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author | Rémi Flamary <remi.flamary@gmail.com> | 2020-04-20 22:04:03 +0200 |
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committer | Rémi Flamary <remi.flamary@gmail.com> | 2020-04-20 22:04:03 +0200 |
commit | 21949bbc3469234f88972bdfe973f68eb9e62794 (patch) | |
tree | 6bc93db587bd80d0ccb9e33596c4526aeaefec4c /ot | |
parent | d54184c233cd211a693e4cdf4b25dd68b07ed00b (diff) | |
parent | 43b2190db71b1ccbeec8fddaae23ca6af220e1b5 (diff) |
Merge branch 'master' into doc_travis
Diffstat (limited to 'ot')
-rw-r--r-- | ot/da.py | 253 | ||||
-rw-r--r-- | ot/utils.py | 6 |
2 files changed, 258 insertions, 1 deletions
@@ -16,7 +16,7 @@ import scipy.linalg as linalg from .bregman import sinkhorn, jcpot_barycenter from .lp import emd -from .utils import unif, dist, kernel, cost_normalization, label_normalization +from .utils import unif, dist, kernel, cost_normalization, label_normalization, laplacian, dots from .utils import check_params, BaseEstimator from .unbalanced import sinkhorn_unbalanced from .optim import cg @@ -748,6 +748,139 @@ def OT_mapping_linear(xs, xt, reg=1e-6, ws=None, return A, b +def emd_laplace(a, b, xs, xt, M, sim='knn', sim_param=None, reg='pos', eta=1, alpha=.5, + numItermax=100, stopThr=1e-9, numInnerItermax=100000, + stopInnerThr=1e-9, log=False, verbose=False): + r"""Solve the optimal transport problem (OT) with Laplacian regularization + + .. math:: + \gamma = arg\min_\gamma <\gamma,M>_F + eta\Omega_\alpha(\gamma) + + s.t.\ \gamma 1 = a + + \gamma^T 1= b + + \gamma\geq 0 + + where: + + - a and b are source and target weights (sum to 1) + - xs and xt are source and target samples + - M is the (ns,nt) metric cost matrix + - :math:`\Omega_\alpha` is the Laplacian regularization term + :math:`\Omega_\alpha = (1-\alpha)/n_s^2\sum_{i,j}S^s_{i,j}\|T(\mathbf{x}^s_i)-T(\mathbf{x}^s_j)\|^2+\alpha/n_t^2\sum_{i,j}S^t_{i,j}^'\|T(\mathbf{x}^t_i)-T(\mathbf{x}^t_j)\|^2` + with :math:`S^s_{i,j}, S^t_{i,j}` denoting source and target similarity matrices and :math:`T(\cdot)` being a barycentric mapping + + The algorithm used for solving the problem is the conditional gradient algorithm as proposed in [5]. + + Parameters + ---------- + a : np.ndarray (ns,) + samples weights in the source domain + b : np.ndarray (nt,) + samples weights in the target domain + xs : np.ndarray (ns,d) + samples in the source domain + xt : np.ndarray (nt,d) + samples in the target domain + M : np.ndarray (ns,nt) + loss matrix + sim : string, optional + Type of similarity ('knn' or 'gauss') used to construct the Laplacian. + sim_param : int or float, optional + Parameter (number of the nearest neighbors for sim='knn' + or bandwidth for sim='gauss') used to compute the Laplacian. + reg : string + Type of Laplacian regularization + eta : float + Regularization term for Laplacian regularization + alpha : float + Regularization term for source domain's importance in regularization + numItermax : int, optional + Max number of iterations + stopThr : float, optional + Stop threshold on error (inner emd solver) (>0) + numInnerItermax : int, optional + Max number of iterations (inner CG solver) + stopInnerThr : float, optional + Stop threshold on error (inner CG solver) (>0) + verbose : bool, optional + Print information along iterations + log : bool, optional + record log if True + + Returns + ------- + gamma : (ns x nt) ndarray + Optimal transportation matrix for the given parameters + log : dict + log dictionary return only if log==True in parameters + + + References + ---------- + + .. [5] N. Courty; R. Flamary; D. Tuia; A. Rakotomamonjy, + "Optimal