标签：file nump form 处理 lambda item cal rda col
给出ImageFolderDataset类的描述，
Init signature: mxnet.gluon.data.vision.datasets.ImageFolderDataset(root, flag=1, transform=None)
Source:
class ImageFolderDataset(dataset.Dataset):
"""A dataset for loading image files stored in a folder structure like::
root/car/0001.jpg
root/car/xxxa.jpg
root/car/yyyb.jpg
root/bus/123.jpg
root/bus/023.jpg
root/bus/wwww.jpg
Parameters
----------
root : str
Path to root directory.
flag : {0, 1}, default 1 # 控制彩色or灰度
If 0, always convert loaded images to greyscale (1 channel).
If 1, always convert loaded images to colored (3 channels).
transform : callable, default None
A function that takes data and label and transforms them:
::
transform = lambda data, label: (data.astype(np.float32)/255, label)
Attributes
----------
synsets : list # 查看类别，实际就是文件名
List of class names. `synsets[i]` is the name for the integer label `i`
items : list of tuples # 生成的数据
List of all images in (filename, label) pairs.
"""
实例：
train_imgs = gluon.data.vision.ImageFolderDataset(
data_dir+‘/hotdog/train‘,
transform=lambda X, y: transform(X, y, train_augs))
test_imgs = gluon.data.vision.ImageFolderDataset(
data_dir+‘/hotdog/test‘,
transform=lambda X, y: transform(X, y, test_augs))
print(train_imgs)
print(train_imgs.synsets)
data = gluon.data.DataLoader(train_imgs, 32, shuffle=True)
<mxnet.gluon.data.vision.datasets.ImageFolderDataset object at 0x7fbed5641c18> [‘hotdog‘, ‘not-hotdog‘]
具有特殊方法，def __iter__(self)，其实例可以被迭代，也就是每次返回一个batch的数据，在第一维度上切割。
首个定位参数文档如下：
dataset : Dataset
Source dataset. Note that numpy and mxnet arrays can be directly used
as a Dataset.
最后生成的X_batch送入net(X_batch)向前传播，y_batch送入loss(output,y_batch)计算loss后反向传播。
https://blog.csdn.net/qq_36165459/article/details/78394322
https://blog.csdn.net/u012759136/article/details/50208733#%E4%BA%8C%E4%BB%8E%E5%8E%9F%E7%94%9F%E6%95%B0%E6%8D%AE%E7%94%9F%E6%88%90lst%E6%96%87%E4%BB%B6
标签：file nump form 处理 lambda item cal rda col
原文地址：https://www.cnblogs.com/hellcat/p/9094806.html
