add train neural network script

NeuralNetwork/train_nn.py

@@ -0,0 +1,49 @@
+import torch
+import torch.nn as nn
+import torchvision.transforms as transforms
+import torch.optim as optim
+from torch.utils.data import DataLoader
+from torchvision.datasets import ImageFolder
+from NeuralNetwork import NeuralNetwork
+
+# import matplotlib.pyplot as plt
+# import numpy as np
+# import cv2
+
+def trainNeuralNetwork():
+    neural_net = NeuralNetwork()
+    train_set = ImageFolder(root='./resources/trash_dataset/train', transform=transforms.Compose([transforms.ToTensor(),transforms.Normalize((0.5, 0.5, 0.5), (0.5, 0.5, 0.5))]))
+    trainloader = DataLoader(
+        train_set, batch_size=2, shuffle=True, num_workers=2)
+
+    # potrzebne do wyświetlania loss w każdej iteracji
+    criterion = nn.CrossEntropyLoss()
+    optimizer = optim.SGD(neural_net.parameters(), lr=0.001, momentum=0.9)
+
+    epoch_num = 4 # najlepiej 10, dla lepszej wiarygodności
+    for epoch in range(epoch_num):
+        measure_loss = 0.0
+        for i, data in enumerate(trainloader, 0):
+            inputs, labels = data
+            # czyszczenie gradientu f-cji
+            optimizer.zero_grad()
+            outputs = neural_net(inputs)
+            loss = criterion(outputs, labels)
+            loss.backward()
+            optimizer.step()
+            measure_loss += loss.item()
+            if i:
+                print('[%d, %5d] loss: %.3f' %
+                      (epoch + 1, i + 1, measure_loss))
+                measure_loss = 0.0
+
+    print('Finished.')
+    PATH = './trained_nn.pth'
+    torch.save(neural_net.state_dict(), PATH)
+
+def main():
+    trainNeuralNetwork()
+
+if __name__ == '__main__':
+    main()
+