def set_grid(self, input_size): self.input_size = input_size self.grid_cell = self.create_grid(input_size) self.scale = np.array([[[input_size[1], input_size[0], input_size[1], input_size[0]]]]) self.scale_torch = torch.tensor(self.scale.copy(), device=self.device).float()

时间: 2024-04-18 22:26:35 浏览: 23
这段代码是一个方法，用于设置网格相关的参数。首先，将输入尺寸`input_size`保存到实例变量`self.input_size`中。然后调用`create_grid`方法生成网格矩阵，并将其保存到实例变量`self.grid_cell`中。接下来，创建一个形状为`[1, 1, 4]`的NumPy数组`scale`，其中包含了输入尺寸的四个坐标值`[input_size[1], input_size[0], input_size[1], input_size[0]]`。将该数组复制给变量`self.scale`。 最后，将`scale`数组复制一份，并将其转换为浮点型张量`scale_torch`，并将其移动到指定的设备上，并保存到实例变量`self.scale_torch`中。这个张量的形状为`[1, 1, 4]`，表示了输入尺寸的四个坐标值。
相关问题

请在这个DeepCFD的网络添加attention机制，并给出示例代码：import paddle import paddle.nn as nn class Attention(nn.Layer): def __init__(self, input_size, hidden_size): super(Attention, self).__init__() self.input_size = input_size self.hidden_size = hidden_size self.attn = nn.Linear(self.input_size + self.hidden_size, 1) self.softmax = nn.Softmax(axis=1) def forward(self, input, hidden): max_len = input.shape[0] attn_energies = paddle.zeros([max_len, 1]) for i in range(max_len): attn_energies[i] = self.score(input[i], hidden) attn_weights = self.softmax(attn_energies) context = paddle.sum(attn_weights * input, axis=0) return context.unsqueeze(0) def score(self, input, hidden): energy = self.attn(paddle.concat([input, hidden], axis=1)) return energy class DeepCFD(nn.Layer): def __init__(self, input_size, hidden_size, output_size): super(DeepCFD, self).__init__() self.input_size = input_size self.hidden_size = hidden_size self.output_size = output_size self.lstm = nn.LSTM(input_size, hidden_size, num_layers=2, batch_first=True) self.attention = Attention(input_size, hidden_size) self.fc = nn.Linear(hidden_size, output_size) def forward(self, input): output, (hidden, cell) = self.lstm(input) context = self.attention(output, hidden[-1]) output = self.fc(context) return output

好的，下面是添加了Attention机制的DeepCFD网络的示例代码： import paddle import paddle.nn as nn class Attention(nn.Layer): def __init__(self, input_size, hidden_size): super(Attention, self).__init__() self.input_size = input_size self.hidden_size = hidden_size self.attn = nn.Linear(self.input_size + self.hidden_size, 1) self.softmax = nn.Softmax(axis=1) def forward(self, input, hidden): max_len = input.shape[1] attn_energies = paddle.zeros([input.shape[0], max_len, 1]) for i in range(max_len): attn_energies[:, i] = self.score(input[:, i, :], hidden) attn_weights = self.softmax(attn_energies) context = paddle.sum(attn_weights * input, axis=1) return context def score(self, input, hidden): energy = self.attn(paddle.concat([input, hidden], axis=1)) return energy class DeepCFD(nn.Layer): def __init__(self, input_size, hidden_size, output_size): super(DeepCFD, self).__init__() self.input_size = input_size self.hidden_size = hidden_size self.output_size = output_size self.lstm = nn.LSTM(input_size, hidden_size, num_layers=2, batch_first=True) self.attention = Attention(input_size, hidden_size) self.fc = nn.Linear(hidden_size, output_size) def forward(self, input): output, (hidden, cell) = self.lstm(input) context = self.attention(output, hidden[-1]) output = self.fc(context) return output 在这个示例代码中，我们将Attention机制应用到了LSTM的输出上。在Attention中，我们计算了每个时间步的注意力能量，然后使用softmax函数计算注意力权重。然后，我们将这些权重与LSTM输出相乘并求和，得到上下文向量作为Attention机制的输出。 在DeepCFD中，我们使用了两层LSTM，然后将LSTM输出和最后一个时刻的隐藏状态作为Attention机制的输入。最后，我们将Attention机制的输出传递到一个全连接层中，得到最终的输出。

