[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： 3RF`F i  
net=newff([-1 2; 0 5],[3,1],{'tansig','purelin'},'traingd'); Us.k,  
net.trainParam.show = 50; },@ex  
net.trainParam.lr = 0.05; 0Y
C|;`J  
net.trainParam.epochs = 300; "d`u#YmR  
net.trainParam.goal = 1e-5; x!6<7s  
p = [-1 -1 2 2;0 5 0 5]; n1x"B>3  
t = [-1 -1 1 1]; y'!"GrbZ  
net=train(net,p,t); >Q=Q%~  
TRAINGD, Epoch 0/300, MSE 1.59423/1e-05, Gradient 2.76799/1e-10 ~e&O?X  
TRAINGD, Epoch 50/300, MSE 0.00236382/1e-05, Gradient 0.0495292/1e-10 \EXa 9X2  
TRAINGD, Epoch 100/300, MSE 0.000435947/1e-05, Gradient 0.0161202/1e-10 k=cDPu -  
TRAINGD, Epoch 150/300, MSE 8.68462e-05/1e-05, Gradient 0.00769588/1e-10 yJ="dEn>i"  
TRAINGD, Epoch 200/300, MSE 1.45042e-05/1e-05, Gradient 0.00325667/1e-10 xf{ZwS%X  
TRAINGD, Epoch 211/300, MSE 9.64816e-06/1e-05, Gradient 0.00266775/1e-10 kA> e*6  
TRAINGD, Performance goal met. ,M~> t7+  
a = sim(net,p) v o4U%  
plot(p,t,p,a,'o') ,pY:kQ  
但是为什么老是报错： kE:{#>[Uz  
??? Input argument "net" is undefined. ExM VGe