def Focal_Loss(inputs, target, cls_weights, num_classes=21, alpha=0.5, gamma=2): n, c, h, w = inputs.size() nt, ht, wt = target.size() if h != ht and w != wt: inputs = F.interpolate(inputs, size=(ht, wt), mode="bilinear", align_corners=True) temp_inputs = inputs.transpose(1, 2).transpose(2, 3).contiguous().view(-1, c) temp_target = target.view(-1) logpt = -nn.CrossEntropyLoss(weight=cls_weights, ignore_index=num_classes, reduction='none')(temp_inputs, temp_target) pt = torch.exp(logpt) if alpha is not None: logpt *= alpha loss = -((1 - pt) ** gamma) * logpt loss = loss.mean() return loss 是什么意思

Pytorch-Triplet_loss:用Pytorch实现三重损失

**Pytorch-Triplet_loss: 用Pytorch实现三重损失** 在深度学习领域，损失函数是模型训练的核心部分，它衡量模型预测结果与实际标签之间的差距。其中，三重损失（Triplet Loss）是一种在计算机视觉任务，尤其是人脸...

device-to-device-matlap-(3).rar_d2d_d2d lte_device to device

This research involved close collaboration with and significant technical inputs the Head of NSN North America Radio Systems, Amitava Ghosh, and Principal Engineer Mazin Al-Shalash WNCG Industrial ...

Focal loss代码如下：class FocalLoss(nn.Module): def init(self, alpha=1, gamma=2, weight=None): super(FocalLoss, self).init() self.alpha = alpha self.gamma = gamma def forward(self, x: torch.Tensor, target: torch.Tensor) -> torch.Tensor: log_probs = F.log_softmax(x, dim=-1) probs = torch.exp(log_probs) focal_loss = -self.alpha * (torch.pow((1 - probs), self.gamma)) * log_probs loss = torch.sum(target * focal_loss, dim=-1) return loss.mean() LDAM loss 代码如下：class LDAMLoss(nn.Module): def init(self, cls_num_list, max_m=0.5, weight=None, s=30): super(LDAMLoss, self).init() m_list = 1.0 / np.sqrt(np.sqrt(cls_num_list)) m_list = m_list * (max_m / np.max(m_list)) m_list = torch.cuda.FloatTensor(m_list) self.m_list = m_list assert s > 0 self.s = s self.weight = weight def forward(self, x, target): index = torch.zeros_like(x, dtype=torch.uint8) index.scatter_(1, target.data.view(-1, 1), 1) index_float = index.type(torch.cuda.FloatTensor) batch_m = torch.matmul(self.m_list[None, :], index_float.transpose(0,1)) batch_m = batch_m.view((-1, 1)) x_m = x - batch_m output = torch.where(index, x_m, x) return F.cross_entropy(self.s*output, target, weight=self.weight) LMF loss 是Focal loss 和LDAM loss两个损失函数的加权求和，请用pytorch代码实现LMF损失函数并在模型训练中使用

def __init__(self, cls_num_list, max_m=0.5, weight=None, s=30, alpha=0.25, gamma=2, beta=0.5): super(LMF, self).__init__() self.focal_loss = FocalLoss(alpha=alpha, gamma=gamma, weight=weight) self...

