%?
%?Author:??Stilian?Stoev?（C）?sstoev@math.bu.edu
%
%?This?function?computes?the?discrete?convolution?of?the?vectors
%?a?and?b?efficiently?by?using?the?FFT?algorithm.
%
%?input:
%??a?<-?a?vector
%??b?<-?a?vector?with?the?same?dimensions?as?a
%??force?<-?if?force?==?1?then?the?FFT‘s?are?“forced“?to?be
%???????????of?dyadic?complexity.
%
%?output:
%??c?<-?the?discrete?convolution?of?a?and?b?that?is
%???????（a（1）*b（1）?a（1）*b（2）+a（2）*b（1）?...）
%?
%?usage:
%???c?=?fftconv（abforce）;
%
%?Written?by?sstoev@math.bu.edu
%
function?c?=?fftconv（abforce）;

na?=?length（a）;
nb?=?length（b）;

if?force
?n?=?2^（fix（log2（na+nb））+1）;
else
?n=na+nb;
end;
A?=?fft（an）;
B?=?fft（bn）;

c?=?ifft（A.*Bn）;
c?=?real（c（1:na+nb-1））;

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件?????????760??2018-04-03?10:36??分形高斯噪聲\fftconv.m
?????文件????????3135??2018-04-02?21:19??分形高斯噪聲\fftfgn.m
?????目錄???????????0??2018-04-03?10:37??分形高斯噪聲\