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;
9 ?, s5 |" g) |' h( |, ]/ r6 @' Va=1e-6;
b=1e-6;
% J7 ^; n/ h" ?/ @# j; k" QD=0.25;
lamda=1.225e-9/sqrt(U*(1+0.9783e-6*U));
A=pi*a/lamda*D;
! S* a7 J, J$ ^  t0 }# u8 UB=pi*(a+b)/lamda*D;
for(i=0;i<=200;i++)
, N- E0 W4 V3 S  P  i: r6 U5 N{x=5e-5*(2*rand-1);
y=4e-5*(2*rand-1);
, k  _8 O7 k7 J0 kPw=(sin(A*x))^2*(cos(B*x))^2/(A*x)^2<=1;
M=rand;
$ l9 Y3 q$ X- Y& L0 e5 q  Tif(Pw>=M)
plot(x,y,'.r','markersize',10);
pause(200);}

rergr

再看看别人是怎么说的

land

U=1000;
; h1 o3 b7 M7 _* c9 `a=1e-6;
b=1e-6;
D=0.25;
lamda=1.225e-9/sqrt(U*(1+0.9783e-6*U));
2 ?; A6 t& ?5 O+ E2 a: oA=pi*a/lamda*D;
B=pi*(a+b)/lamda*D;
hold on
: G' ]9 E0 z3 J5 |& A6 d4 ^for i=0:200
x=5e-5*(2*rand-1);
, A+ d& S8 `4 W  w* e0 G1 H! Yy=4e-5*(2*rand-1);
Pw=(sin(A*x))^2*(cos(B*x))^2/(A*x)^2<=1;
( w( g8 F, @4 O; S, t) ], r# `. TM=rand;
% I9 p# X8 e+ p; H0 ?6 S4 `4 wif Pw>=M
9 r- c) r2 x! S" Zplot(x,y,'.r','markersize',10)
end
' X/ N" l7 A3 n* spause(.02)
end