Focal 损失函数代码如下：def focal_loss(input_values, gamma): """Computes the focal loss""" p = torch.exp(-input_values) loss = (1 - p) ** gamma * input_values return loss.mean() class FocalLoss(nn.Module): def init(self, weight=None, gamma=0.): super(FocalLoss, self).init() assert gamma >= 0 self.gamma = gamma self.weight = weight def forward(self, input, target): return focal_loss(F.cross_entropy(input, target, reduction='none', weight=self.weight), self.gamma) LDAM损失函数代码如下：class LDAMLoss(nn.Module): def init(self, cls_num_list, max_m=0.5, weight=None, s=30): super(LDAMLoss, self).init() m_list = 1.0 / np.sqrt(np.sqrt(cls_num_list)) m_list = m_list * (max_m / np.max(m_list)) m_list = torch.cuda.FloatTensor(m_list) self.m_list = m_list assert s > 0 self.s = s self.weight = weight def forward(self, x, target): index = torch.zeros_like(x, dtype=torch.uint8) index.scatter_(1, target.data.view(-1, 1), 1) index_float = index.type(torch.cuda.FloatTensor) batch_m = torch.matmul(self.m_list[None, :], index_float.transpose(0,1)) batch_m = batch_m.view((-1, 1)) x_m = x - batch_m output = torch.where(index, x_m, x) return F.cross_entropy(self.s*output, target, weight=self.weight) Large Margin aware Focal (LMF) 损失函数是 Focal 损失函数和 LDAM损失函数加权的线性组合，帮我用pytorch代码实现LMF损失函数并在模型中使用

criterion = LMF_Loss(cls_num_list=[class0_num, class1_num, class2_num], max_m=0.5, weight=class_weights, s=30, gamma=2.0, alpha=0.25) optimizer = torch.optim.Adam(model.parameters(), lr=0.01) for ...

def mcp_loss(y_true, y_pred): """ 计算单调性约束损失函数在所有样本和时刻上的平均值 """ batch_size=64 num_timesteps=6 delta_p = tf.random.uniform(shape=(batch_size, num_timesteps, 15), minval=0, maxval=1) p = inputs[:, :, -15:] # 取原始输入数据的最后15列作为 p p_new = p + delta_p newinputs = tf.concat([inputs[:, :, 0:1], p_new], axis=-1) y_pred_ = model(newinputs) y_true_ = model(inputs) return tf.keras.losses.mean_squared_error(y_true_, y_pred_) def combined_loss(y_true, y_pred): """ 组合MSE损失函数和单调性约束损失函数的新损失函数 """ alpha = 0.5 # 可以根据需要进行调整 mse_loss = mean_squared_error(y_true, y_pred) mcp_loss_val = mcp_loss(y_true, y_pred) return alpha * mse_loss + (1 - alpha) * mcp_loss_val将以上代码修改为kera能识别的代码

alpha = 0.5 # 可以根据需要进行调整 mse_loss = mean_squared_error(y_true, y_pred) mcp_loss_val = mcp_loss(y_true, y_pred) return alpha * mse_loss + (1 - alpha) * mcp_loss_val

sample = next(iter(train_ds)) inputs_shape = sample[0].shape[1:] inputs = keras.Input(shape=inputs_shape) # 输入层 def mcp_loss(y_true, y_pred, delta_p, model): p = y_pred[:, :, 0] # 取出所有样本和时间步的输入 p f = y_true[:, :, 0] # 取出所有样本和时间步的标签 f p_new = tf.expand_dims(p + delta_p, axis=-1) f_new = model(p_new)[:, :, 0] delta_f = f - f_new relu = tf.nn.relu(delta_f) return tf.reduce_mean(tf.square(relu)) def combined_loss(y_true, y_pred, delta_p, model, alpha=0.5): mse_loss = tf.keras.losses.mean_squared_error(y_true, y_pred) mcp_loss1 = mcp_loss(y_true, y_pred, delta_p, model) return alpha * mse_loss + (1-alpha) * mcp_loss1 model = model_attention_applied_before_lstm() combined_loss1=combined_loss() model.compile(optimizer=keras.optimizers.Adam(0.001), loss=combined_loss1) epochs = 80 # 网络训练 history = model.fit(train_ds, epochs=epochs, validation_data=val_ds)结合前面的训练数据集将这段代码的combined_loss1补充完整

根据代码中的定义，combined_loss函数接收5个参数：y_true表示真实标签，y_pred表示模型的预测结果，delta_p是一个标量，model是一个Keras模型，alpha是一个可选的参数，默认值为0.5。 combined_loss...

