[交流] 【matlab】二元 分段 函数怎么绘图？

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g=0;
lambda0=1.55;
k0=2*pi/lambda0;
c=3*10^8;
n1=1.4949;
E1=n1^2;

a=6.004;
Na=0.08837;
n3=1.465;
n5=1.465;
E3=n3^2;
E5=n5^2;

kx=k0*Na;
k3x=(k0^2*(E1-E3)-kx^2)^1/2;
k5x=(k0^2*(E1-E5)-kx^2)^1/2;



b=6.004
Nb=0.08932
c=3*10^8;
n2=1.465;
n4=1.465;
E2=n2^2;
E4=n4^2;

ky=k0*Nb;
k2y=(k0^2*(E1-E2)-ky^2)^1/2;
k4y=(k0^2*(E1-E4)-ky^2)^1/2;

z=cos(1/2*kx*a+g)*exp(k3x*(x+1/2*a)).*(x<=-1/2*a)+...
cos(kx*x-g).*(x>=-1/2*a&x<=1/2*a)+...
cos(1/2*kx*a-g)*exp(-k5x*(x-1/2*a)).*(x>1/2*a)+...
cos(1/2*ky*b+g)*exp(k2y*(y+1/2*b)).*(y<=-1/2*b)+...
cos(ky*y-g).*(y>=-1/2*b&y<=1/2*b)+...
cos(1/2*ky*b-g)*exp(-k4y*(y-1/2*b)).*(y>1/2*b);
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