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utils.py
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import numpy as np
import pickle as pkl
import networkx as nx
import scipy.sparse as sp
from scipy.sparse.linalg.eigen.arpack import eigsh
from evaluation import calc_cosine
import sys
import cPickle
import random
import os
seed = 1
random.seed(seed)
np.random.seed(seed)
def parse_index_file(filename):
"""Parse index file."""
index = []
for line in open(filename):
index.append(int(line.strip()))
return index
def sample_mask(idx, l):
"""Create mask."""
mask = np.zeros(l)
mask[idx] = 1
return np.array(mask, dtype=np.bool)
def load_wiki():
"""
train_img_feats:2173*4096
train_txt_vecs:2173*5000
train_labels:2173*1
test_txt_vecs:693*5000
test_img_feats:693*4096
test_labels:693*1
"""
with open('./data/wikipedia_dataset/train_img_feats.pkl', 'rb') as f:
train_img_feats = cPickle.load(f)
with open('./data/wikipedia_dataset/train_txt_vecs.pkl', 'rb') as f:
train_txt_vecs = cPickle.load(f)
with open('./data/wikipedia_dataset/train_labels_onehot.pkl', 'rb') as f:
train_labels = cPickle.load(f)
with open('./data/wikipedia_dataset/test_img_feats.pkl', 'rb') as f:
test_img_feats = cPickle.load(f)
with open('./data/wikipedia_dataset/test_txt_vecs.pkl', 'rb') as f:
test_txt_vecs = cPickle.load(f)
with open('./data/wikipedia_dataset/test_labels_onehot.pkl', 'rb') as f:
test_labels = cPickle.load(f)
train_img_feats = np.array(train_img_feats)
train_txt_vecs = np.array(train_txt_vecs)
train_labels = np.array(train_labels)
test_img_feats = np.array(test_img_feats)
test_txt_vecs = np.array(test_txt_vecs)
test_labels = np.array(test_labels)
return train_img_feats, train_txt_vecs, train_labels, test_img_feats, test_txt_vecs, test_labels
def load_Flickr():
"""
image:20015*224*224*3 train:16012 test:4003
tags:20015*1386
labels:20015*24
"""
SAVE_DIR = './data/Flickr-25k-relu/'
train_img_path = SAVE_DIR + 'train_img_feats.pkl'
train_txt_path = SAVE_DIR + 'train_bow.pkl'
train_labels_path = SAVE_DIR + 'train_labels.pkl'
test_img_path = SAVE_DIR + 'test_img_feats.pkl'
test_txt_path = SAVE_DIR + 'test_bow.pkl'
test_labels_path = SAVE_DIR + 'test_labels.pkl'
with open(train_img_path, 'rb') as f:
train_img_feats = cPickle.load(f)
with open(train_txt_path, 'rb') as f:
train_txt_vecs = cPickle.load(f)
with open(train_labels_path, 'rb') as f:
train_labels = cPickle.load(f)
with open(test_img_path, 'rb') as f:
test_img_feats = cPickle.load(f)
with open(test_txt_path, 'rb') as f:
test_txt_vecs = cPickle.load(f)
with open(test_labels_path, 'rb') as f:
test_labels = cPickle.load(f)
train_img_feats = np.array(train_img_feats)
train_txt_vecs = np.array(train_txt_vecs)
train_labels = np.array(train_labels)
test_img_feats = np.array(test_img_feats)
test_txt_vecs = np.array(test_txt_vecs)
test_labels = np.array(test_labels)
return train_img_feats, train_txt_vecs, train_labels, test_img_feats, test_txt_vecs, test_labels
def load_nuswide():
"""
load cross modal (img,txt) feature
:param dataset_str: dataset name
:return:
"""
with open('./data/nuswide/img_train_id_feats.pkl', 'rb') as f:
train_img_feats = cPickle.load(f)
with open('./data/nuswide/train_id_bow.pkl', 'rb') as f:
train_txt_vecs = cPickle.load(f)
with open('./data/nuswide/train_id_label_map.pkl', 'rb') as f:
train_labels = cPickle.load(f)
# load test data
with open('./data/nuswide/img_test_id_feats.pkl', 'rb') as f:
test_img_feats = cPickle.load(f)
