Day33 参加职训(机器学习与资料分析工程师培训班)，网站设计与网页工程技术

上午: AIoT资料分析应用系统框架设计与实作

今日运用Django架设Framework，只完成一部份，下次课程会继续完成，画面如下:

下午: Pytroch与深度学习初探
使用CNN建构网路，预测MNIST

######################### step1: load data (generate) ############
import torch
import torch.nn as nn
import torch.nn.functional as F 
import matplotlib.pyplot as plt
import numpy as np
from torchvision import datasets, transforms

#Assign cuda GPU located at location '0' to a variable
# device= torch.device('cuda:0')
print(torch.cuda.device_count())
print(torch.cuda.get_device_name(0))
device = torch.device("cuda:0" if torch.cuda.is_available() else "cpu")
print(device)


t1=transforms.Resize((28,28))
t2=transforms.ToTensor()
t3=transforms.Normalize((0.5,),(0.5,))
transform=transforms.Compose([t1,t2,t3])
train_data= datasets.MNIST(root='./data',train=True, download=True, transform=transform)
validate_data=datasets.MNIST(root='./data',train=False, download=True, transform=transform)
print(len(train_data),type(train_data))
print(len(validate_data),type(validate_data))

train_loader=torch.utils.data.DataLoader(train_data, batch_size=100,shuffle=True)
validation_loader=torch.utils.data.DataLoader(validate_data,batch_size=100,shuffle=False)

print(len(train_loader),type(train_loader))
print(len(validation_loader),type(validation_loader))

def im_convert(tensor):
  image = tensor.clone().detach().numpy()
  image = image.transpose(1, 2, 0)
  image = image * np.array((0.5, 0.5, 0.5)) + np.array((0.5, 0.5, 0.5))
  image = image.clip(0, 1)
  return image
  
dataiter = iter(train_loader)

images, labels = dataiter.next()
fig = plt.figure(figsize=(25, 4))

for idx in np.arange(20):
  ax = fig.add_subplot(2, 10, idx+1, xticks=[], yticks=[])
  plt.imshow(im_convert(images[idx]))
  ax.set_title([labels[idx].item()])

########################### step3: build model ############

class LeNet(nn.Module):
  def __init__(self):
    super().__init__()
    self.conv1 = nn.Conv2d(1, 20, 5, 1)
    self.conv2 = nn.Conv2d(20, 50, 5, 1)
    self.fc1 = nn.Linear(4*4*50, 500)
    self.dropout1 = nn.Dropout(0.5)
    self.fc2 = nn.Linear(500, 10)
  def forward(self, x):
    x = F.relu(self.conv1(x))
    x = F.max_pool2d(x, 2, 2)
    x = F.relu(self.conv2(x))
    x = F.max_pool2d(x, 2, 2)
    x = x.view(-1, 4*4*50)
    x = F.relu(self.fc1(x))
    x = self.dropout1(x)
    x = self.fc2(x)
    return x

model=LeNet().to(device)
print(model)
# class myDNN(nn.Module):
#  def __init__(self,numIn,numH1,numH2,numOut):
#   super(myDNN,self).__init__()
#   self.layer1=torch.nn.Linear(numIn,numH1)
#   self.layer2=torch.nn.Linear(numH1,numH2)
#   self.layer3=torch.nn.Linear(numH2,numOut)
#  def forward(self,x):
#   x=F.relu(self.layer1(x))
#   x=F.relu(self.layer2(x))
#   yProb=self.layer3(x)
#   return yProb

# model=myDNN(784,256,64,10)


#backward path
criterion= nn.CrossEntropyLoss()
optimizer=torch.optim.Adam(model.parameters(),lr=0.0001)#advance 2:lr=0.0001

############################ step4: traing model############
epochs = 15
running_loss_history = []
running_corrects_history = []
val_running_loss_history = []
val_running_corrects_history = []

for e in range(epochs):
  
  running_loss = 0.0
  running_corrects = 0.0
  val_running_loss = 0.0
  val_running_corrects = 0.0
  
  for inputs, labels in train_loader:
    inputs = inputs.to(device)
    labels= labels.to(device)
    outputs = model(inputs)
    loss = criterion(outputs, labels)
    
    optimizer.zero_grad()
    loss.backward()
    optimizer.step()
    
    _, preds = torch.max(outputs, 1)
    running_loss += loss.item()
    running_corrects += torch.sum(preds == labels.data)

  else:
    with torch.no_grad():
      for val_inputs, val_labels in validation_loader:
        val_inputs = val_inputs.to(device)
        val_labels = val_labels.to(device)
        val_outputs = model(val_inputs)
        val_loss = criterion(val_outputs, val_labels)
        
        _, val_preds = torch.max(val_outputs, 1)
        val_running_loss += val_loss.item()
        val_running_corrects += torch.sum(val_preds == val_labels.data)
      
    epoch_loss = running_loss/len(train_loader)
    epoch_acc = running_corrects.float()/ len(train_loader)
    running_loss_history.append(epoch_loss)
    running_corrects_history.append(epoch_acc)
    
    val_epoch_loss = val_running_loss/len(validation_loader)
    val_epoch_acc = val_running_corrects.float()/ len(validation_loader)
    val_running_loss_history.append(val_epoch_loss)
    val_running_corrects_history.append(val_epoch_acc)
    print('epoch :', (e+1))
    print('training loss: {:.4f}, acc {:.4f} '.format(epoch_loss, epoch_acc.item()))
    print('validation loss: {:.4f}, validation acc {:.4f} '.format(val_epoch_loss, val_epoch_acc.item()))