[求助]新手求助~（关于初级的神经网络问题） [复制链接]

各位大虾，我在网上看到的教程里的一个程序段，本来想要试试看的： ;WIL?[;w  
net=newff([-1 2; 0 5],[3,1],{'tansig','purelin'},'traingd'); (l22p  
net.trainParam.show = 50; <$liWAGX\  
net.trainParam.lr = 0.05; dE5DH~ldV  
net.trainParam.epochs = 300;  =erA.u  
net.trainParam.goal = 1e-5; *8p\.za1  
p = [-1 -1 2 2;0 5 0 5]; 6RZ[X[R[}  
t = [-1 -1 1 1]; Q:+Y-&||"  
net=train(net,p,t); 3&*0n^g  
TRAINGD, Epoch 0/300, MSE 1.59423/1e-05, Gradient 2.76799/1e-10 Y51XpcXQ  
TRAINGD, Epoch 50/300, MSE 0.00236382/1e-05, Gradient 0.0495292/1e-10 C#r_qn  
TRAINGD, Epoch 100/300, MSE 0.000435947/1e-05, Gradient 0.0161202/1e-10 sF;1)7]Pq  
TRAINGD, Epoch 150/300, MSE 8.68462e-05/1e-05, Gradient 0.00769588/1e-10 @];#4O  
TRAINGD, Epoch 200/300, MSE 1.45042e-05/1e-05, Gradient 0.00325667/1e-10 i7~oZ)w  
TRAINGD, Epoch 211/300, MSE 9.64816e-06/1e-05, Gradient 0.00266775/1e-10 Xi5kE'_  
TRAINGD, Performance goal met. hE:P'O1  
a = sim(net,p) "sFdr
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plot(p,t,p,a,'o') whNRUOK:  
但是为什么老是报错： ;J\{r$q  
??? Input argument "net" is undefined. 8
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