[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： f-3'D-{EKt  
net=newff([-1 2; 0 5],[3,1],{'tansig','purelin'},'traingd'); :
Wg-@d  
net.trainParam.show = 50; Y62u%':X  
net.trainParam.lr = 0.05; /MKNv'5&!%  
net.trainParam.epochs = 300; |O(-CDQe  
net.trainParam.goal = 1e-5; @q+cmJKv  
p = [-1 -1 2 2;0 5 0 5]; | 7 m5P
@X  
t = [-1 -1 1 1]; Du^x=;  
net=train(net,p,t); p:JRQT"A  
TRAINGD, Epoch 0/300, MSE 1.59423/1e-05, Gradient 2.76799/1e-10 p,w|=@=  
TRAINGD, Epoch 50/300, MSE 0.00236382/1e-05, Gradient 0.0495292/1e-10 hqs$yb  
TRAINGD, Epoch 100/300, MSE 0.000435947/1e-05, Gradient 0.0161202/1e-10 6h2x
~@  
TRAINGD, Epoch 150/300, MSE 8.68462e-05/1e-05, Gradient 0.00769588/1e-10 GG_^K#*  
TRAINGD, Epoch 200/300, MSE 1.45042e-05/1e-05, Gradient 0.00325667/1e-10 6Lg!Lodu  
TRAINGD, Epoch 211/300, MSE 9.64816e-06/1e-05, Gradient 0.00266775/1e-10 =! N _^cb  
TRAINGD, Performance goal met. U=F-]lD  
a = sim(net,p) F?b'L JS  
plot(p,t,p,a,'o') [A"H/Qztk  
但是为什么老是报错： qDRNtFa  
??? Input argument "net" is undefined. N.0HfYf