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| 1 | +# -*- coding: utf-8 -*- |
| 2 | +# Author: XuMing <[email protected]> |
| 3 | +# Brief: http://pytorch.org/tutorials/beginner/blitz/cifar10_tutorial.html |
| 4 | +import torch |
| 5 | +import torchvision |
| 6 | +import torchvision.transforms as transforms |
| 7 | +import os |
| 8 | + |
| 9 | +data_dir = './data' |
| 10 | +if not os.path.exists(data_dir): |
| 11 | + os.makedirs(data_dir) |
| 12 | +transform = transforms.Compose([transforms.ToTensor(), |
| 13 | + transforms.Normalize((0.5, 0.5, 0.5), (0.5, 0.5, 0.5))]) |
| 14 | +train_set = torchvision.datasets.CIFAR10(root='./data', train=True, |
| 15 | + download=True, transform=transform) |
| 16 | +train_loader = torch.utils.data.DataLoader(train_set, batch_size=4, |
| 17 | + shuffle=True, num_workers=2) |
| 18 | +test_set = torchvision.datasets.CIFAR10(root='./data', train=False, |
| 19 | + download=True, transform=transform) |
| 20 | +test_loader = torch.utils.data.DataLoader(test_set, batch_size=4, |
| 21 | + shuffle=False, num_workers=2) |
| 22 | +classes = ('plane', 'car', 'bird' 'cat', |
| 23 | + 'deer', 'dog', 'frog', 'horse', 'ship', 'truck') |
| 24 | + |
| 25 | +import matplotlib.pyplot as plt |
| 26 | +import numpy as np |
| 27 | + |
| 28 | + |
| 29 | +def imshow(img): |
| 30 | + img = img / 2 + 0.5 |
| 31 | + npimg = img.numpy() |
| 32 | + plt.imshow(np.transpose(npimg, (1, 2, 0))) |
| 33 | + plt.show() |
| 34 | + |
| 35 | + |
| 36 | +data_iter = iter(train_loader) |
| 37 | +images, labels = data_iter.next() |
| 38 | + |
| 39 | +# show images |
| 40 | +imshow(torchvision.utils.make_grid(images)) |
| 41 | +print(' '.join('%s' % classes[labels[i]] for i in range(4))) |
| 42 | + |
| 43 | +# CNN |
| 44 | +from torch.autograd import Variable |
| 45 | +import torch.nn as nn |
| 46 | +import torch.nn.functional as F |
| 47 | +import torch.optim as optim |
| 48 | + |
| 49 | + |
| 50 | +class Network(nn.Module): |
| 51 | + def __init__(self): |
| 52 | + super(Network, self).__init__() |
| 53 | + self.conv1 = nn.Conv2d(3, 6, 5) |
| 54 | + self.pool = nn.MaxPool2d(2, 2) |
| 55 | + self.conv2 = nn.Conv2d(6, 16, 5) |
| 56 | + self.fc1 = nn.Linear(16 * 5 * 5, 120) |
| 57 | + self.fc2 = nn.Linear(120, 84) |
| 58 | + self.fc3 = nn.Linear(84, 10) |
| 59 | + |
| 60 | + def forward(self, x): |
| 61 | + x = self.pool(F.relu(self.conv1(x))) |
| 62 | + x = self.pool(F.relu(self.conv2(x))) |
| 63 | + x = x.view(-1, 16 * 5 * 5) |
| 64 | + x = F.relu(self.fc1(x)) |
| 65 | + x = F.relu(self.fc2(x)) |
| 66 | + x = self.fc3(x) |
| 67 | + return x |
| 68 | + |
| 69 | + |
| 70 | +criterion = nn.CrossEntropyLoss() |
| 71 | +network = Network() |
| 72 | +optimizer = optim.SGD(network.parameters(), lr=0.001, momentum=0.9) |
| 73 | +# train |
| 74 | +for epoch in range(1): |
| 75 | + running_loss = 0.0 |
| 76 | + for i, data in enumerate(train_loader, 0): |
| 77 | + inputs, labels = data |
| 78 | + inputs, labels = Variable(inputs), Variable(labels) |
| 79 | + optimizer.zero_grad() |
| 80 | + outputs = network(inputs) |
| 81 | + loss = criterion(outputs, labels) |
| 82 | + loss.backward() |
| 83 | + optimizer.step() |
| 84 | + running_loss += loss.data[0] |
| 85 | + if i % 2000 == 1999: |
| 86 | + print('[%d, %5d] loss: %.3f' % (epoch + 1, i + 1, running_loss / 2000)) |
| 87 | + running_loss = 0.0 |
| 88 | +print('training done.') |
| 89 | + |
| 90 | +data_iter = iter(test_loader) |
| 91 | +images, labels = data_iter.next() |
| 92 | +imshow(torchvision.utils.make_grid(images)) |
| 93 | +print('GroundTruth: ', ' '.join('%5s' % classes[labels[j]] for j in range(4))) |
| 94 | + |
| 95 | +# predict |
| 96 | +outputs = network(Variable(images)) |
| 97 | +_, predicted = torch.max(outputs.data, 1) |
| 98 | +print('predicted: ', ' '.join('%5s' % classes[predicted[j]] for j in range(4))) |
| 99 | + |
| 100 | +correct = 0 |
| 101 | +total = 0 |
| 102 | +for data in test_loader: |
| 103 | + images, labels = data |
| 104 | + outputs = network(Variable(images)) |
| 105 | + _, predicted = torch.max(outputs.data, 1) |
| 106 | + total += labels.size(0) |
| 107 | + correct += (predicted == labels).sum() |
| 108 | +print('acc of 10000 test set: %f ' % (correct / total)) |
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