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。
><D2o f| $;G<!]& s function FF=frft_PXJ(N,alpha);
TMY. z
%matrix
XXn3K BIf % FF is the kernel matrix of fractional Fourier transform
/eH37H % \copyright: zjliu
H M0 & % % Author's email:
zjliu2001@163.com }(!Uq Ts=sqrt(2*pi/N); t=-(N-1)/2:(N-1)/2; t=t'; t=t*Ts;
(|Gwg \r variance=N/2/pi; HH=zeros(N); HH(:,1)=1; HH(:,2)=2*t;
u9KT_`
) for k=3:N;
iYvzZ7
8f HH(:,k)=HH(:,k-1).*t*2-2*(k-2)*HH(:,k-2);
,M?8s2? end
-O ?Hf Q HH(:,1)=1/sqrt(sqrt(variance))*HH(:,1).*exp(-t.*t/2);
Qx,#Hj for k=2:N;
|[iO./ zP HH(:,k)=exp(-t.*t/2).*HH(:,k)/sqrt(2.^(k-1)*...
;@ixrj0u factorial(k-1)*sqrt(variance));
#GlFm?/6K/ end
}=R0AKz!Cv if mod(N,2)==1;
R/"-r^j W=0:N-1; k=exp(-i*alpha*W); D=diag(k);
S-o )d else
"1^tVw| W=0:N-2; W=cat(2,W,[N]); k=exp(-i*alpha*W); D=diag(k);
y[.lfW?) end
.rO~a.kG FF=Ts*HH*D*HH'*2;
"Hz%0zP& % Reference:
)#i"hnYpQ % by 平先军.一种新的分数阶傅立叶变换快速算法.电子学报.
yH-&o, % 2001(3),Vol.29:406-408.
