[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： T$RVz   
net=newff([-1 2; 0 5],[3,1],{'tansig','purelin'},'traingd'); _]E H~;  
net.trainParam.show = 50; fA{[H:*}G  
net.trainParam.lr = 0.05; } QVREj  
net.trainParam.epochs = 300; N=]2vyh  
net.trainParam.goal = 1e-5; ,_?P[~1  
p = [-1 -1 2 2;0 5 0 5]; uH7$/  
t = [-1 -1 1 1]; :_E=&4&g  
net=train(net,p,t); T~@$WM(  
TRAINGD, Epoch 0/300, MSE 1.59423/1e-05, Gradient 2.76799/1e-10 c193Or'6Y  
TRAINGD, Epoch 50/300, MSE 0.00236382/1e-05, Gradient 0.0495292/1e-10 gM~
dPM|  
TRAINGD, Epoch 100/300, MSE 0.000435947/1e-05, Gradient 0.0161202/1e-10 ^}vLZA  
TRAINGD, Epoch 150/300, MSE 8.68462e-05/1e-05, Gradient 0.00769588/1e-10 $a|C/s+}7>  
TRAINGD, Epoch 200/300, MSE 1.45042e-05/1e-05, Gradient 0.00325667/1e-10 mc
vd/  
TRAINGD, Epoch 211/300, MSE 9.64816e-06/1e-05, Gradient 0.00266775/1e-10 tfW*(oU  
TRAINGD, Performance goal met. OPHf9T3H  
a = sim(net,p) wN'Q\l+  
plot(p,t,p,a,'o') N]f"+  
但是为什么老是报错： 'au7rX(  
??? Input argument "net" is undefined. rvrv[^a(