I am new to Deep Learning and PyTorch. I am using the resnet-50 model in the torchvision module on cifar10. The accuracy is very low on testing. Is there something wrong with my code?
import torchvision
import torch
import torch.nn as nn
from torch import optim
import os
import torchvision.transforms as transforms
from torch.utils.data import DataLoader
import numpy as np
from collections import OrderedDict
import matplotlib.pyplot as plt
transformations=transforms.Compose([transforms.ToTensor(),transforms.Normalize([0.485, 0.456, 0.406],[0.229, 0.224, 0.225])])
trainset=torchvision.datasets.CIFAR10(root='./CIFAR10',download=True,transform=transformations,train=True)
testset=torchvision.datasets.CIFAR10(root='./CIFAR10',download=True,transform=transformations,train=False)
trainloader=DataLoader(dataset=trainset,batch_size=4)
testloader=DataLoader(dataset=testset,batch_size=4)
inputs,labels=next(iter(trainloader))
labels=labels.float()
inputs.size()
print(labels.type())
resnet=torchvision.models.resnet50(pretrained=True)
if torch.cuda.is_available():
resnet=resnet.cuda()
inputs,labels=inputs.cuda(),torch.Tensor(labels).cuda()
outputs=resnet(inputs)
outputs.size()
for param in resnet.parameters():
param.requires_grad=False
numft=resnet.fc.in_features
print(numft)
resnet.fc=torch.nn.Sequential(nn.Linear(numft,1000),nn.ReLU(),nn.Linear(1000,10))
resnet.cuda()
resnet.train(True)
optimizer=torch.optim.SGD(resnet.parameters(),lr=0.001,momentum=0.9)
criterion=nn.CrossEntropyLoss()
for epoch in range(5):
resnet.train(True)
trainloss=0
correct=0
for x,y in trainloader:
x,y=x.cuda(),y.cuda()
optimizer.zero_grad()
yhat=resnet(x)
loss=criterion(yhat,y)
loss.backward()
optimizer.step()
trainloss+=loss.item()
print('Epoch: {} Loss: {}'.format(epoch,(trainloss/len(trainloader))))
accuracy=[]
running_corrects=0.0
for x_test,y_test in testloader:
x_test,y_test=x_test.cuda(),y_test.cuda()
yhat=resnet(x_test)
_,z=yhat.max(1)
running_corrects += torch.sum(y_test == z)
accuracy.append(running_corrects/len(testloader))
print(running_corrects/len(testloader))
accuracy=max(accuracy)
print(accuracy)
OUTPUT AFTER TRAINING/TESTING
Epoch: 0 Loss: 1.9808503997325897
Epoch: 1 Loss: 1.7917569598436356
Epoch: 2 Loss: 1.624434965057373
Epoch: 3 Loss: 1.4082191940283775
Epoch: 4 Loss: 1.1343850775527955
tensor(1.1404, device='cuda:0')
tensor(1.1404, device='cuda:0')