Transport for Domain Adaptation," in IEEE + Transactions on Pattern Analysis and Machine Intelligence , + vol.PP, no.99, pp.1-1 + .. [30] R. Flamary, N. Courty, D. Tuia, A. Rakotomamonjy, + "Optimal transport with Laplacian regularization: Applications to domain adaptation and shape matching," + in NIPS Workshop on Optimal Transport and Machine Learning OTML, 2014. + + See Also + -------- + ot.lp.emd : Unregularized OT + ot.optim.cg : General regularized OT + + """ + if not isinstance(sim_param, (int, float, type(None))): + raise ValueError( + 'Similarity parameter should be an int or a float. Got {type} instead.'.format(type=type(sim_param).__name__)) + + if sim == 'gauss': + if sim_param is None: + sim_param = 1 / (2 * (np.mean(dist(xs, xs, 'sqeuclidean')) ** 2)) + sS = kernel(xs, xs, method=sim, sigma=sim_param) + sT = kernel(xt, xt, method=sim, sigma=sim_param) + + elif sim == 'knn': + if sim_param is None: + sim_param = 3 + + from sklearn.neighbors import kneighbors_graph + + sS = kneighbors_graph(X=xs, n_neighbors=int(sim_param)).toarray() + sS = (sS + sS.T) / 2 + sT = kneighbors_graph(xt, n_neighbors=int(sim_param)).toarray() + sT = (sT + sT.T) / 2 + else: + raise ValueError('Unknown similarity type {sim}. Currently supported similarity types are "knn" and "gauss".'.format(sim=sim)) + + lS = laplacian(sS) + lT = laplacian(sT) + + def f(G): + return alpha * np.trace(np.dot(xt.T, np.dot(G.T, np.dot(lS, np.dot(G, xt))))) \ + + (1 - alpha) * np.trace(np.dot(xs.T, np.dot(G, np.dot(lT, np.dot(G.T, xs))))) + + ls2 = lS + lS.T + lt2 = lT + lT.T + xt2 = np.dot(xt, xt.T) + + if reg == 'disp': + Cs = -eta * alpha / xs.shape[0] * dots(ls2, xs, xt.T) + Ct = -eta * (1 - alpha) / xt.shape[0] * dots(xs, xt.T, lt2) + M = M + Cs + Ct + + def df(G): + return alpha * np.dot(ls2, np.dot(G, xt2))\ + + (1 - alpha) * np.dot(xs, np.dot(xs.T, np.dot(G, lt2))) + + return cg(a, b, M, reg=eta, f=f, df=df, G0=None, numItermax=numItermax, numItermaxEmd=numInnerItermax, + stopThr=stopThr, stopThr2=stopInnerThr, verbose=verbose, log=log) + + def distribution_estimation_uniform(X): """estimates a uniform distribution from an array of samples X @@ -1576,6 +1709,124 @@ class SinkhornLpl1Transport(BaseTransport): return self +class EMDLaplaceTransport(BaseTransport): + + """Domain Adapatation OT method based on Earth Mover's Distance with Laplacian regularization + + Parameters + ---------- + reg_type : string optional (default='pos') + Type of the regularization term: 'pos' and 'disp' for + regularization term defined in [2] and [6], respectively. + reg_lap : float, optional (default=1) + Laplacian regularization parameter + reg_src : float, optional (default=0.5) + Source relative importance in regularization + metric : string, optional (default="sqeuclidean") + The ground metric for the Wasserstein problem + norm : string, optional (default=None) + If given, normalize the ground metric to avoid numerical errors that + can occur with large metric values. + similarity : string, optional (default="knn") + The similarity to use either knn or gaussian + similarity_param : int or float, optional (default=None) + Parameter for the similarity: number of nearest neighbors or bandwidth + if similarity="knn" or "gaussian", respectively. If None is provided, + it is set to 3 or the average pairwise squared Euclidean distance, respectively. + max_iter : int, optional (default=100) + Max number of BCD iterations + tol : float, optional (default=1e-5) + Stop threshold on relative loss decrease (>0) + max_inner_iter : int, optional (default=10) + Max number of iterations (inner CG