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。
%5A+V0D0' D ;_ MPN[ function FF=frft_PXJ(N,alpha);
AKRTBjG"
%matrix
VxXzAeM % FF is the kernel matrix of fractional Fourier transform
;~\MZYs3m % \copyright: zjliu
qt;y2gf= % Author's email:
zjliu2001@163.com tPGJ<30 Ts=sqrt(2*pi/N); t=-(N-1)/2:(N-1)/2; t=t'; t=t*Ts;
"V$Bnz\n variance=N/2/pi; HH=zeros(N); HH(:,1)=1; HH(:,2)=2*t;
yq NzdzX for k=3:N;
U
)l,'y2 HH(:,k)=HH(:,k-1).*t*2-2*(k-2)*HH(:,k-2);
qfK` MhA} end
&'DU0c& HH(:,1)=1/sqrt(sqrt(variance))*HH(:,1).*exp(-t.*t/2);
r%.do;5 for k=2:N;
E5N{j4\F HH(:,k)=exp(-t.*t/2).*HH(:,k)/sqrt(2.^(k-1)*...
V 2i@.@$j factorial(k-1)*sqrt(variance));
]@0NO;bK>F end
=<NljOR4` if mod(N,2)==1;
tc!wLnhG W=0:N-1; k=exp(-i*alpha*W); D=diag(k);
Ldl 5zc else
Ie4 hhW W=0:N-2; W=cat(2,W,[N]); k=exp(-i*alpha*W); D=diag(k);
[fKUyIY_ end
!Z5 [QNVaV FF=Ts*HH*D*HH'*2;
W"k8 KODOY % Reference:
a\:VREKj, % by 平先军.一种新的分数阶傅立叶变换快速算法.电子学报.
,i,q!M{- % 2001(3),Vol.29:406-408.
