原因在於沒有使用torch.no_grad()函數。在查看驗證集和測試集表現時,應使用類似這樣的代碼
def evaluate(data_loader):
with torch.no_grad():
mean_acc, mean_iou = 0, 0
for i, (img, gnd) in enumerate(data_loader):
if torch.cuda.is_available():
img = img.cuda(device=device)
gnd = gnd.cuda(device=device)
out = model(img)
.......
return mean_acc / len(data_loader), mean_iou / len(data_loader)