126 lines
3.5 KiB
Python
126 lines
3.5 KiB
Python
import matplotlib.pyplot as plt
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import numpy as np
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import torch
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import torch.nn as nn
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import torch.nn.functional as F
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from torch.utils.data import DataLoader
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from torchvision import datasets, transforms
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# Super parameters
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batch_size = 64
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learning_rate = 0.01
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momentum = 0.5
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EPOCH = 10
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# Prepare dataset
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transform = transforms.Compose(
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[transforms.ToTensor(), transforms.Normalize((0.1307,), (0.3081,))]
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)
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train_dataset = datasets.MNIST(
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root="./data/mnist", train=True, download=True, transform=transform
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)
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test_dataset = datasets.MNIST(
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root="./data/mnist", train=False, download=True, transform=transform
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)
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train_loader = DataLoader(train_dataset, batch_size=batch_size, shuffle=True)
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test_loader = DataLoader(test_dataset, batch_size=batch_size, shuffle=False)
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class Net(torch.nn.Module):
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def __init__(self):
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super(Net, self).__init__()
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self.fc1 = torch.nn.Linear(28 * 28, 512)
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self.fc2 = torch.nn.Linear(512, 128)
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self.fc3 = torch.nn.Linear(128, 10)
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def forward(self, x):
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x = x.view(-1, 28 * 28)
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x = F.relu(self.fc1(x))
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x = F.relu(self.fc2(x))
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x = self.fc3(x)
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return x
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# Create two models for comparison
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model_sgd = Net()
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model_adam = Net()
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# Create different optimizers
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optimizer_sgd = torch.optim.SGD(
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model_sgd.parameters(), lr=learning_rate, momentum=momentum
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)
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optimizer_adam = torch.optim.Adam(model_adam.parameters(), lr=learning_rate)
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criterion = torch.nn.CrossEntropyLoss()
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def train(epoch, model, optimizer, name=""):
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model.train()
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running_loss = 0.0
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running_total = 0
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running_correct = 0
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for batch_idx, (inputs, target) in enumerate(train_loader):
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optimizer.zero_grad()
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outputs = model(inputs)
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loss = criterion(outputs, target)
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loss.backward()
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optimizer.step()
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running_loss += loss.item()
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_, predicted = torch.max(outputs.data, dim=1)
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running_total += target.shape[0]
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running_correct += (predicted == target).sum().item()
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avg_loss = running_loss / len(train_loader)
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avg_acc = 100 * running_correct / running_total
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print(
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f"[{epoch + 1} / {EPOCH}]: {name} Training Loss: {avg_loss:.3f}, Training Accuracy: {avg_acc:.2f} %"
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)
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def test(epoch, model, name=""):
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model.eval()
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correct = 0
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total = 0
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with torch.no_grad():
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for data in test_loader:
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images, labels = data
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outputs = model(images)
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_, predicted = torch.max(outputs.data, dim=1)
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total += labels.size(0)
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correct += (predicted == labels).sum().item()
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acc = 100 * correct / total
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print(
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f"[{epoch + 1} / {EPOCH}]: {name} Accuracy on test set after epoch {epoch + 1}: {acc:.1f} %"
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)
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return acc
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if __name__ == "__main__":
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acc_list_sgd = []
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acc_list_adam = []
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for epoch in range(EPOCH):
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train(epoch, model_sgd, optimizer_sgd, "SGD")
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train(epoch, model_adam, optimizer_adam, "Adam")
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acc_sgd = test(epoch, model_sgd, "SGD")
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acc_adam = test(epoch, model_adam, "Adam")
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acc_list_sgd.append(acc_sgd)
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acc_list_adam.append(acc_adam)
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plt.figure(figsize=(10, 6))
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plt.plot(range(1, EPOCH + 1), acc_list_sgd, label="SGD", marker="o")
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plt.plot(range(1, EPOCH + 1), acc_list_adam, label="Adam", marker="s")
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plt.xlabel("Epoch")
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plt.ylabel("Accuracy On TestSet (%)")
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plt.title("Comparison of Optimizers: SGD vs Adam")
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plt.legend()
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plt.grid(True)
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plt.show()
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