PyTorch 中的史丹佛汽車

data
 └-stanford_cars
    |-cars_test_annos_withlabels.mat
    |-cars_test
    |  └-*.jpg
    |-cars_train
    |  └-*.jpg
    └-devkit
       |-cars_meta.mat
       |-cars_test_annos.mat
       |-cars_train_annos.mat
       |-eval_train.m
       |-README.txt
       └-train_perfect_preds.txt

from torchvision.datasets import StanfordCars

train_data = StanfordCars(
    root="data"
)

train_data = StanfordCars(
    root="data",
    split="train",
    transform=None,
    target_transform=None,
    download=False
)

test_data = StanfordCars(
    root="data",
    split="test"
)

len(train_data), len(test_data)
# (8144, 8041)

train_data
# Dataset StanfordCars
#     Number of datapoints: 8144
#     Root location: data

train_data.root
# 'data'

train_data._split
# 'train'

print(train_data.transform)
# None

print(train_data.target_transform)
# None

train_data.download
# <bound method StanfordCars.download of Dataset StanfordCars
#     Number of datapoints: 8144
#     Root location: data>

len(train_data.classes), train_data.classes
# (196,
#  ['AM General Hummer SUV 2000', 'Acura RL Sedan 2012', 'Acura TL Sedan 2012',
#   'Acura TL Type-S 2008', ..., 'Volvo 240 Sedan 1993',
#   'Volvo XC90 SUV 2007', 'smart fortwo Convertible 2012'])

train_data[0]
# (<PIL.Image.Image image mode=RGB size=600x400>, 13)

train_data[1]
# (<PIL.Image.Image image mode=RGB size=900x675>, 2)

train_data[2]
# (<PIL.Image.Image image mode=RGB size=640x480>, 90)

train_data[3]
# (<PIL.Image.Image image mode=RGB size=2100x1386>, 133)

train_data[4]
# (<PIL.Image.Image image mode=RGB size=144x108>, 105)

import matplotlib.pyplot as plt

def show_images(data, main_title=None):
    plt.figure(figsize=(12, 5))
    plt.suptitle(t=main_title, y=1.0, fontsize=14)
    for i, (im, lab) in zip(range(1, 11), data):
        plt.subplot(2, 5, i)
        plt.imshow(X=im)
        plt.title(label=lab)
    plt.tight_layout()
    plt.show()

show_images(data=train_data, main_title="train_data")
show_images(data=test_data, main_title="test_data")

show_images(data=train_data, ims=train_ims, main_title="train_data")
show_images(data=train_data, ims=val_ims, main_title="val_data")
show_images(data=test_data, ims=test_ims, main_title="test_data")