def mcp_loss(f_new): """ 计算单调性约束损失函数在所有样本和时刻上的平均值 """ batch_size = 64 num_timesteps = 6 num_features = 15 delta_p = tf.random.uniform(shape=(batch_size, num_timesteps, num_features), minval=0, maxval=1) p = inputs[:, :, -15:] p_new = p + delta_p newinputs = np.concatenate([train_ds[:, :, 0], p_new], axis=-1) f = ssmodel.predict(train_ds) f_new = ssmodel.predict(newinputs) # 预测 f_new delta_f = f - f_new relu = tf.nn.relu(delta_f) return tf.reduce_mean(tf.square(relu)) def combined_loss(y_true, y_pred): """ 组合MSE损失函数和单调性约束损失函数的新损失函数 """ def loss(y_true,y_pred): return alpha* mean_squared_error(y_true, y_pred) + (1-alpha) * mcp_loss() return loss将这段代码修改为keras的自定义损失函数的正确形式

alpha = 0.5 # 可以根据需要进行调整 mse_loss = mean_squared_error(y_true, y_pred) mcp_loss_val = mcp_loss(y_true, y_pred) return alpha * mse_loss + (1 - alpha) * mcp_loss_val 在上述代码中，...

LDAM损失函数pytorch代码如下：class LDAMLoss(nn.Module): def init(self, cls_num_list, max_m=0.5, weight=None, s=30): super(LDAMLoss, self).init() m_list = 1.0 / np.sqrt(np.sqrt(cls_num_list)) m_list = m_list * (max_m / np.max(m_list)) m_list = torch.cuda.FloatTensor(m_list) self.m_list = m_list assert s > 0 self.s = s if weight is not None: weight = torch.FloatTensor(weight).cuda() self.weight = weight self.cls_num_list = cls_num_list def forward(self, x, target): index = torch.zeros_like(x, dtype=torch.uint8) index_float = index.type(torch.cuda.FloatTensor) batch_m = torch.matmul(self.m_list[None, :], index_float.transpose(1,0)) # 0,1 batch_m = batch_m.view((16, 1)) # size=(batch_size, 1) (-1,1) x_m = x - batch_m output = torch.where(index, x_m, x) if self.weight is not None: output = output * self.weight[None, :] target = torch.flatten(target) # 将 target 转换成 1D Tensor logit = output * self.s return F.cross_entropy(logit, target, weight=self.weight) 模型部分参数如下：# 设置全局参数 model_lr = 1e-5 BATCH_SIZE = 16 EPOCHS = 50 DEVICE = torch.device('cuda:0' if torch.cuda.is_available() else 'cpu') use_amp = True use_dp = True classes = 7 resume = None CLIP_GRAD = 5.0 Best_ACC = 0 #记录最高得分 use_ema=True model_ema_decay=0.9998 start_epoch=1 seed=1 seed_everything(seed) # 数据增强 mixup mixup_fn = Mixup( mixup_alpha=0.8, cutmix_alpha=1.0, cutmix_minmax=None, prob=0.1, switch_prob=0.5, mode='batch', label_smoothing=0.1, num_classes=classes) # 读取数据集 dataset_train = datasets.ImageFolder('/home/adminis/hpy/ConvNextV2_Demo/RAF-DB/RAF/train', transform=transform) dataset_test = datasets.ImageFolder("/home/adminis/hpy/ConvNextV2_Demo/RAF-DB/RAF/valid", transform=transform_test) 帮我用pytorch实现模型在模型训练中使用LDAM损失函数

def __init__(self, cls_num_list, max_m=0.5, weight=None, s=30): super(LDAMLoss, self).__init__() m_list = 1.0 / np.sqrt(np.sqrt(cls_num_list)) m_list = m_list * (max_m / np.max(m_list)) m_list = ...

class Voice_Model(tf.keras.Model): def init(self,config): self.config = config super(Voice_Model,self).init() self.lstm_1=tf.keras.layers.LSTM(config.num_filters,dropout=0.5,return_sequences=True,unroll=True) self.lstm_2 = tf.keras.layers.LSTM(config.num_filters, dropout=0.5, unroll=True) self.fc= tf.keras.layers.Dense(config.hidden_dim) self.dro = tf.keras.layers.Dropout(0.5) self.outlater = tf.keras.layers.Dense(config.num_classes,activation='softmax') def call(self,inputs,training=None,**kwargs): x = inputs x = self.lstm_1(x) x = self.lstm_2(x) x = self.fc(x) x = self.outlater(x) return x

