[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： Ojh\H  
net=newff([-1 2; 0 5],[3,1],{'tansig','purelin'},'traingd'); ?!uj8&yyf  
net.trainParam.show = 50; EAdr}io  
net.trainParam.lr = 0.05;  3ih3O  
net.trainParam.epochs = 300; 1TOT}h5  
net.trainParam.goal = 1e-5; oy;g;dtq  
p = [-1 -1 2 2;0 5 0 5]; Dc2U+U(J  
t = [-1 -1 1 1]; {\SJr:  
net=train(net,p,t); b3zxiq x  
TRAINGD, Epoch 0/300, MSE 1.59423/1e-05, Gradient 2.76799/1e-10 [i9.#*  
TRAINGD, Epoch 50/300, MSE 0.00236382/1e-05, Gradient 0.0495292/1e-10 0LjF$3GpZ  
TRAINGD, Epoch 100/300, MSE 0.000435947/1e-05, Gradient 0.0161202/1e-10 T3JM8  
TRAINGD, Epoch 150/300, MSE 8.68462e-05/1e-05, Gradient 0.00769588/1e-10 VV$$t;R/
 
TRAINGD, Epoch 200/300, MSE 1.45042e-05/1e-05, Gradient 0.00325667/1e-10 S4salpz  
TRAINGD, Epoch 211/300, MSE 9.64816e-06/1e-05, Gradient 0.00266775/1e-10 y<h~jz#hkq  
TRAINGD, Performance goal met. vC# *w,  
a = sim(net,p) <r8sZrY  
plot(p,t,p,a,'o') 4@Q`8N.  
但是为什么老是报错： bXx2]E227  
??? Input argument "net" is undefined. R
TLA*