[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： eC1c`@C:  
net=newff([-1 2; 0 5],[3,1],{'tansig','purelin'},'traingd'); o@V/37!  
net.trainParam.show = 50; MrygEC 5  
net.trainParam.lr = 0.05; l#(g&x6J  
net.trainParam.epochs = 300; F@*r%[S/  
net.trainParam.goal = 1e-5; cqU/Y_%l'  
p = [-1 -1 2 2;0 5 0 5]; U=*q;$L#  
t = [-1 -1 1 1]; (Gb{ckzs  
net=train(net,p,t);
^O\
1v  
TRAINGD, Epoch 0/300, MSE 1.59423/1e-05, Gradient 2.76799/1e-10 l9Cy30O6  
TRAINGD, Epoch 50/300, MSE 0.00236382/1e-05, Gradient 0.0495292/1e-10 0i1?S6]d-  
TRAINGD, Epoch 100/300, MSE 0.000435947/1e-05, Gradient 0.0161202/1e-10 p`V9+CA  
TRAINGD, Epoch 150/300, MSE 8.68462e-05/1e-05, Gradient 0.00769588/1e-10 iF2IR{h  
TRAINGD, Epoch 200/300, MSE 1.45042e-05/1e-05, Gradient 0.00325667/1e-10 .dq.F#2B;  
TRAINGD, Epoch 211/300, MSE 9.64816e-06/1e-05, Gradient 0.00266775/1e-10 V:$1o  
TRAINGD, Performance goal met. _\V{X}ftqa  
a = sim(net,p) kTe<1^,m  
plot(p,t,p,a,'o') 5D@Q1
 
但是为什么老是报错： SEn8t"n  
??? Input argument "net" is undefined. Mh@ylp+q