Files
dgl/examples/mxnet/gin/dataloader.py
Hongzhi (Steve), Chen 704bcaf6dd examples (#5323)
Co-authored-by: Ubuntu <ubuntu@ip-172-31-28-63.ap-northeast-1.compute.internal>
2023-02-19 08:35:15 +08:00

119 lines
3.3 KiB
Python

"""
MxNet compatible dataloader
"""
import math
import dgl
import numpy as np
from mxnet import nd
from mxnet.gluon.data import DataLoader, Sampler
from sklearn.model_selection import StratifiedKFold
class SubsetRandomSampler(Sampler):
def __init__(self, indices):
self.indices = indices
def __iter__(self):
return iter(
[self.indices[i] for i in np.random.permutation(len(self.indices))]
)
def __len__(self):
return len(self.indices)
# default collate function
def collate(samples):
# The input `samples` is a list of pairs (graph, label).
graphs, labels = map(list, zip(*samples))
for g in graphs:
# deal with node feats
for key in g.node_attr_schemes().keys():
g.ndata[key] = nd.array(g.ndata[key])
# no edge feats
batched_graph = dgl.batch(graphs)
labels = [nd.reshape(label, (1,)) for label in labels]
labels = nd.concat(*labels, dim=0)
return batched_graph, labels
class GraphDataLoader:
def __init__(
self,
dataset,
batch_size,
collate_fn=collate,
seed=0,
shuffle=True,
split_name="fold10",
fold_idx=0,
split_ratio=0.7,
):
self.shuffle = shuffle
self.seed = seed
labels = [l for _, l in dataset]
if split_name == "fold10":
train_idx, valid_idx = self._split_fold10(
labels, fold_idx, seed, shuffle
)
elif split_name == "rand":
train_idx, valid_idx = self._split_rand(
labels, split_ratio, seed, shuffle
)
else:
raise NotImplementedError()
train_sampler = SubsetRandomSampler(train_idx)
valid_sampler = SubsetRandomSampler(valid_idx)
self.train_loader = DataLoader(
dataset,
sampler=train_sampler,
batch_size=batch_size,
batchify_fn=collate_fn,
)
self.valid_loader = DataLoader(
dataset,
sampler=valid_sampler,
batch_size=batch_size,
batchify_fn=collate_fn,
)
def train_valid_loader(self):
return self.train_loader, self.valid_loader
def _split_fold10(self, labels, fold_idx=0, seed=0, shuffle=True):
"""10 flod"""
assert 0 <= fold_idx and fold_idx < 10, print(
"fold_idx must be from 0 to 9."
)
skf = StratifiedKFold(n_splits=10, shuffle=shuffle, random_state=seed)
idx_list = []
for idx in skf.split(
np.zeros(len(labels)), [label.asnumpy() for label in labels]
): # split(x, y)
idx_list.append(idx)
train_idx, valid_idx = idx_list[fold_idx]
print("train_set : test_set = %d : %d", len(train_idx), len(valid_idx))
return train_idx, valid_idx
def _split_rand(self, labels, split_ratio=0.7, seed=0, shuffle=True):
num_entries = len(labels)
indices = list(range(num_entries))
np.random.seed(seed)
np.random.shuffle(indices)
split = int(math.floor(split_ratio * num_entries))
train_idx, valid_idx = indices[:split], indices[split:]
print("train_set : test_set = %d : %d", len(train_idx), len(valid_idx))
return train_idx, valid_idx