def activation_hook(self, grad): self.gradients = grad # extract gradient def get_activation_gradient(self): return self.gradients # extract the activation after the last ReLU def get_activation(self, x): return self.features(x)
时间: 2023-12-11 15:05:04 浏览: 26
这一个深度学习模型中的代码,用于提取激活函数的梯度和激活函数的输出。具体来说,这段代码定义了一个名为"activation_hook"的函数,用于提取梯度;另外还定义了两个函数"get_activation_gradient"和"get_activation",用于获取激活函数的梯度和输出,其中"get_activation"函数调用了模型的"features"函数来计算激活函数的输出。这些函数可以在训练过程中用于分析模型的性能和优化模型的参数。
相关问题
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.lr*numpy.dot((output_errors*final_outputs*(1.0-final_outputs)),numpy.transpose(hidden_outputs)) self.wih+=self.lr*numpy.dot((hidden_errors*hidden_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
以下是对代码的注释:
```python
import numpy
import scipy.special
class NeuralNetwork():
def __init__(self,inputnodes,hiddennodes,outputnodes,learningrate):
# 初始化神经网络的输入层、隐藏层、输出层的节点数以及学习率
self.inodes = inputnodes
self.hnodes = hiddennodes
self.onodes = outputnodes
self.lr = learningrate
# 初始化输入层到隐藏层和隐藏层到输出层的权重
# 对权重进行随机初始化,取值范围为均值为0,标准差为节点数的负平方根
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))
# 定义激活函数为 sigmoid 函数
self.activation_function = lambda x: scipy.special.expit(x)
def train(self,input_list,target_list):
# 将输入列表和目标列表转换为二维数组
inputs = numpy.array(input_list, ndmin=2).T
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)
# 计算输出层的输入和输出
final_inputs = numpy.dot(self.who, hidden_outputs)
final_outputs = self.activation_function(final_inputs)
# 计算输出层误差和隐藏层误差
output_errors = targets - final_outputs
hidden_errors = numpy.dot(self.who.T, output_errors)
# 更新隐藏层到输出层和输入层到隐藏层的权重
self.who += self.lr * numpy.dot((output_errors * final_outputs * (1.0 - final_outputs)), numpy.transpose(hidden_outputs))
self.wih += self.lr * numpy.dot((hidden_errors * hidden_outputs * (1.0 - hidden_outputs)), numpy.transpose(inputs))
def query(self,input_list):
# 将输入列表转换为二维数组
inputs = numpy.array(input_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)
# 计算输出层的输入和输出
final_inputs = numpy.dot(self.who, hidden_outputs)
final_outputs = self.activation_function(final_inputs)
# 返回最终输出
return final_outputs
# 创建神经网络实例
input_nodes = 3
hidden_nodes = 3
output_nodes = 3
learning_rate = 0.3
n = NeuralNetwork(input_nodes,hidden_nodes,output_nodes,learning_rate)
# 使用训练数据进行训练
training_data = [[0.1, 0.2, 0.3], [0.4, 0.5, 0.6], [0.7, 0.8, 0.9]]
for data in training_data:
n.train(data, data)
# 使用测试数据进行测试
test_data = [0.2, 0.5, 0.8]
print(n.query(test_data))
```
这个神经网络实现了一个简单的自编码器,训练数据和测试数据都是由一些简单的数字组成。
import pandas as pd import warnings import sklearn.datasets import sklearn.linear_model import matplotlib import matplotlib.font_manager as fm import matplotlib.pyplot as plt import numpy as np import seaborn as sns data = pd.read_excel(r'C:\Users\Lenovo\Desktop\data.xlsx') print(data.info()) fig = plt.figure(figsize=(10, 8)) sns.heatmap(data.corr(), cmap="YlGnBu", annot=True) plt.title('相关性分析热力图') plt.rcParams['axes.unicode_minus'] = False plt.rcParams['font.sans-serif'] = 'SimHei' plt.show() y = data['y'] x = data.drop(['y'], axis=1) print('************************输出新的特征集数据***************************') print(x.head()) from sklearn.model_selection import train_test_split x_train, x_test, y_train, y_test = train_test_split(x, y, test_size=0.2, random_state=42) def relu(x): output=np.maximum(0, x) return output def relu_back_propagation(derror_wrt_output,x): derror_wrt_dinputs = np.array(derror_wrt_output, copy=True) derror_wrt_dinputs[x <= 0] = 0 return derror_wrt_dinputs def activated(activation_choose,x): if activation_choose == 'relu': return relu(x) def activated_back_propagation(activation_choose, derror_wrt_output, output): if activation_choose == 'relu': return relu_back_propagation(derror_wrt_output, output) 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
这段代码存在两个问题:
1. 在import语句中没有使用逗号分隔符,应该在每个import语句之间添加逗号分隔符。
2. 在函数set_xy()的定义中,函数体没有缩进,应该在函数体内部添加缩进。
以下是修改后的代码:
```python
import pandas as pd, warnings
import sklearn.datasets, sklearn.linear_model
import matplotlib, matplotlib.font_manager as fm
import matplotlib.pyplot as plt
import numpy as np
import seaborn as sns
data = pd.read_excel(r'C:\Users\Lenovo\Desktop\data.xlsx')
print(data.info())
fig = plt.figure(figsize=(10, 8))
sns.heatmap(data.corr(), cmap="YlGnBu", annot=True)
plt.title('相关性分析热力图')
plt.rcParams['axes.unicode_minus'] = False
plt.rcParams['font.sans-serif'] = 'SimHei'
plt.show()
y = data['y']
x = data.drop(['y'], axis=1)
print('************************输出新的特征集数据***************************')
print(x.head())
from sklearn.model_selection import train_test_split
x_train, x_test, y_train, y_test = train_test_split(x, y, test_size=0.2, random_state=42)
def relu(x):
output=np.maximum(0, x)
return output
def relu_back_propagation(derror_wrt_output,x):
derror_wrt_dinputs = np.array(derror_wrt_output, copy=True)
derror_wrt_dinputs[x <= 0] = 0
return derror_wrt_dinputs
def activated(activation_choose,x):
if activation_choose == 'relu':
return relu(x)
def activated_back_propagation(activation_choose, derror_wrt_output, output):
if activation_choose == 'relu':
return relu_back_propagation(derror_wrt_output, output)
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
```