谁可以用matlab 编写一个程序，要求所得运行结果能够形象地演示出一个时变电磁场随时间变化的情况。急！

z=linspace(0,50,501)

n=linspace(0,0,501)

count=1

for time=linspace(0,6*pi*10^(-8),200)

Ex=2*cos(10^8*time-z/sqrt(3))

Ey=-cos(10^8*time-z/sqrt(3)-pi/2)

Hx=4.59/4*cos(10^8*time-z/运弯派sqrt(3)-pi/2)%振幅扩大250倍

Hy=9.19/4*cos(10^8*time-z/sqrt(3)) %振幅扩旁贺大250倍

plot3(z,Ex,Ey,z,Hx,Hy,z,n,n,n,linspace...

(-2.5,2.5,501),n,'闹余r',n,n,linspace(-2.5,2.5,501),'r')

axis([0 50 -2.5 2.5 -2.5 2.5])

grid on

N(count)=getframe

count=count+1

end

movie(N,1,30)

x=-2:0.5:2y=-2:0.5:2

[X,Y]=meshgrid(x,y)

BX=-Y./((X).^2+Y.^2)

BY=X./((X).^2+Y.^2)

quiver(X,Y,BX,BY,0.8)

title('直导线的磁场分布'衫档搭),hold on

a=0b=0

plot(a,b,'ro'或拿蠢昌,a,b,'r+')

1

clearclfq=2e-6k=9e9a=2.0b=0x=-6:0.6:6y=x

[X,Y]=meshgrid(x,y)

rp=sqrt((X-a).^2+(Y-b).^2)rm=sqrt((X+a).^2+(Y+b).^2)

V=q*k*(1./rp-1./rm)

[Ex,Ey]=gradient(-V)

AE=sqrt(Ex.^2+Ey.^2)Ex=Ex./AEEy=Ey./AE

cv=linspace(min(min(V)),max(max(V)),51)

contour(X,Y,V,cv,'r-')

%axis('毁扰州square')

title('\fontname{ 宋体 }\fontsize{11} 电偶极子的电场线与等势纤蔽线 '),hold on

quiver(X,Y,Ex,Ey,0.6,'g')

plot(a,b,'bo',a,b,'g+'李掘)

plot(-a,-b,'bo',-a,-b,'w-')

xlabel('x')ylabel('y'),hold off

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