一、DataLoader參數解析

DataLoader官網使用手冊

參數	描述
dataset	說明數據集所在的位置、數據總數等
batch_size	每次取多少張圖片
shuffle	True亂序、False順序(默認)
sampler
batch_sampler
num_workers	多進程，默認為0采用主進程加載數據
collate_fn
pin_memory
drop_last	True最后不滿一個batch_size的去掉，False最后剩余多少也都要
timeout
worker_init_fn
generator
prefetch_factor
prefetch_factor
pin_memory_device

import torchvision
from torch.utils.data import DataLoader
from torch.utils.tensorboard import SummaryWritertest_data = torchvision.datasets.CIFAR10("CIFAR_10",train=False,transform=torchvision.transforms.ToTensor())
#Ctrl按住，點擊CIFAR10，找到__getitem__類，查看返回值return img, targettest_loader = DataLoader(dataset=test_data,batch_size=64,shuffle=True,num_workers=0,drop_last=False)
#drop_last=False，最后剩余多少也都要 
#shuffle=True，亂序#測試一下
img,target = test_data[0]
print(img.shape)#torch.Size([3, 32, 32])
print(target)#3writer = SummaryWriter("y_log")
i = 0
for data in test_loader:imgs,targets = data#print(type(imgs))writer.add_images("test_data",imgs,i)i = i+1writer.close()

在Terminal下運行tensorboard --logdir=y_log --port=2312，logdir為打開事件文件的路徑，port為指定端口打開；
通過指定端口2312進行打開tensorboard，若不設置port參數，默認通過6006端口進行打開。

點擊該鏈接或者復制鏈接到瀏覽器打開即可

import torchvision
from torch.utils.data import DataLoader
from torch.utils.tensorboard import SummaryWritertest_data = torchvision.datasets.CIFAR10("CIFAR_10",train=False,transform=torchvision.transforms.ToTensor())
#Ctrl按住，點擊CIFAR10，找到__getitem__類，查看返回值return img, targettest_loader = DataLoader(dataset=test_data,batch_size=64,shuffle=False,num_workers=0,drop_last=True)
#drop_last=True，不滿一組的舍去 
#shuffle=False，順序img,target = test_data[0]
print(img.shape)#torch.Size([3, 32, 32])
print(target)#3writer = SummaryWriter("y_log")for epoch in range(3):i = 0for data in test_loader:imgs,targets = data#print(type(imgs))writer.add_images("Epoch:{}".format(epoch),imgs,i)i = i+1writer.close()