求大神帮忙看看，我写的基3蝶形运算程序到底哪里错了？

Question

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function [Xk,N]=JISAN(xn,L)
M=0;
while L>1
M=M+1;
L=fix(L/3);
end
N=3^M;
for m=0:2*(N/3-1);
Wn(m+1)=exp(-1j*2*pi*m/N);
W1=exp(-1j*2*pi/3);W2=exp(-1j*4*pi/3);
end
A=xn;
I=0;
for Q=0:9:N-10;
for J=0:2;
for k=0:3:9;
A(I+1)=xn(k+J+Q+1);
I=I+1;
end
end
end
for L=1:M;
B=3^(L-1);
for J=0:B-1;
P=3^(M-L)*J;
for K=J:3^L:N-1;
T=A(K+1)+A(K+B+1)*Wn(P+1)+A(K+2*B+1)*Wn(2*P+1);
A(K+B+1)=A(K+1)+A(K+B+1)*Wn(P+1)*W1+A(K+2*B+1)*Wn(2*P+1)*W2;
A(K+2*B+1)=A(K+1)+A(K+B+1)*Wn(P+1)*W2+A(K+2*B+1)*Wn(2*P+1)*W1;
A(K+1)=T;

         end
    end

end
Xk=A;
如果给一个正弦信号用上面程序处理，出来的波形怎么跟随机信号似的！，