这是一个 TensorFlow 2.x 中的一个声音识别模型的类定义。这个模型使用了两个 LSTM 层和一个全连接层来提取声音信号的特征，并使用 softmax 激活函数进行分类。在这个类中，__init__ 方法定义了模型的结构，包括...

def Dice_loss(inputs, target, beta=1, smooth = 1e-5): n, c, h, w = inputs.size() nt, ht, wt, ct = target.size() if h != ht and w != wt: inputs = F.interpolate(inputs, size=(ht, wt), mode="bilinear", align_corners=True) temp_inputs = torch.softmax(inputs.transpose(1, 2).transpose(2, 3).contiguous().view(n, -1, c),-1) temp_target = target.view(n, -1, ct) #--------------------------------------------# # 计算dice loss #--------------------------------------------# tp = torch.sum(temp_target[...,:-1] * temp_inputs, axis=[0,1]) fp = torch.sum(temp_inputs , axis=[0,1]) - tp fn = torch.sum(temp_target[...,:-1] , axis=[0,1]) - tp score = ((1 + beta ** 2) * tp + smooth) / ((1 + beta ** 2) * tp + beta ** 2 * fn + fp + smooth) dice_loss = 1 - torch.mean(score) return dice_loss

- inputs：模型的输出，是一个大小为 (n, c, h, w) 的张量，其中 n 表示 batch size，c 表示类别数，h 和 w 表示输入图片的高和宽。 - target：真实标签，是一个大小为 (n, h, w, ct) 的张量，其中 ct 表示标签的...

import numpy import scipy.special class NeuralNetwork(): def init(self,inputnodes,hiddennodes,outputnodes,learningrate): self.inodes=inputnodes self.hnodes=hiddennodes self.onodes=outputnodes self.lr=learningrate self.wih=numpy.random.normal(0.0,pow(self.hnodes,-0.5),(self.hnodes,self.inodes)) self.who=numpy.random.normal(0.0,pow(self.onodes,-0.5),(self.onodes,self.hnodes)) self.activation_function=lambda x:scipy.special.expit(x) pass def train(self,input_list,target_list): inputs=numpy.array(input_list,ndmin=2).T targets=numpy.array(target_list,ndmin=2).T hidden_inputs=numpy.dot(self.wih,inputs) hidden_outputs=self.activation_function(hidden_inputs) final_inputs=numpy.dot(self.who,hidden_outputs) final_outputs=self.activation_function(final_inputs) output_errors=targets-final_outputs hidden_errors=numpy.dot(self.who.T,output_errors) self.who+=self.lrnumpy.dot((output_errorsfinal_outputs(1.0-final_outputs)),numpy.transpose(hidden_outputs)) self.wih+=self.lrnumpy.dot((hidden_errorshidden_outputs(1.0-hidden_outputs)),numpy.transpose(inputs)) pass def query(self,input_list): inputs=numpy.array(input_list,ndmin=2).T hidden_inputs=numpy.dot(self.wih,inputs) hidden_outputs=self.activation_function(hidden_inputs) final_inputs=numpy.dot(self.who,hidden_outputs) final_outputs=self.activation_function(final_inputs) return final_outputs print('n')写一下注释

targets = numpy.array(target_list, ndmin=2).T # 计算隐藏层的输入和输出 hidden_inputs = numpy.dot(self.wih, inputs) hidden_outputs = self.activation_function(hidden_inputs) # 计算输出层的输入...

