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。
i)y8MlC{ uzg(C#sp function FF=frft_PXJ(N,alpha);
V[ju7\>$ Z %matrix
d-c <dS+R % FF is the kernel matrix of fractional Fourier transform
Wip@MGtJ % \copyright: zjliu
? lq % Author's email:
zjliu2001@163.com B|pO2d e Ts=sqrt(2*pi/N); t=-(N-1)/2:(N-1)/2; t=t'; t=t*Ts;
#(swVo:+E variance=N/2/pi; HH=zeros(N); HH(:,1)=1; HH(:,2)=2*t;
%jk7JDvl for k=3:N;
x1H1[0w,i HH(:,k)=HH(:,k-1).*t*2-2*(k-2)*HH(:,k-2);
'yxN1JF end
H3-(.l[!b) HH(:,1)=1/sqrt(sqrt(variance))*HH(:,1).*exp(-t.*t/2);
B-^r0/y; for k=2:N;
_D~l2M HH(:,k)=exp(-t.*t/2).*HH(:,k)/sqrt(2.^(k-1)*...
9<n2-l|) factorial(k-1)*sqrt(variance));
@<kY,ox@~ end
TOapq9B] if mod(N,2)==1;
5. ibH W=0:N-1; k=exp(-i*alpha*W); D=diag(k);
-Zq \x' else
J,4,#2M8 W=0:N-2; W=cat(2,W,[N]); k=exp(-i*alpha*W); D=diag(k);
4>
k"$l/: end
yq. <,b=87 FF=Ts*HH*D*HH'*2;
U\*]cw % Reference:
RO+ jVY~H- % by 平先军.一种新的分数阶傅立叶变换快速算法.电子学报.
! Gob `# r % 2001(3),Vol.29:406-408.
