求指导,我用你的代码运行一个不一样的东西,结果很失望![]() import java.util.Random; public class BpDeep{ public double[][] layer;//神经网络各层节点 public double[][] layerErr;//神经网络各节点误差 public double[][][] layer_weight;//各层节点权重 public double[][][] layer_weight_delta;//各层节点权重动量 public double mobp;//动量系数 public double rate;//学习系数 public BpDeep(int[] layernum, double rate, double mobp){ this.mobp = mobp; this.rate = rate; layer = new double[layernum.length][]; layerErr = new double[layernum.length][]; layer_weight = new double[layernum.length][][]; layer_weight_delta = new double[layernum.length][][]; Random random = new Random(); for(int l=0;l<layernum.length;l++){ layer[l]=new double[layernum[l]]; layerErr[l]=new double[layernum[l]]; if(l+1<layernum.length){ layer_weight[l]=new double[layernum[l]+1][layernum[l+1]]; layer_weight_delta[l]=new double[layernum[l]+1][layernum[l+1]]; for(int j=0;j<layernum[l]+1;j++) for(int i=0;i<layernum[l+1];i++) layer_weight[l][j][i]=random.nextDouble();//随机初始化权重 } } } //逐层向前计算输出 public double[] computeOut(double[] in){ for(int l=1;l<layer.length;l++){ for(int j=0;j<layer[l].length;j++){ double z=layer_weight[l-1][layer[l-1].length][j]; for(int i=0;i<layer[l-1].length;i++){ layer[l-1][i]=l==1?in[i]:layer[l-1][i]; z+=layer_weight[l-1][i][j]*layer[l-1][i]; } layer[l][j]=1/(1+Math.exp(-z)); } } return layer[layer.length-1]; } //逐层反向计算误差并修改权重 public void updateWeight(double[] tar){ int l=layer.length-1; for(int j=0;j<layerErr[l].length;j++) layerErr[l][j]=layer[l][j]*(1-layer[l][j])*(tar[j]-layer[l][j]); while(l-->0){ for(int j=0;j<layerErr[l].length;j++){ double z = 0.0; for(int i=0;i<layerErr[l+1].length;i++){ z=z+l>0?layerErr[l+1][i]*layer_weight[l][j][i]:0; layer_weight_delta[l][j][i]= mobp*layer_weight_delta[l][j][i]+rate*layerErr[l+1][i]*layer[l][j];//隐含层动量调整 layer_weight[l][j][i]+=layer_weight_delta[l][j][i];//隐含层权重调整 if(j==layerErr[l].length-1){ layer_weight_delta[l][j+1][i]= mobp*layer_weight_delta[l][j+1][i]+rate*layerErr[l+1][i];//截距动量调整 layer_weight[l][j+1][i]+=layer_weight_delta[l][j+1][i];//截距权重调整 } } layerErr[l][j]=z*layer[l][j]*(1-layer[l][j]);//记录误差 } } } public void train(double[] in, double[] tar){ double[] out = computeOut(in); updateWeight(tar); } } import java.util.Arrays; public class MyBPtest1{ public static void main(String[] args){ //初始化神经网络的基本配置 //第一个参数是一个整型数组,表示神经网络的层数和每层节点数,比如{3,10,10,10,10,2}表示输入层是3个节点,输出层是2个节点,中间有4层隐含层,每层10个节点 /////////第二个参数是学习步长(过小会使收敛速度太慢;过大则会使预测不准,跳过一些细节), /////////第三个参数是动量系数(使波动小的预测重新振荡起来) BpDeep bp = new BpDeep(new int[]{5,5,1}, 0.15, 0.9); ////////对于输入样本如果只有一个数。没关系,大不了{,}第二项里的data和target全为0,,,,!!!!这理解是错误 ////////因为我们设定了输入层为2,才会有两个输入({,},{,}}这样的东西;同理输入层也为如此 ////////所以说如果是5个输入,一个输出对于data就{{,,,,},{,,,,}。。。。。。};;;;;对于target{,,,,} double[][] data = new double[][]{{192,195,194,193,193}, {195,194,193,193,195},{194,193,193,195,201}, {193,193,195,201,205},{193,195,201,205,205}, {195,201,205,205,203},{201,205,205,203,203}, {205,205,203,203,202},{205,203,203,202,206}, {203,203,202,206,204},{203,202,206,204,204}, {202,206,204,204,203},{206,204,204,203,199}, {204,204,203,199,195},{204,203,199,195,182}, {203,199,195,182,179},{199,195,182,179,178}, {195,182,179,178,176},{182,179,178,176,175}, {179,178,176,175,173},{178,176,175,173,175}, {176,175,173,175,182},{175,173,175,182,183}, {173,175,182,183,185},{175,182,183,185,179}}; //设置目标数据,对应4个坐标数据的分类 double[][] target = new double[][]{{195},{201},{205},{205},{203}, {203},{202},{206},{204},{204},{203},{199},{195},{182},{179}, {178},{176},{175},{173},{175},{182},{183},{185},{179},{182}}; //迭代训练5000次 ///////这里我们没有设置训练到了某一精确度自动停止,而是实打实的训练这些次数 for(int n=0;n<5000;n++) for(int i=0;i<data.length;i++) bp.train(data[i], target[i]); //根据训练结果来检验样本数据 for(int j=0;j<data.length;j++){ double[] result = bp.computeOut(data[j]); System.out.println(Arrays.toString(data[j])+":"+Arrays.toString(result)); } //根据训练结果来预测一条新数据的分类 double[] x = new double[]{192,195,194,193,193}; double[] result = bp.computeOut(x); System.out.println(Arrays.toString(x)+":"+Arrays.toString(result)); } } |