转载一个实现分数傅立叶变换的matlab程序,作者信息在程序中有。
e6es0D[>5 ]*h&hsS0 function FF=frft_PXJ(N,alpha);
p
d%LL?O %matrix
B$EK_@M % FF is the kernel matrix of fractional Fourier transform
A@{ !:_55 % \copyright: zjliu
@>9A$w$H|a % Author's email:
zjliu2001@163.com Q~CpP9% Ts=sqrt(2*pi/N); t=-(N-1)/2:(N-1)/2; t=t'; t=t*Ts;
$@4e(Zrmo variance=N/2/pi; HH=zeros(N); HH(:,1)=1; HH(:,2)=2*t;
`w(sXkeaI for k=3:N;
:6sGX p HH(:,k)=HH(:,k-1).*t*2-2*(k-2)*HH(:,k-2);
S&`O\!NF end
4}PeP^pj HH(:,1)=1/sqrt(sqrt(variance))*HH(:,1).*exp(-t.*t/2);
*kV#)j for k=2:N;
bAdAp W HH(:,k)=exp(-t.*t/2).*HH(:,k)/sqrt(2.^(k-1)*...
u;{T2T
factorial(k-1)*sqrt(variance));
m4\g o end
?-M)54b\ if mod(N,2)==1;
t;~-_{ W=0:N-1; k=exp(-i*alpha*W); D=diag(k);
-q|*M:R else
7vdHR\#;$ W=0:N-2; W=cat(2,W,[N]); k=exp(-i*alpha*W); D=diag(k);
n+S&!PB end
GHqBnE{B FF=Ts*HH*D*HH'*2;
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