with open('./data/nuswide/test_id_bow.pkl', 'rb') as f:
test_txt_vecs = cPickle.load(f)
with open('./data/nuswide/test_id_label_map.pkl', 'rb') as f:
test_labels = cPickle.load(f)
# index of trainging set and test set
# not equal to the index in training set,this index is shuffled
with open('./data/nuswide/train_ids.pkl', 'rb') as f:
train_ids = cPickle.load(f)
with open('./data/nuswide/test_ids.pkl', 'rb') as f:
test_ids = cPickle.load(f)
np.random.shuffle(train_ids)
np.random.shuffle(test_ids)
train_img_feats = [train_img_feats[i] for i in train_ids]
train_txt_vecs = [train_txt_vecs[i] for i in train_ids]
train_labels = [train_labels[i] for i in train_ids]
test_img_feats = [test_img_feats[i] for i in test_ids]
test_txt_vecs = [test_txt_vecs[i] for i in test_ids]
test_labels = [test_labels[i] for i in test_ids]
# train_img_feats = sp.csr_matrix(train_img_feats)
# train_txt_vecs = sp.csr_matrix(train_txt_vecs)
# train_labels = sp.csr_matrix(train_labels)
# test_img_feats = sp.csr_matrix(test_img_feats)
# test_txt_vecs = sp.csr_matrix(test_txt_vecs)
# test_labels = sp.csr_matrix(test_labels)
train_img_feats = np.array(train_img_feats)
train_txt_vecs = np.array(train_txt_vecs)
train_labels = np.array(train_labels)
test_img_feats = np.array(test_img_feats)
test_txt_vecs = np.array(test_txt_vecs)
test_labels = np.array(test_labels)
return train_img_feats, train_txt_vecs, train_labels, test_img_feats, test_txt_vecs, test_labels
def load_semi_nuswide(percentage):
"""
load cross modal (img,txt) feature
:param dataset_str: dataset name
:return:
"""
with open('./data/semi-nuswide/img_train_id_feats.pkl', 'rb') as f:
train_img_feats = cPickle.load(f)
with open('./data/semi-nuswide/train_id_bow.pkl', 'rb') as f:
train_txt_vecs = cPickle.load(f)
with open('./data/semi-nuswide/train_id_label_map.pkl', 'rb') as f:
train_labels = cPickle.load(f)
# load test data
with open('./data/semi-nuswide/img_test_id_feats.pkl', 'rb') as f:
test_img_feats = cPickle.load(f)
with open('./data/semi-nuswide/test_id_bow.pkl', 'rb') as f:
test_txt_vecs = cPickle.load(f)
with open('./data/semi-nuswide/test_id_label_map.pkl', 'rb') as f:
test_labels = cPickle.load(f)
# index of trainging set and test set
# not equal to the index in training set,this index is shuffled
with open('./data/semi-nuswide/train_ids.pkl', 'rb') as f:
train_ids = cPickle.load(f)
with open('./data/semi-nuswide/test_ids.pkl', 'rb') as f:
test_ids = cPickle.load(f)
np.random.shuffle(train_ids)
np.random.shuffle(test_ids)
train_img_feats = [train_img_feats[i] for i in train_ids]
train_txt_vecs = [train_txt_vecs[i] for i in train_ids]
train_labels = [train_labels[i] for i in train_ids]
test_img_feats = [test_img_feats[i] for i in test_ids]
test_txt_vecs = [test_txt_vecs[i] for i in test_ids]
test_labels = [test_labels[i] for i in test_ids]
train_img_feats = np.array(train_img_feats)
train_txt_vecs = np.array(train_txt_vecs)
train_labels = np.array(train_labels)
test_img_feats = np.array(test_img_feats)
test_txt_vecs = np.array(test_txt_vecs)
test_labels = np.array(test_labels)
num_train = train_img_feats.shape[0]
used_num = int(num_train * percentage)
train_img_feats = train_img_feats[:used_num, :]
train_txt_vecs = train_txt_vecs[:used_num, :]
train_labels = train_labels[:used_num, :]
return train_img_feats, train_txt_vecs, train_labels, test_img_feats, test_txt_vecs, test_labels
'''