def define_generator(): # 定义输入 inputs = layers.Input(shape=(LATENT_DIM,)) x = layers.Dense(256)(inputs) x = layers.LeakyReLU()(x) x = layers.BatchNormalization()(x) x = layers.Dense(512)(x) x = layers.LeakyReLU()(x) x = layers.BatchNormalization()(x) x = layers.Dense(SEQ_LEN * NUM_CLASSES, activation='tanh')(x) outputs = layers.Reshape((SEQ_LEN, NUM_CLASSES))(x) # 定义模型 model = tf.keras.Model(inputs, outputs, name='generator') return model # 定义判别器模型 def define_discriminator(): # 定义输入 inputs = layers.Input(shape=(SEQ_LEN, NUM_CLASSES)) x = layers.Flatten()(inputs) x = layers.Dense(512)(x) x = layers.LeakyReLU()(x) x = layers.Dense(256)(x) x = layers.LeakyReLU()(x) # 注意这里输出为1，表示真假 outputs = layers.Dense(1, activation='sigmoid')(x) # 定义模型 model = tf.keras.Model(inputs, outputs, name='discriminator') return model # 定义GAN模型 def define_gan(generator, discriminator): # 将判别器设置为不可训练 discriminator.trainable = False # 定义输入 inputs = layers.Input(shape=(LATENT_DIM,)) # 生成音符和和弦 outputs = generator(inputs) # 判断音符和和弦是否为真实的 real_or_fake = discriminator(outputs) # 定义模型 model = tf.keras.Model(inputs, real_or_fake, name='gan') return model # 定义损失函数和优化器 def define_loss_and_optimizer(): loss_fn = tf.keras.losses.BinaryCrossentropy() generator_optimizer = tf.keras.optimizers.Adam(learning_rate=0.0002, beta_1=0.5) discriminator_optimizer = tf.keras.optimizers.Adam(learning_rate=0.0002, beta_1=0.5) return loss_fn, generator_optimizer, discriminator_optimizer

这段代码看起来像是在定义一个基于 GAN 的音乐生成模型。其中包含了三个函数，分别是生成器模型、判别器模型和 GAN 模型。生成器模型输入一个随机的噪音向量，输出一个符合规定长度和音符类型数量的音符和和弦序列。...

train with base lr in the first 100 epochs # and half the lr in the last 100 epochs To train with a base learning rate for the first 100 epochs and half the learning rate for the last 100 epochs, you can use a learning rate scheduler in PyTorch. Here's an example of how you can modify the training loop in your code: import torch import torch.nn as nn import torch.optim as optim from torch.optim.lr_scheduler import MultiStepLR # Define your model, criterion, and optimizer model = YourModel() criterion = nn.CrossEntropyLoss() optimizer = optim.SGD(model.parameters(), lr=0.01) # Define the number of epochs and the milestone epochs num_epochs = 200 milestones = [100] # Create a learning rate scheduler scheduler = MultiStepLR(optimizer, milestones=milestones, gamma=0.5) # Train the model for epoch in range(num_epochs): # Train with base lr for the first 100 epochs, and half the lr for the last 100 epochs if epoch >= milestones[0]: scheduler.step() for inputs, labels in train_loader: # Forward pass outputs = model(inputs) loss = criterion(outputs, labels) # Backward pass and optimization optimizer.zero_grad() loss.backward() optimizer.step() # Perform validation or testing after each epoch with torch.no_grad(): # Validation or testing code # Print training information print(f"Epoch [{epoch+1}/{num_epochs}], Loss: {loss.item()}, LR: {scheduler.get_last_lr()[0]}") # Save the model or perform other operations after training In this code snippet, we create a MultiStepLR scheduler and specify the milestones as [100] and gamma as 0.5. The learning rate is halved at the specified milestone epochs. Inside the training loop, we check if the current epoch is greater than or equal to the milestone epoch, and if so, we call scheduler.step() to update the learning rate. Remember to adjust the num_epochs and other hyperparameters according to your specific requirements. 翻译成中文

print(f"Epoch [{epoch+1}/{num_epochs}], Loss: {loss.item()}, LR: {scheduler.get_last_lr()[0]}") # 保存模型或进行其他操作在这段代码中，我们创建了一个MultiStepLR调度器，并将里程碑轮数设为[100]，...

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