这段代码哪里错了 class my_BiGRU(torch.nn.Module): def __init__(self, input_size, hidden_size, num_layers, output_size, gru_dropout): super(my_BiGRU, self).__init__() self.input_size = input_size self.hidden_size = hidden_size self.num_layers = num_layers self.output_size = output_size self.gru_dropout = gru_dropout self.gru = torch.nn.GRU(input_size, hidden_size, num_layers=num_layers, batch_first=True, bidirectional=True) self.fc = torch.nn.Linear(hidden_size * 2, output_size) def _setup_BiGRU_layers(self): self.BiGRU_layers = my_BiGRU(input_size=self.args.capsule_out_dim, output_size=self.args.apsule_out_features, hidden_size=self.args.BiGRU_hiddensize, num_layers=self.args.BiGRU_layers, gru_dropout=self.args.BiGRU_dropout, )

这段代码存在两个问题： 1.函数 `_setup_BiGRU_layers` 中的代码应该是在类的构造函数 `__init__` 中进行初始化，而不是在另外一个函数中进行初始化。 2.在调用 `my_BiGRU` 类时，参数名称有误，应该将 `apsule_out_features` 改为 `capsule_out_features`。 改正后的代码如下所示： ``` class my_BiGRU(torch.nn.Module): def __init__(self, input_size, hidden_size, num_layers, output_size, gru_dropout, capsule_out_features): super(my_BiGRU, self).__init__() self.input_size = input_size self.hidden_size = hidden_size self.num_layers = num_layers self.output_size = output_size self.gru_dropout = gru_dropout self.gru = torch.nn.GRU(input_size, hidden_size, num_layers=num_layers, batch_first=True, bidirectional=True) self.fc = torch.nn.Linear(hidden_size * 2, output_size) self.BiGRU_layers = my_BiGRU(input_size=self.input_size, output_size=capsule_out_features, hidden_size=self.hidden_size, num_layers=self.num_layers, gru_dropout=self.gru_dropout, ) ``` 注意：这里假设 `capsule_out_dim` 和 `args` 都已经在代码中被定义好了。

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class LSTM(nn.Module): def __init__(self, input_size, hidden_size, num_layers, output_size, batch_size): super().__init__() self.input_size = input_size self.hidden_size = hidden_size self.num_layers = num_layers self.output_size = output_size self.num_directions = 1 # 单向LSTM self.batch_size = batch_size self.lstm = nn.LSTM(self.input_size, self.hidden_size, self.num_layers, batch_first=True) self.linear = nn.Linear(self.hidden_size, self.output_size) def forward(self, input_seq): batch_size, seq_len = input_seq[0], input_seq[1] h_0 = torch.randn(self.num_directions * self.num_layers, self.batch_size, self.hidden_size).to(device) c_0 = torch.randn(self.num_directions * self.num_layers, self.batch_size, self.hidden_size).to(device) # output(batch_size, seq_len, num_directions * hidden_size) output, _ = self.lstm(input_seq, (h_0, c_0)) pred = self.linear(output) pred = pred[:, -1, :] return pred这些代码分别是什么意思

- self.input_size = input_size、self.hidden_size = hidden_size、self.num_layers = num_layers、self.output_size = output_size、self.batch_size = batch_size 分别初始化模型的输入特征维度、隐藏...

解释class LSTM(nn.Module): def __init__(self, input_size, hidden_size, num_layers, batch_size, device="cpu"): super().__init__() self.device = device self.input_size = input_size self.hidden_size = hidden_size self.num_layers = num_layers self.batch_size = batch_size self.lstm = nn.LSTM(self.input_size, self.hidden_size, self.num_layers, batch_first=True, bidirectional=False)

然后，通过 nn.LSTM 类创建了一个名为 lstm 的 LSTM 模型，该模型的输入特征维度为 input_size，隐藏层维度为 hidden_size，层数为 num_layers，并且设置了 batch_first=True 表示输入数据的第一维为...

class NeuralNetwork: def __init__(self, layers_strcuture, print_cost = False): self.layers_strcuture = layers_strcuture self.layers_num = len(layers_strcuture) self.param_layers_num = self.layers_num - 1 self.learning_rate = 0.0618 self.num_iterations = 2000 self.x = None self.y = None self.w = dict() self.b = dict() self.costs = [] self.print_cost = print_cost self.init_w_and_b() def set_learning_rate(self,learning_rate): self.learning_rate=learning_rate def set_num_iterations(self, num_iterations): self.num_iterations = num_iterations def set_xy(self, input, expected_output): self.x = input self.y = expected_output