use all labels to construct the graph but only use the train subgraph when trainning
'''
def compute_adj(dataset_str, train_labels, test_labels):
"""
:param dataset_str: dataset name
:param train_labels: train labels
:param test_labels: test labels
:return: csr_matrix
"""
data_path = 'data/' + dataset_str + '/cross_modal_adj' + '.pkl'
if os.path.exists(data_path):
with open(data_path, 'r') as f:
adj = cPickle.load(f)
return adj
else:
labels = np.vstack((train_labels, test_labels))
adj = np.dot(labels, np.transpose(labels))
sp_adj = sp.csr_matrix(adj, dtype=np.float32)
with open(data_path, 'w') as f:
cPickle.dump(sp_adj, f)
return adj
def compute_img_adj_semi(dataset_str, train, test, train_labels, label_percentage, threshold, semi_threshold=None):
"""
:param dataset_str: dataset name
:param train: train feature
:param test: test feature
:param train_labels: train labels
:param threshold: similarity threshold
:param semi_threshold: threshold for unlabeled data in training set
:param label_percentage: percentage of labeled data
:return: csr_matrix
"""
if semi_threshold is None:
data_path = 'data/' + dataset_str + '/img_adj_' + str(threshold) + '_' + str(label_percentage) + '.pkl'
else:
data_path = 'data/' + dataset_str + '/img_adj_' + str(threshold) + '_' + str(semi_threshold) + '_' + str(
label_percentage) + '.pkl'
if os.path.exists(data_path):
print('load img adj from : {}'.format(data_path))
with open(data_path, 'r') as f:
img_adj = cPickle.load(f)
return img_adj
else:
print('create img adj to :{}'.format(data_path))
len_train = len(train)
len_test = len(test)
labeled_num = int(len_train * label_percentage)
unlabeled_num = len_train - labeled_num
labeled_train_data = train[0:labeled_num, :]
used_label = train_labels[0:labeled_num]
unlabeled_train_data = train[labeled_num:, :]
shape = (len_test + len_train, len_test + len_train)
S_img = (np.dot(used_label, np.transpose(used_label)) > 0).astype(int)
img_adj = np.zeros(shape, dtype=np.float32)
img_adj[:labeled_num, :labeled_num] = S_img
for index in range(unlabeled_num):
temp = unlabeled_train_data[index]
dists = calc_cosine(labeled_train_data, temp)
sorted_idx = np.argsort(dists)
for k in range(semi_threshold):
img_adj[labeled_num + index][sorted_idx[k]] = 1
img_adj[sorted_idx[k]][labeled_num + index] = 1
print("process unlabeld: [{0}/{1}]".format(index, unlabeled_num))
for index in range(len_test):
temp = test[index]
dists = calc_cosine(labeled_train_data, temp)
sorted_idx = np.argsort(dists)
for k in range(threshold):
img_adj[len_train + index][sorted_idx[k]] = 1
img_adj[sorted_idx[k]][len_train + index] = 1
print("process test: [{0}/{1}]".format(index, len_test))
img_adj = sp.csr_matrix(img_adj, dtype=np.float32)
with open(data_path, 'w') as f:
cPickle.dump(img_adj, f)
return img_adj
def compute_txt_adj_semi(dataset_str, train, test, train_labels, label_percentage, threshold, semi_threshold=None):
"""
:param dataset_str: dataset name
:param train: train feature
:param test: test feature
:param train_labels: train labels
:param threshold: similarity threshold
:param semi_threshold: threshold for unlabeled data in training set
:param label_percentage: percentage of labeled data
:return: csr_matrix
"""
if semi_threshold is None:
data_path = 'data/' + dataset_str + '/txt_adj_' + str(threshold) + '_' + str(label_percentage) + '.pkl'
else:
data_path = 'data/' + dataset_str + '/txt_adj_' + str(threshold) + '_' + str(semi_threshold) + '_' + str(
