From 4cb6986480def9b0c91fb46e276839c60f96aa49 Mon Sep 17 00:00:00 2001 From: Yigit Sever Date: Sat, 21 Sep 2019 15:06:32 +0300 Subject: Tidy up Wasserstein classes into one file --- Wass_Retriever.py | 73 ------------------------------------------------------- 1 file changed, 73 deletions(-) delete mode 100644 Wass_Retriever.py (limited to 'Wass_Retriever.py') diff --git a/Wass_Retriever.py b/Wass_Retriever.py deleted file mode 100644 index 036cf93..0000000 --- a/Wass_Retriever.py +++ /dev/null @@ -1,73 +0,0 @@ -import ot -from sklearn.preprocessing import normalize -from sklearn.neighbors import KNeighborsClassifier -from sklearn.metrics import euclidean_distances -from sklearn.externals.joblib import Parallel, delayed -from sklearn.utils import check_array -from sklearn.metrics.scorer import check_scoring -from pathos.multiprocessing import ProcessingPool as Pool -from sklearn.metrics import euclidean_distances -import numpy as np - -class Wasserstein_Retriever(KNeighborsClassifier): - """ - Implements a nearest neighbors classifier for input distributions using the Wasserstein distance as metric. - Source and target distributions are l_1 normalized before computing the Wasserstein distance. - Wasserstein is parametrized by the distances between the individual points of the distributions. - """ - def __init__(self, W_embed, n_neighbors=1, n_jobs=1, verbose=False, sinkhorn= False, sinkhorn_reg=0.1): - """ - Initialization of the class. - Arguments - --------- - W_embed: embeddings of the words, np.array - verbose: True/False - """ - self.sinkhorn = sinkhorn - self.sinkhorn_reg = sinkhorn_reg - self.W_embed = W_embed - self.verbose = verbose - super(Wasserstein_Retriever, self).__init__(n_neighbors=n_neighbors, n_jobs=n_jobs, metric='precomputed', algorithm='brute') - - def _wmd(self, i, row, X_train): - union_idx = np.union1d(X_train[i].indices, row.indices) - W_minimal = self.W_embed[union_idx] - W_dist = euclidean_distances(W_minimal) - bow_i = X_train[i, union_idx].A.ravel() - bow_j = row[:, union_idx].A.ravel() - if self.sinkhorn: - return ot.sinkhorn2(bow_i, bow_j, W_dist, self.sinkhorn_reg, numItermax=50, method='sinkhorn_stabilized',)[0] - else: - return ot.emd2(bow_i, bow_j, W_dist) - - def _wmd_row(self, row): - X_train = self._fit_X - n_samples_train = X_train.shape[0] - return [self._wmd(i, row, X_train) for i in range(n_samples_train)] - - def _pairwise_wmd(self, X_test, X_train=None): - n_samples_test = X_test.shape[0] - - if X_train is None: - X_train = self._fit_X - pool = Pool(nodes=self.n_jobs) # Parallelization of the calculation of the distances - dist = pool.map(self._wmd_row, X_test) - return np.array(dist) - - def fit(self, X, y): - X = check_array(X, accept_sparse='csr', copy=True) - X = normalize(X, norm='l1', copy=False) - return super(Wasserstein_Retriever, self).fit(X, y) - - def predict(self, X): - X = check_array(X, accept_sparse='csr', copy=True) - X = normalize(X, norm='l1', copy=False) - dist = self._pairwise_wmd(X) - return super(Wasserstein_Retriever, self).predict(dist) - - def kneighbors(self, X, n_neighbors=1): - X = check_array(X, accept_sparse='csr', copy=True) - X = normalize(X, norm='l1', copy=False) - dist = self._pairwise_wmd(X) - return super(Wasserstein_Retriever, self).kneighbors(dist, n_neighbors) - -- cgit v1.2.3-70-g09d2