人工智能作业1
import math from pandas import DataFrame def sigmoid(x):#激活函数 return 1/(1+math.exp(-x)) x1=[0.29,0.50,0.00,0.21,0.10,0.06,0.13,0.24,0.28] x2=[0.23,0.62,0.53,0.53,0.33,0.15,0.03,0.23,0.03] y=[0.14,0.64,0.28,0.33,0.12,0.03,0.02,0.11,0.08] yita=0.1 for i in range(0,9): #中间层神经元输入和输出层神经元输入 Net_in = DataFrame(0.6,index=['input1','input2','theata'],columns=['a']) Out_in = DataFrame(0,index=['input1','input2','input3','input4','theata'],columns=['a']) Net_in.iloc[0] = x1[i] Net_in.iloc[1] = x2[i] Net_in.iloc[2,0] = -1 Out_in.iloc[4,0] = -1 #中间层和输出层神经元权值 W_mid=DataFrame(0.5,index=['input1','input2','theata'],columns=['mid1','mid2','mid3','mid4']) W_out=DataFrame(0.5,index=['input1','input2','input3','input4','theata'],columns=['a']) W_mid_delta=DataFrame(0,index=['input1','input2','theata'],columns=['mid1','mid2','mid3','mid4']) W_out_delta=DataFrame(0,index=['input1','input2','input3','input4','theata'],columns=['a']) #中间层的输出 for i in range(0,4): Out_in.iloc[i,0] = sigmoid(sum(W_mid.iloc[:,i]*Net_in.iloc[:,0])) #输出层的输出/网络输出 res = sigmoid(sum(Out_in.iloc[:,0]*W_out.iloc[:,0])) error = abs(res-y[i]) #输出层权值变化量 W_out_delta.iloc[:,0] = yita*res*(1-res)*(y[i]-res)*Out_in.iloc[:,0] W_out_delta.iloc[4,0] = -(yita*res*(1-res)*(y[i]-res)) W_out = W_out + W_out_delta #输出层权值更新 #中间层权值变化量 for i in range(0,4): W_mid_delta.iloc[:,i] = yita*Out_in.iloc[i,0]*(1-Out_in.iloc[i,0])*W_out.iloc[i,0]*res*(1-res)*(y[i]-res)*Net_in.iloc[:,0] W_mid_delta.iloc[2,i] = -(yita*Out_in.iloc[i,0]*(1-Out_in.iloc[i,0])*W_out.iloc[i,0]*res*(1-res)*(y[i]-res)) W_mid = W_mid + W_mid_delta #中间层权值更新 new_x1 = [0.38, 0.29] new_x2 = [0.49, 0.47] for i in range(0,2): Net_in = DataFrame(0.6,index=['input1','input2','theata'],columns=['a']) Out_in = DataFrame(0,index=['input1','input2','input3','input4','theata'],columns=['a']) Net_in.iloc[0] = new_x1[i] Net_in.iloc[1] = new_x2[i] Net_in.iloc[2,0] = -1 Out_in.iloc[4,0] = -1 for i in range(0,4):#中间层的输出 Out_in.iloc[i,0] = sigmoid(sum(W_mid.iloc[:,i]*Net_in.iloc[:,0])) res = sigmoid(sum(Out_in.iloc[:,0]*W_out.iloc[:,0]))#输出层的输出 print(res)

2
import numpy import scipy.special import scipy.misc import matplotlib.pyplot import scipy.ndimage import math import pandas as pd from pandas import DataFrame,Series 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) hidden_outputs1=numpy.append(hidden_outputs,-1) 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') input_nodes=2 hidden_nodes=3 output_nodes=1 learning_rate=0.5 n=NeuralNetwork(input_nodes,hidden_nodes,output_nodes,learning_rate) training_data_file=open(r'D:\Computer Class\AI\3.3 data_te.txt') training_data_list=training_data_file.readlines(); training_data_file.close() for record in training_data_list[1:]: all_values=record.split(',') inputs=(numpy.asfarray(all_values[0:2])) targets=numpy.zeros(output_nodes) targets[0]=all_values[2] n.train(inputs,targets) pass test_data_file=open(r'D:\Computer Class\AI\3.3 data_te.txt') test_data_list=test_data_file.readlines() test_data_file.close() scorecard=[] total=0 correct=0 for record in test_data_list[1:]: total+=1 all_values=record.split(',') correct_label=all_values[2] inputs=(numpy.asfarray(all_values[0:2])) outputs=n.query(inputs) print(outputs)
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