训练BP神经网络对函数进行拟合答:clc,clear;P=-pi/2+0.1:pi/10:pi/2-0.1;T=tan(P);plot(P,T,'-*');[Pn,pps]=mapminmax(P,0,1); %p归一化[Tn,tps]=mapminmax(T,0,1); %t归一化net=newff(minmax(Pn),[5 1],{'tansig','purelin'},'trainlm');net.trainParam.show=10;net.trainParam.lr=0.05;net...