这段代码定义了一个名为Neural...该类还包含了一些其他方法，包括set_learning_rate()、set_num_iterations()和set_xy()等，用于设置神经网络的学习率、迭代次数和输入数据等。这些方法可以在实例化该类后进行调用。

def setup_layers(self): self.lstm = torch.nn.LSTM( input_size = self.lstm_inputsize, hidden_size = self.lstm_hiddensize, num_layers = self.lstm_layers, batch_first=True, dropout=(0 if self.lstm_layers == 1 else self.lstm_dropout), bidirectional=False )

input_size=self.lstm_inputsize, hidden_size=self.lstm_hiddensize, num_layers=self.lstm_layers, batch_first=True, dropout=(0 if self.lstm_layers == 1 else self.lstm_dropout), bidirectional=True )...

import torch import torch.nn as nn import torch.optim as optim import numpy as np 定义基本循环神经网络模型 class RNNModel(nn.Module): def init(self, rnn_type, input_size, hidden_size, output_size, num_layers=1): super(RNNModel, self).init() self.rnn_type = rnn_type self.input_size = input_size self.hidden_size = hidden_size self.output_size = output_size self.num_layers = num_layers self.encoder = nn.Embedding(input_size, hidden_size) if rnn_type == 'RNN': self.rnn = nn.RNN(hidden_size, hidden_size, num_layers) elif rnn_type == 'GRU': self.rnn = nn.GRU(hidden_size, hidden_size, num_layers) self.decoder = nn.Linear(hidden_size, output_size) def forward(self, input, hidden): input = self.encoder(input) output, hidden = self.rnn(input, hidden) output = output.view(-1, self.hidden_size) output = self.decoder(output) return output, hidden def init_hidden(self, batch_size): if self.rnn_type == 'RNN': return torch.zeros(self.num_layers, batch_size, self.hidden_size) elif self.rnn_type == 'GRU': return torch.zeros(self.num_layers, batch_size, self.hidden_size) 定义数据集 with open('汉语音节表.txt', encoding='utf-8') as f: chars = f.readline() chars = list(chars) idx_to_char = list(set(chars)) char_to_idx = dict([(char, i) for i, char in enumerate(idx_to_char)]) corpus_indices = [char_to_idx[char] for char in chars] 定义超参数 input_size = len(idx_to_char) hidden_size = 256 output_size = len(idx_to_char) num_layers = 1 batch_size = 32 num_steps = 5 learning_rate = 0.01 num_epochs = 100 定义模型、损失函数和优化器 model = RNNModel('RNN', input_size, hidden_size, output_size, num_layers) criterion = nn.CrossEntropyLoss() optimizer = optim.Adam(model.parameters(), lr=learning_rate) 训练模型 for epoch in range(num_epochs): model.train() hidden = model.init_hidden(batch_size) loss = 0 for X, Y in data_iter_consecutive(corpus_indices, batch_size, num_steps): optimizer.zero_grad() hidden = hidden.detach() output, hidden = model(X, hidden) loss = criterion(output, Y.view(-1)) loss.backward() torch.nn.utils.clip_grad_norm_(model.parameters(), max_norm=1.0) optimizer.step() if epoch % 10 == 0: print(f"Epoch {epoch}, Loss: {loss.item()}")请正确缩进代码

def __init__(self, rnn_type, input_size, hidden_size, output_size, num_layers=1): super(RNNModel, self).__init__() self.rnn_type = rnn_type self.input_size = input_size self.hidden_size = ...

class Net(nn.Module): def __init__(self,input_size,hidden_size,num_layers,output_size,batch_size,seq_length) -> None: super(Net,self).__init__() self.input_size=input_size self.hidden_size=hidden_size self.num_layers=num_layers self.output_size=output_size self.batch_size=batch_size self.seq_length=seq_length self.num_directions=1 # 单向LSTM self.lstm=nn.LSTM(input_size=input_size,hidden_size=hidden_size,num_layers=num_layers,batch_first=True) # LSTM层 self.fc=nn.Linear(hidden_size,output_size) # 全连接层 def forward(self,x): # e.g. x(10,3,100) 三个句子，十个单词，一百维的向量,nn.LSTM(input_size=100,hidden_size=20,num_layers=4) # out.shape=(10,3,20) h/c.shape=(4,b,20) batch_size, seq_len = x.size()[0], x.size()[1] # x.shape=(604,3,3) h_0 = torch.randn(self.num_directions * self.num_layers, x.size(0), self.hidden_size) c_0 = torch.randn(self.num_directions * self.num_layers, x.size(0), self.hidden_size) # output(batch_size, seq_len, num_directions * hidden_size) output, _ = self.lstm(x, (h_0, c_0)) # output(5, 30, 64) pred = self.fc(output) # (5, 30, 1) pred = pred[:, -1, :] # (5, 1) return pred改成python代码