solver) + inner_tol : float, optional (default=1e-6) + Stop threshold on error (inner CG solver) (>0) + log : int, optional (default=False) + Controls the logs of the optimization algorithm + distribution_estimation : callable, optional (defaults to the uniform) + The kind of distribution estimation to employ + out_of_sample_map : string, optional (default="ferradans") + The kind of out of sample mapping to apply to transport samples + from a domain into another one. Currently the only possible option is + "ferradans" which uses the method proposed in [6]. + + Attributes + ---------- + coupling_ : array-like, shape (n_source_samples, n_target_samples) + The optimal coupling + + References + ---------- + .. [1] N. Courty; R. Flamary; D. Tuia; A. Rakotomamonjy, + "Optimal Transport for Domain Adaptation," in IEEE Transactions + on Pattern Analysis and Machine Intelligence , vol.PP, no.99, pp.1-1 + .. [2] R. Flamary, N. Courty, D. Tuia, A. Rakotomamonjy, + "Optimal transport with Laplacian regularization: Applications to domain adaptation and shape matching," + in NIPS Workshop on Optimal Transport and Machine Learning OTML, 2014. + """ + + def __init__(self, reg_type='pos', reg_lap=1., reg_src=1., metric="sqeuclidean", + norm=None, similarity="knn", similarity_param=None, max_iter=100, tol=1e-9, + max_inner_iter=100000, inner_tol=1e-9, log=False, verbose=False, + distribution_estimation=distribution_estimation_uniform, + out_of_sample_map='ferradans'): + self.reg = reg_type + self.reg_lap = reg_lap + self.reg_src = reg_src + self.metric = metric + self.norm = norm + self.similarity = similarity + self.sim_param = similarity_param + self.max_iter = max_iter + self.tol = tol + self.max_inner_iter = max_inner_iter + self.inner_tol = inner_tol + self.log = log + self.verbose = verbose + self.distribution_estimation = distribution_estimation + self.out_of_sample_map = out_of_sample_map + + def fit(self, Xs, ys=None, Xt=None, yt=None): + """Build a coupling matrix from source and target sets of samples + (Xs, ys) and (Xt, yt) + + Parameters + ---------- + Xs : array-like, shape (n_source_samples, n_features) + The training input samples. + ys : array-like, shape (n_source_samples,) + The class labels + Xt : array-like, shape (n_target_samples, n_features) + The training input samples. + yt : array-like, shape (n_target_samples,) + The class labels. If some target samples are unlabeled, fill the + yt's elements with -1. + + Warning: Note that, due to this convention -1 cannot be used as a + class label + + Returns + ------- + self : object + Returns self. + """ + + super(EMDLaplaceTransport, self).fit(Xs, ys, Xt, yt) + + returned_ = emd_laplace(a=self.mu_s, b=self.mu_t, xs=self.xs_, + xt=self.xt_, M=self.cost_, sim=self.similarity, sim_param=self.sim_param, reg=self.reg, eta=self.reg_lap, + alpha=self.reg_src, numItermax=self.max_iter, stopThr=self.tol, numInnerItermax=self.max_inner_iter, + stopInnerThr=self.inner_tol, log=self.log, verbose=self.verbose) + + # coupling estimation + if self.log: + self.coupling_, self.log_ = returned_ + else: + self.coupling_ = returned_ + self.log_ = dict() + return self + + class SinkhornL1l2Transport(BaseTransport): """Domain Adapatation OT method based on sinkhorn algorithm + diff --git a/ot/utils.py b/ot/utils.py index c154f99..f9911a1 100644 --- a/ot/utils.py +++ b/ot/utils.py @@ -49,6 +49,12 @@ def kernel(x1, x2, method='gaussian', sigma=1, **kwargs): return K +def laplacian(x): + """Compute Laplacian matrix""" + L = np.diag(np.sum(x, axis=0)) - x + return L + + def unif(n): """ return a uniform histogram of length n (simplex) |