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。
uA\J0"0; } H06Bj(Y! function FF=frft_PXJ(N,alpha);
A}G|Yfn %matrix
(
v@jc8y % FF is the kernel matrix of fractional Fourier transform
>&Fa(o;* % \copyright: zjliu
rkYjq4Z@ % Author's email:
zjliu2001@163.com B*@6xS[IL Ts=sqrt(2*pi/N); t=-(N-1)/2:(N-1)/2; t=t'; t=t*Ts;
|Td5l? variance=N/2/pi; HH=zeros(N); HH(:,1)=1; HH(:,2)=2*t;
inF6M8
A1 for k=3:N;
O3%[dR HH(:,k)=HH(:,k-1).*t*2-2*(k-2)*HH(:,k-2);
&U &%ka<* end
@G G ccF HH(:,1)=1/sqrt(sqrt(variance))*HH(:,1).*exp(-t.*t/2);
Y\? j0X; for k=2:N;
_e 'Y3:
HH(:,k)=exp(-t.*t/2).*HH(:,k)/sqrt(2.^(k-1)*...
^l !L)iw factorial(k-1)*sqrt(variance));
\0AiCMX[ end
{L0;{ if mod(N,2)==1;
G|9B )`S W=0:N-1; k=exp(-i*alpha*W); D=diag(k);
a$}mWPp+f else
_P 5P(^/ W=0:N-2; W=cat(2,W,[N]); k=exp(-i*alpha*W); D=diag(k);
2k1 aX~? end
.nZ3kT` FF=Ts*HH*D*HH'*2;
vWY (% Q, % Reference:
tWD|qg_ % by 平先军.一种新的分数阶傅立叶变换快速算法.电子学报.
g%\L&}Jd % 2001(3),Vol.29:406-408.