label_percentage) + '.pkl'
if os.path.exists(data_path):
print('load txt adj from : {}'.format(data_path))
with open(data_path, 'r') as f:
txt_adj = cPickle.load(f)
return txt_adj
else:
print('create txt adj to :{}'.format(data_path))
len_train = len(train)
len_test = len(test)
labeled_num = int(len_train * label_percentage)
unlabeled_num = len_train - labeled_num
labeled_train_data = train[0:labeled_num, :]
used_label = train_labels[0:labeled_num]
unlabeled_train_data = train[labeled_num:, :]
shape = (len_test + len_train, len_test + len_train)
S_txt = (np.dot(used_label, np.transpose(used_label)) > 0).astype(int)
img_adj = np.zeros(shape, dtype=np.float32)
img_adj[:labeled_num, :labeled_num] = S_txt
for index in range(unlabeled_num):
temp = unlabeled_train_data[index]
dists = calc_cosine(labeled_train_data, temp)
sorted_idx = np.argsort(dists)
for k in range(semi_threshold):
img_adj[labeled_num + index][sorted_idx[k]] = 1
img_adj[sorted_idx[k]][labeled_num + index] = 1
print("process unlabeld: [{0}/{1}]".format(index, unlabeled_num))
for index in range(len_test):
temp = test[index]
dists = calc_cosine(labeled_train_data, temp)
sorted_idx = np.argsort(dists)
for k in range(threshold):
img_adj[len_train + index][sorted_idx[k]] = 1
img_adj[sorted_idx[k]][len_train + index] = 1
print("process test: [{0}/{1}]".format(index, len_test))
txt_adj = sp.csr_matrix(img_adj, dtype=np.float32)
with open(data_path, 'w') as f:
cPickle.dump(txt_adj, f)
return txt_adj
def compute_img_adj(dataset_str, train, test, train_labels, density):
"""
:param dataset_str: dataset name
:param train: train feature
:param test: test feature
:param train_labels: train labels
:param density: k most similar train data to test data
:return: csr_matrix
"""
data_path = 'data/'+dataset_str+'/img_adj_'+str(density)+'.pkl'
if os.path.exists(data_path):
with open(data_path,'r') as f:
img_adj = cPickle.load(f)
return img_adj
else:
# train = train.toarray()
# test = test.toarray()
# train_labels = train_labels.toarray()
len_train = len(train)
len_test = len(test)
shape = (len_test+len_train, len_test+len_train)
S_img = (np.dot(train_labels, np.transpose(train_labels)) > 0).astype(int)
img_adj = np.zeros(shape)
img_adj[:len_train, :len_train] = S_img
for index in range(len_test):
temp = test[index]
diffs = train - temp
dists = np.linalg.norm(diffs, axis=1)
sorted_idx = np.argsort(dists)
for k in range(density):
img_adj[sorted_idx[k]][len_train+index] = 1
img_adj[len_train + index][sorted_idx[k]] = 1
print("process: [{0}/{1}]".format(index, len_test))
img_adj = sp.csr_matrix(img_adj, dtype=np.int32)
with open(data_path,'w') as f:
cPickle.dump(img_adj,f)
return img_adj
def compute_txt_adj(dataset_str, train, test, train_labels, density):
"""
:param dataset_str: dataset name
:param train: train feature
:param test: test feature
:param train_labels: train labels
:param density: k most similar train data to test data
:return: csr_matrix
"""
data_path = 'data/'+dataset_str+'/txt_adj_'+str(density)+'.pkl'
if os.path.exists(data_path):
with open(data_path,'r') as f:
txt_adj = cPickle.load(f)
return txt_adj
else:
# train = train.toarray()
# test = test.toarray()
# train_labels = train_labels.toarray()
len_train = len(train)
len_test = len(test)
shape = (len_test+len_train, len_test+len_train)
S_txt = (np.dot(train_labels, np.transpose(train_labels)) > 0).astype(int)
txt_adj = np.zeros(shape)
txt_adj[:len_train, :len_train] = S_txt