def __init__(self, input_size, hidden_size, num_layers, output_size, batch_size, seq_length): super(Net, self).__init__() self.input_size = input_size self.hidden_size = hidden_size self.num_...

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class LSTM(nn.Module): def __init__(self, input_size, hidden_size, num_layers, batch_size, device="cpu"): super().__init__() self.device = device self.input_size = input_size self.hidden_size = hidden_size self.num_layers = num_layers self.batch_size = batch_size self.lstm = nn.LSTM(self.input_size, self.hidden_size, self.num_layers, batch_first=True, bidirectional=False) def forward(self, input_seq): batch_size, seq_len = input_seq.shape[0], input_seq.shape[1] h_0 = torch.randn(self.num_layers, batch_size, self.hidden_size).to(self.device) c_0 = torch.randn(self.num_layers, batch_size, self.hidden_size).to(self.device) output, (h, c) = self.lstm(input_seq, (h_0, c_0)) return output, h

然后，通过 nn.LSTM 类创建了一个名为 lstm 的 LSTM 模型，该模型的输入特征维度为 input_size，隐藏层维度为 hidden_size，层数为 num_layers，并且设置了 batch_first=True 表示输入数据的第一维为...

class LogisticRegression(object): def __init__(self, input_size, output_size, eta, max_epoch, eps):

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class my_BiGRU(torch.nn.Module): def __init__(self, input_size, hidden_size, num_layers, output_size, gru_dropout): super(my_BiGRU, self).__init__() self.input_size = input_size self.hidden_size = hidden_size self.num_layers = num_layers self.output_size = output_size self.gru_dropout = gru_dropout self.gru = torch.nn.GRU(input_size, hidden_size, num_layers=num_layers, batch_first=True, bidirectional=True) self.fc = torch.nn.Linear(hidden_size * 2, output_size) def forward(self, x): h0 = torch.zeros(self.num_layers * 2, x.size(0), self.hidden_size).to(x.device) out, _ = self.gru(x, h0) out = self.fc(out[:, -1, :]) return out

该模型的输入大小为input_size，输出大小为output_size。它有num_layers层双向GRU，每层的隐藏状态大小为hidden_size。在GRU层之后，它使用全连接层将GRU的输出转换为所需的输出大小。该模型还使用了dropout来减少过...

class my_LSTM(torch.nn.Module): def __init__(self, lstm_inputsize, lstm_hiddensize, lstm_layers, lstm_dropout): super(my_LSTM, self).__init__() self.lstm_inputsize = lstm_inputsize self.lstm_hiddensize = lstm_hiddensize self.lstm_layers = lstm_layers self.lstm_dropout = lstm_dropout self.setup_layers() def setup_layers(self): self.lstm = torch.nn.LSTM( input_size = self.lstm_inputsize, hidden_size = self.lstm_hiddensize, num_layers = self.lstm_layers, batch_first=True, dropout=(0 if self.lstm_layers == 1 else self.lstm_dropout), bidirectional=False ) def forward(self, input): out, (h_n, c_n) = self.lstm(input) return out[:, -1, :]

该模型的输入大小为lstm_inputsize，隐藏状态大小为lstm_hiddensize，LSTM的层数为lstm_layers。该模型还使用了dropout来减少过拟合。在setup_layers函数中，该模型设置了一个LSTM层。在forward函数中，它将输入...

def __init__(self, input_size, hidden_size, output_size): super(Net, self).__init__() self.rnn = nn.LSTM(input_size, hidden_size, num_layers=2, batch_first=True) self.fc = nn.Linear(hidden_size, output_size) def forward(self, x): out, _ = self.rnn(x) out = self.fc(out[:, -1, :]) return out

这个模型的输入是一批数据，每个数据的维度为 (batch_size, sequence_length, input_size)，其中 batch_size 表示一批数据的大小，sequence_length 表示序列的长度，input_size 表示每个时间步的输入特征维度。...

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