[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： ]`K2N  
net=newff([-1 2; 0 5],[3,1],{'tansig','purelin'},'traingd'); ~a:  
net.trainParam.show = 50; qna8|3
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net.trainParam.lr = 0.05; NOva'qk  
net.trainParam.epochs = 300; "x-j~u?  
net.trainParam.goal = 1e-5; +rd+0 `}C  
p = [-1 -1 2 2;0 5 0 5]; 29KiuP  
t = [-1 -1 1 1]; 0;k# *#w  
net=train(net,p,t); cr3^6HB  
TRAINGD, Epoch 0/300, MSE 1.59423/1e-05, Gradient 2.76799/1e-10 py4 h(04u  
TRAINGD, Epoch 50/300, MSE 0.00236382/1e-05, Gradient 0.0495292/1e-10 WcAkCH!L  
TRAINGD, Epoch 100/300, MSE 0.000435947/1e-05, Gradient 0.0161202/1e-10 b;n[mk  
TRAINGD, Epoch 150/300, MSE 8.68462e-05/1e-05, Gradient 0.00769588/1e-10 xpt:BBo  
TRAINGD, Epoch 200/300, MSE 1.45042e-05/1e-05, Gradient 0.00325667/1e-10 CrLrw T  
TRAINGD, Epoch 211/300, MSE 9.64816e-06/1e-05, Gradient 0.00266775/1e-10 HtFDlvdy]  
TRAINGD, Performance goal met. .]^?<bG  
a = sim(net,p) s_Sk0}e  
plot(p,t,p,a,'o') icgfB-1|i  
但是为什么老是报错： O-^Ma-}  
??? Input argument "net" is undefined. U6K|fYN`