各位大蝦，我在網(wǎng)上看到的教程里的一個程序段，本來想要試試看的： ,lL0'$k~  
net=newff([-1 2; 0 5],[3,1],{'tansig','purelin'},'traingd'); CIO&VK  
net.trainParam.show = 50; ,^AkfOY7"  
net.trainParam.lr = 0.05; Rjm5{aa-  
net.trainParam.epochs = 300; }KS[(Q  
net.trainParam.goal = 1e-5; DC[-<:B  
p = [-1 -1 2 2;0 5 0 5]; MttVgNV  
t = [-1 -1 1 1]; J]fjg%C2m  
net=train(net,p,t); |JuXOcr4  
TRAINGD, Epoch 0/300, MSE 1.59423/1e-05, Gradient 2.76799/1e-10 96MRnj*Y[  
TRAINGD, Epoch 50/300, MSE 0.00236382/1e-05, Gradient 0.0495292/1e-10 R:^GNra;  
TRAINGD, Epoch 100/300, MSE 0.000435947/1e-05, Gradient 0.0161202/1e-10 _W]3_1Lu  
TRAINGD, Epoch 150/300, MSE 8.68462e-05/1e-05, Gradient 0.00769588/1e-10 b*?="%eE(  
TRAINGD, Epoch 200/300, MSE 1.45042e-05/1e-05, Gradient 0.00325667/1e-10 U{i9h6b"18  
TRAINGD, Epoch 211/300, MSE 9.64816e-06/1e-05, Gradient 0.00266775/1e-10 ;v8,r#4  
TRAINGD, Performance goal met. }v=q6C#Q>  
a = sim(net,p) Q\ro )r  
plot(p,t,p,a,'o') \$riwL  
但是為什么老是報錯： If]g6 B.=  
??? Input argument "net" is undefined. /PHktSG