optim_v = torch.optim.Adam(vnet.parameters(), lr=1e-3)
时间: 2024-06-15 22:06:52 浏览: 128
optim_v = torch.optim.Adam(vnet.parameters(), lr=1e-3) 是一个用于优化神经网络模型参数的优化器对象的创建过程。具体来说,它使用Adam算法来更新模型参数,并且学习率(lr)设置为1e-3。
Adam是一种常用的优化算法,它结合了动量法和自适应学习率的特性,能够在训练过程中自适应地调整学习率。通过计算梯度的一阶矩估计和二阶矩估计,Adam算法能够更好地适应不同参数的梯度情况,从而提高模型的收敛速度和性能。
在这里,vnet.parameters()表示需要优化的模型参数,lr=1e-3表示学习率设置为0.001。通过调用Adam类并传入这些参数,我们可以创建一个优化器对象optim_v,用于更新模型参数。
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optimizer = torch.optim.Adam(learnable_params) opt = optim.Adam(model.parameters(), lr=args.lr, weight_decay=1e-4) scheduler = torch.optim.lr_scheduler.MultiStepLR(opt, milestones=[50, 100, 150], gamma=0.1)
这段代码是使用PyTorch框架进行模型训练的示例代码。其中:
1. `optimizer = torch.optim.Adam(learnable_params)`用于定义优化器,其中`learnable_params`表示需要更新的参数。
2. `opt = optim.Adam(model.parameters(), lr=args.lr, weight_decay=1e-4)`用于定义优化器,其中`model.parameters()`表示需要更新的参数,`args.lr`表示学习率,`weight_decay`表示权重衰减。
3. `scheduler = torch.optim.lr_scheduler.MultiStepLR(opt, milestones=[50, 100, 150], gamma=0.1)`用于定义学习率调度器,其中`opt`表示要调度学习率的优化器,`milestones`表示调整学习率的epoch数,`gamma`表示学习率调整的倍数。
综合来看,这段代码定义了一个Adam优化器,并使用了学习率衰减策略。在训练过程中,每经过50、100、150个epoch就会将学习率乘以0.1,以便在训练后期更加稳定地收敛。
修改一下这段代码在pycharm中的实现,import pandas as pd import numpy as np from sklearn.model_selection import train_test_split import torch import torch.nn as nn import torch.nn.functional as F import torch.optim as optim #from torchvision import datasets,transforms import torch.utils.data as data #from torch .nn:utils import weight_norm import matplotlib.pyplot as plt from sklearn.metrics import precision_score from sklearn.metrics import recall_score from sklearn.metrics import f1_score from sklearn.metrics import cohen_kappa_score data_ = pd.read_csv(open(r"C:\Users\zhangjinyue\Desktop\rice.csv"),header=None) data_ = np.array(data_).astype('float64') train_data =data_[:,:520] train_Data =np.array(train_data).astype('float64') train_labels=data_[:,520] train_labels=np.array(train_data).astype('float64') train_data,train_data,train_labels,train_labels=train_test_split(train_data,train_labels,test_size=0.33333) train_data=torch.Tensor(train_data) train_data=torch.LongTensor(train_labels) train_data=train_data.reshape(-1,1,20,26) train_data=torch.Tensor(train_data) train_data=torch.LongTensor(train_labels) train_data=train_data.reshape(-1,1,20,26) start_epoch=1 num_epoch=1 BATCH_SIZE=70 Ir=0.001 classes=('0','1','2','3','4','5') device=torch.device("cuda"if torch.cuda.is_available()else"cpu") torch.backends.cudnn.benchmark=True best_acc=0.0 train_dataset=data.TensorDataset(train_data,train_labels) test_dataset=data.TensorDataset(train_data,train_labels) train_loader=torch.utills.data.DataLoader(dtaset=train_dataset,batch_size=BATCH_SIZE,shuffle=True) test_loader=torch.utills.data.DataLoader(dtaset=train_dataset,batch_size=BATCH_SIZE,shuffle=True)
修改后的代码如下所示:
```python
import pandas as pd
import numpy as np
from sklearn.model_selection import train_test_split
import torch
import torch.nn as nn
import torch.nn.functional as F
import torch.optim as optim
import torch.utils.data as data
import matplotlib.pyplot as plt
from sklearn.metrics import precision_score, recall_score, f1_score, cohen_kappa_score
data_ = pd.read_csv(r"C:\Users\zhangjinyue\Desktop\rice.csv", header=None)
data_ = np.array(data_).astype('float64')
train_data = data_[:, :520]
train_labels = data_[:, 520]
train_data, _, train_labels, _ = train_test_split(train_data, train_labels, test_size=0.33333)
train_data = torch.Tensor(train_data)
train_labels = torch.LongTensor(train_labels)
train_data = train_data.reshape(-1, 1, 20, 26)
start_epoch = 1
num_epoch = 1
BATCH_SIZE = 70
Ir = 0.001
classes = ('0', '1', '2', '3', '4', '5')
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
torch.backends.cudnn.benchmark = True
best_acc = 0.0
train_dataset = data.TensorDataset(train_data, train_labels)
test_dataset = data.TensorDataset(train_data, train_labels)
train_loader = torch.utils.data.DataLoader(dataset=train_dataset, batch_size=BATCH_SIZE, shuffle=True)
test_loader = torch.utils.data.DataLoader(dataset=train_dataset, batch_size=BATCH_SIZE, shuffle=True)
```
请注意,我做了以下修改:
1. 移除了不需要的导入语句。
2. 修复了变量名拼写错误。
3. 移除了重复的代码行。
4. 修正了 `torch.utils.data.DataLoader` 的拼写错误。
5. 修正了数据集分割时的变量名错误。
请根据你的实际需求进一步调整代码。