function?y=myfft（x）
%x?is?the?input?sequence
%n?is?the?point?of?fft
M=nextpow2（length（x））;%Series?of?Butterfly?operation
N=2^M;
for?m=0:N/2-1%range?of?Rotating?factor?index?
????WN（m+1）=exp（-1i*2*pi/N）^m;%Compute?Rotating?factor
end
A=[xzeros（1N-length（x））];
%The?operation?of?reverse?order?data
J=0;%inversition?of?Decimal?number
for?I=0:N-1
????if?I????????T=A（I+1）;
????????A（I+1）=A（J+1）;
????????A（J+1）=T;
????end
%Calculate?an?next?inv