train = np.array(train)
for index in range(len_test):
temp = test[index]
dists = -1 * np.dot(temp, train.transpose())
sorted_idx = np.argsort(dists)
for k in range(density):
txt_adj[sorted_idx[k]][len_train + index] = 1
txt_adj[len_train + index][sorted_idx[k]] = 1
print("process: [{0}/{1}]".format(index, len_test))
txt_adj = sp.csr_matrix(txt_adj, dtype=np.int32)
with open(data_path,'w') as f:
cPickle.dump(txt_adj,f)
return txt_adj
def load_data(dataset_str):
"""
Loads input data from gcn/data directory
ind.dataset_str.x => the feature vectors of the training instances as scipy.sparse.csr.csr_matrix object;
ind.dataset_str.tx => the feature vectors of the test instances as scipy.sparse.csr.csr_matrix object;
ind.dataset_str.allx => the feature vectors of both labeled and unlabeled training instances
(a superset of ind.dataset_str.x) as scipy.sparse.csr.csr_matrix object;
ind.dataset_str.y => the one-hot labels of the labeled training instances as numpy.ndarray object;
ind.dataset_str.ty => the one-hot labels of the test instances as numpy.ndarray object;
ind.dataset_str.ally => the labels for instances in ind.dataset_str.allx as numpy.ndarray object;
ind.dataset_str.graph => a dict in the format {index: [index_of_neighbor_nodes]} as collections.defaultdict
object;
ind.dataset_str.test.index => the indices of test instances in graph, for the inductive setting as list object.
All objects above must be saved using python pickle module.
:param dataset_str: Dataset name
:return: All data input files loaded (as well the training/test data).
"""
names = ['x', 'y', 'tx', 'ty', 'allx', 'ally', 'graph']
objects = []
for i in range(len(names)):
with open("data/ind.{}.{}".format(dataset_str, names[i]), 'rb') as f:
if sys.version_info > (3, 0):
objects.append(pkl.load(f, encoding='latin1'))
else:
objects.append(pkl.load(f))
x, y, tx, ty, allx, ally, graph = tuple(objects)
test_idx_reorder = parse_index_file("data/ind.{}.test.index".format(dataset_str))
test_idx_range = np.sort(test_idx_reorder)
if dataset_str == 'citeseer':
# Fix citeseer dataset (there are some isolated nodes in the graph)
# Find isolated nodes, add them as zero-vecs into the right position
test_idx_range_full = range(min(test_idx_reorder), max(test_idx_reorder)+1)
tx_extended = sp.lil_matrix((len(test_idx_range_full), x.shape[1]))
tx_extended[test_idx_range-min(test_idx_range), :] = tx
tx = tx_extended
ty_extended = np.zeros((len(test_idx_range_full), y.shape[1]))
ty_extended[test_idx_range-min(test_idx_range), :] = ty
ty = ty_extended
features = sp.vstack((allx, tx)).tolil()
features[test_idx_reorder, :] = features[test_idx_range, :]
adj = nx.adjacency_matrix(nx.from_dict_of_lists(graph))
labels = np.vstack((ally, ty))
labels[test_idx_reorder, :] = labels[test_idx_range, :]
idx_test = test_idx_range.tolist()
idx_train = range(len(y))
idx_val = range(len(y), len(y)+500)
train_mask = sample_mask(idx_train, labels.shape[0])
val_mask = sample_mask(idx_val, labels.shape[0])
test_mask = sample_mask(idx_test, labels.shape[0])
y_train = np.zeros(labels.shape)
y_val = np.zeros(labels.shape)
y_test = np.zeros(labels.shape)
y_train[train_mask, :] = labels[train_mask, :]
y_val[val_mask, :] = labels[val_mask, :]
y_test[test_mask, :] = labels[test_mask, :]
return adj, features, y_train, y_val, y_test, train_mask, val_mask, test_mask
def sparse_to_tuple(sparse_mx):
"""Convert sparse matrix to tuple representation."""
