -11,4 +11,7 @@ from warped_GP import warpedGP from sparse_GPLVM import sparse_GPLVM from uncollapsed_sparse_GP import uncollapsed_sparse_GP from Bayesian_GPLVM import Bayesian_GPLVM +import mrd +MRD = mrd.MRD +del mrd from generalized_FITC import generalized_FITC diff --git a/GPy/models/mrd.py b/GPy/models/mrd.py new file mode 100644 index 00000000..bd1c3528 --- /dev/null +++ b/GPy/models/mrd.py @@ -0,0 +1,180 @@ +''' +Created on 10 Apr 2013 + +@author: Max Zwiessele +''' +from GPy.core import model +from GPy.models.Bayesian_GPLVM import Bayesian_GPLVM +import numpy +from GPy.models.sparse_GP import sparse_GP +import itertools +from matplotlib import pyplot +import pylab + + +class MRD(model): + """ + Do MRD on given Datasets in Ylist. + All Ys in Ylist are in [N x Dn], where Dn can be different per Yn, + N must be shared across datasets though. + + :param Ylist...: observed datasets + :type Ylist: [np.ndarray] + :param names: names for different gplvm models + :type names: [str] + :param Q: latent dimensionality + :type Q: int + :param init: initialisation method for the latent space + :type init: 'PCA'|'random' + :param X: + Initial latent space + :param X_variance: + Initial latent space variance + :param init: [PCA|random] + initialization method to use + :param M: + number of inducing inputs to use + :param Z: + initial inducing inputs + :param kernel: + kernel to use + """ + def __init__(self, *Ylist, **kwargs): + self._debug = False + if kwargs.has_key("_debug"): + self._debug = kwargs['_debug'] + del kwargs['_debug'] + if kwargs.has_key("names"): + self.names = kwargs['names'] + del kwargs['names'] + else: + self.names = ["{}".format(i + 1) for i in range(len(Ylist))] + if kwargs.has_key('kernel'): + kernel = kwargs['kernel'] + k = lambda: kernel.copy() + del kwargs['kernel'] + else: + k = lambda: None + self.bgplvms = [Bayesian_GPLVM(Y, kernel=k(), **kwargs) for Y in Ylist] + self.gref = self.bgplvms[0] + nparams = numpy.array([0] + [sparse_GP._get_params(g).size - g.Z.size for g in self.bgplvms]) + self.nparams = nparams.cumsum() + self.Q = self.gref.Q + self.N = self.gref.N + self.NQ = self.N * self.Q + self.M = self.gref.M + self.MQ = self.M * self.Q + + model.__init__(self) # @UndefinedVariable + + def _get_param_names(self): + # X_names = sum([['X_%i_%i' % (n, q) for q in range(self.Q)] for n in range(self.N)], []) + # S_names = sum([['X_variance_%i_%i' % (n, q) for q in range(self.Q)] for n in range(self.N)], []) + n1 = self.gref._get_param_names() + n1var = n1[:self.NQ * 2 + self.MQ] + map_names = lambda ns, name: map(lambda x: "{1}_{0}".format(*x), + itertools.izip(ns, + itertools.repeat(name))) + return list(itertools.chain(n1var, *(map_names(\ + sparse_GP._get_param_names(g)[self.MQ:], n) \ + for g, n in zip(self.bgplvms, self.names)))) + + def _get_params(self): + """ + return parameter list containing private and shared parameters as follows: + + ================================================================= + | mu | S | Z || theta1 | theta2 | .. | thetaN | + ================================================================= + """ + X = self.gref.X.flatten() + X_var = self.gref.X_variance.flatten() + Z = self.gref.Z.flatten() + thetas = [sparse_GP._get_params(g)[g.Z.size:] for g in self.bgplvms] + params = numpy.hstack([X, X_var, Z, numpy.hstack(thetas)]) + return params + + def _set_var_params(self, g, X, X_var, Z): + g.X = X + g.X_variance = X_var + g.Z = Z + + def _set_kern_params(self, g, p): + g.kern._set_params(p[:g.kern.Nparam]) + g.likelihood._set_params(p[g.kern.Nparam:]) + + def _set_params(self, x): + start = 0; end = self.NQ + X = x[start:end].reshape(self.N, self.Q).copy() + start = end; end += start + X_var = x[start:end].reshape(self.N, self.Q).copy() + start = end; end += self.MQ + Z = x[start:end].reshape(self.M, self.Q).copy() + thetas = x[end:] + + # set params for all others: + for g, s, e in itertools.izip(self.bgplvms, self.nparams, self.nparams[1:]): + self._set_var_params(g, X, X_var, Z) + self._set_kern_params(g, thetas[s:e].copy()) + g._compute_kernel_matrices() + g._computations() + + + def log_likelihood(self): + ll = +self.gref.KL_divergence() + for g in self.bgplvms: + ll -= sparse_GP.log_likelihood(g) + return -ll + + def _log_likelihood_gradients(self): + dLdmu, dLdS = reduce(lambda a, b: [a[0] + b[0], a[1] + b[1]], (g.dL_dmuS() for g in self.bgplvms)) + dKLmu, dKLdS = self.gref.dKL_dmuS() + dLdmu -= dKLmu + dLdS -= dKLdS + dLdmuS = numpy.hstack((dLdmu.flatten(), dLdS.flatten())).flatten() + dldzt1 = reduce(lambda a, b: a + b, (sparse_GP._log_likelihood_gradients(g)[:self.MQ] for g in self.bgplvms)) + + return numpy.hstack((dLdmuS, + dldzt1, + numpy.hstack([numpy.hstack([g.dL_dtheta(), + g.likelihood._gradients(\ + partial=g.partial_for_likelihood)]) \ + for g in self.bgplvms]))) + + def plot_X(self): + fig = pylab.figure("MRD X", figsize=(4 * len(self.bgplvms), 3)) + fig.clf() + for i, g in enumerate(self.bgplvms): + ax = fig.add_subplot(1, len(self.bgplvms), i + 1) + ax.imshow(g.X) + pylab.draw() + fig.tight_layout() + return fig + + def plot_predict(self): + fig = pylab.figure("MRD Predictions", figsize=(4 * len(self.bgplvms), 3)) + fig.clf() + for i, g in enumerate(self.bgplvms): + ax = fig.add_subplot(1, len(self.bgplvms), i + 1) + ax.imshow(g.predict(g.X)[0]) + pylab.draw() + fig.tight_layout() + return fig + + def plot_scales(self, *args, **kwargs): + fig = pylab.figure("MRD Scales", figsize=(4 * len(self.bgplvms), 3)) + for i, g in enumerate(self.bgplvms): + ax = fig.add_subplot(1, len(self.bgplvms), i + 1) + g.kern.plot_ARD(ax=ax, *args, **kwargs) + pylab.draw() + fig.tight_layout() + return fig + + def plot_latent(self, *args, **kwargs): + fig = pylab.figure("MRD Latent Spaces", figsize=(4 * len(self.bgplvms), 3)) + for i, g in enumerate(self.bgplvms): + ax = fig.add_subplot(1, len(self.bgplvms), i + 1) + g.plot_latent(ax=ax, *args, **kwargs) + pylab.draw() + fig.tight_layout() + return fig diff --git a/GPy/models/sparse_GP.py b/GPy/models/sparse_GP.py index 88abf77d..b816e684 100644 --- a/GPy/models/sparse_GP.py +++ b/GPy/models/sparse_GP.py @@ -36,7 +36,7 @@ class sparse_GP(GP): def __init__(self, X, likelihood, kernel, Z, X_variance=None, Xslices=None,Zslices=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.Zslices = Zslices self.Xslices = Xslices @@ -184,6 +184,12 @@ 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: + if self.likelihood.is_heteroscedastic: + self.scale_factor = max(100.,(self.psi2_beta_scaled.sum(0).max())) + print self.scale_factor + else: + self.scale_factor = np.sqrt(self.psi2.sum(0).mean()*self.likelihood.precision) self._computations() def _get_params(self): diff --git a/GPy/testing/mrd_tests.py b/GPy/testing/mrd_tests.py new file mode 100644 index 00000000..d90a7430 --- /dev/null +++ b/GPy/testing/mrd_tests.py @@ -0,0 +1,32 @@ +# Copyright (c) 2013, Max Zwiessele +# Licensed under the BSD 3-clause license (see LICENSE.txt) +''' +Created on 10 Apr 2013 + +@author: maxz +''' + +import unittest +import numpy as np +import GPy + +class MRDTests(unittest.TestCase): + + def test_gradients(self): + num_m = 3 + N, M, Q, D = 20, 8, 5, 50 + X = np.random.rand(N, Q) + + k = GPy.kern.linear(Q) + GPy.kern.bias(Q) + GPy.kern.white(Q) + K = k.K(X) + Ylist = [np.random.multivariate_normal(np.zeros(N), K, D).T for _ in range(num_m)] + + m = GPy.models.MRD(*Ylist, Q=Q, kernel=k, M=M) + m.ensure_default_constraints() + m.randomize() + + self.assertTrue(m.checkgrad()) + +if __name__ == "__main__": + print "Running unit tests, please be (very) patient..." + unittest.main()