咱们就是说 也不知道写了个啥 好像就是吧公式全都写上去了 先交个作业吧…有时间在更正一下…
x1=1
x2=1
x3=1
t1=t2=1
w41=w42=w43=w51=w52=w53=w61=w62=w63=w71=w72=w73=1
w84=w85=w86=w87=w94=w95=w96=w97=1
n=0.1
a4=x1*w41+x2*w42+x3*w43
a5=x1*w51+x2*w52+x3*w53
a6=x1*w61+x2*w62+x3*w63
a7=x1*w71+x2*w72+x3*w73
y1=w84*a4+w85*a5+w86*a6+w87*a7
y2=w94*a4+w95*a5+w96*a6+w97*a7
Loss=(y1-t1)**2+(y2-t2)**2
delta84=2*(y1-t1)*(1-y1)*y1*a4
delta85=2*(y1-t1)*(1-y1)*y1*a5
delta86=2*(y1-t1)*(1-y1)*y1*a6
delta87=2*(y1-t1)*(1-y1)*y1*a7
delta94=2*(y2-t2)*(1-y2)*y1*a4
delta95=2*(y2-t2)*(1-y2)*y1*a5
delta96=2*(y2-t2)*(1-y2)*y1*a6
delta97=2*(y2-t2)*(1-y2)*y1*a7
w84=w84-n*delta84
w85=w85-n*delta85
w86=w86-n*delta86
w87=w87-n*delta87
w94=w94-n*delta94
w95=w95-n*delta95
w96=w96-n*delta96
w97=w97-n*delta97
delta41=2*(y1-t1)*y1*(1-y1)*w84+2*(y2-t2)*y2*(1-y2)*w94*a4*(1-a4)*x1
delta42=2*(y1-t1)*y1*(1-y1)*w84+2*(y2-t2)*y2*(1-y2)*w94*a4*(1-a4)*x2
delta43=2*(y1-t1)*y1*(1-y1)*w84+2*(y2-t2)*y2*(1-y2)*w94*a4*(1-a4)*x3
delta51=2*(y1-t1)*y1*(1-y1)*w85+2*(y2-t2)*y2*(1-y2)*w95*a5*(1-a5)*x1
delta52=2*(y1-t1)*y1*(1-y1)*w85+2*(y2-t2)*y2*(1-y2)*w95*a5*(1-a5)*x2
delta53=2*(y1-t1)*y1*(1-y1)*w85+2*(y2-t2)*y2*(1-y2)*w95*a5*(1-a5)*x3
delta61=2*(y1-t1)*y1*(1-y1)*w86+2*(y2-t2)*y2*(1-y2)*w96*a6*(1-a6)*x1
delta62=2*(y1-t1)*y1*(1-y1)*w86+2*(y2-t2)*y2*(1-y2)*w96*a6*(1-a6)*x2
delta63=2*(y1-t1)*y1*(1-y1)*w86+2*(y2-t2)*y2*(1-y2)*w96*a6*(1-a6)*x3
delta71=2*(y1-t1)*y1*(1-y1)*w87+2*(y2-t2)*y2*(1-y2)*w97*a7*(1-a7)*x1
delta72=2*(y1-t1)*y1*(1-y1)*w87+2*(y2-t2)*y2*(1-y2)*w97*a7*(1-a7)*x2
delta73=2*(y1-t1)*y1*(1-y1)*w87+2*(y2-t2)*y2*(1-y2)*w97*a7*(1-a7)*x3
