matlab仿真代码总是出问题。提示说for循环那行有问题，找不出来

three

U=1000;
a=1e-6;
' Y- k! S6 G3 _7 Db=1e-6;
D=0.25;
lamda=1.225e-9/sqrt(U*(1+0.9783e-6*U));
A=pi*a/lamda*D;
3 K! o4 r6 J: Z! D3 H3 _B=pi*(a+b)/lamda*D;
- |# H7 ?0 p4 O: v0 h) x: ?for(i=0;i<=200;i++)
9 }( c& T$ \8 o" ]2 V{x=5e-5*(2*rand-1);
" r1 e! k( X6 ~& F! r8 a! t: ]y=4e-5*(2*rand-1);
) n  }) e! h6 O/ Y  P, j/ pPw=(sin(A*x))^2*(cos(B*x))^2/(A*x)^2<=1;
M=rand;
- u0 S4 X( v) fif(Pw>=M)
plot(x,y,'.r','markersize',10);
pause(200);}

land

U=1000;
a=1e-6;
b=1e-6;
D=0.25;
lamda=1.225e-9/sqrt(U*(1+0.9783e-6*U));
0 y* Q2 B/ [4 {A=pi*a/lamda*D;
. L2 X: b4 L" d7 }B=pi*(a+b)/lamda*D;
, s& B" U$ B, k. G# ^- ]hold on
for i=0:200
x=5e-5*(2*rand-1);
y=4e-5*(2*rand-1);
: A" X: M; p4 {0 ZPw=(sin(A*x))^2*(cos(B*x))^2/(A*x)^2<=1;
5 n9 C/ C( Z$ w4 i, p+ v& hM=rand;
+ S) K: K5 @/ rif Pw>=M
9 n9 [# V1 U; q8 ]+ tplot(x,y,'.r','markersize',10)
end
: @& e" i6 i7 y8 m3 a4 Upause(.02)
9 }2 G/ ^( U6 l3 _! U, \# vend

rergr

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