def to_tuple(mx):
if not sp.isspmatrix_coo(mx):
mx = mx.tocoo()
coords = np.vstack((mx.row, mx.col)).transpose()
values = mx.data
shape = mx.shape
return coords, values, shape
if isinstance(sparse_mx, list):
for i in range(len(sparse_mx)):
sparse_mx[i] = to_tuple(sparse_mx[i])
else:
sparse_mx = to_tuple(sparse_mx)
return sparse_mx
def preprocess_features(features):
"""Row-normalize feature matrix and convert to tuple representation"""
rowsum = np.array(features.sum(1))
r_inv = np.power(rowsum, -1).flatten()
r_inv[np.isinf(r_inv)] = 0.
r_mat_inv = sp.diags(r_inv)
features = r_mat_inv.dot(features)
return sparse_to_tuple(features)
def normalize_adj(adj):
"""Symmetrically normalize adjacency matrix."""
adj = sp.coo_matrix(adj)
rowsum = np.array(adj.sum(1))
d_inv_sqrt = np.power(rowsum, -0.5).flatten()
d_inv_sqrt[np.isinf(d_inv_sqrt)] = 0.
d_mat_inv_sqrt = sp.diags(d_inv_sqrt)
return adj.dot(d_mat_inv_sqrt).transpose().dot(d_mat_inv_sqrt).tocoo()
def preprocess_adj(adj):
"""Preprocessing of adjacency matrix for simple GCN model and conversion to tuple representation."""
adj_normalized = normalize_adj(adj + sp.eye(adj.shape[0]))
return sparse_to_tuple(adj_normalized)
def preprocess_adj_dense(adj):
"""Preprocessing of adjacency matrix for simple GCN model and adj is not sparse"""
adj_normalized = normalize_adj(adj + np.eye(adj.shape[0]))
return adj_normalized.toarray()
def construct_feed_dict(img_feature, txt_feature, img_support, txt_support, placeholders):
"""Construct feed dictionary."""
feed_dict = dict()
feed_dict.update({placeholders['img_feature']: img_feature})
feed_dict.update({placeholders['txt_feature']: txt_feature})
feed_dict.update({placeholders['img_support']: img_support})
feed_dict.update({placeholders['txt_support']: txt_support})
return feed_dict
def chebyshev_polynomials(adj, k):
"""Calculate Chebyshev polynomials up to order k. Return a list of sparse matrices (tuple representation)."""
print("Calculating Chebyshev polynomials up to order {}...".format(k))
adj_normalized = normalize_adj(adj)
laplacian = sp.eye(adj.shape[0]) - adj_normalized
largest_eigval, _ = eigsh(laplacian, 1, which='LM')
scaled_laplacian = (2. / largest_eigval[0]) * laplacian - sp.eye(adj.shape[0])
t_k = list()
t_k.append(sp.eye(adj.shape[0]))
t_k.append(scaled_laplacian)
def chebyshev_recurrence(t_k_minus_one, t_k_minus_two, scaled_lap):
s_lap = sp.csr_matrix(scaled_lap, copy=True)
return 2 * s_lap.dot(t_k_minus_one) - t_k_minus_two
for i in range(2, k+1):
t_k.append(chebyshev_recurrence(t_k[-1], t_k[-2], scaled_laplacian))
return sparse_to_tuple(t_k)