function?imf?=?emd（x）??????????????????????????%EMD的實(shí)現(xiàn)函數(shù)
%?Empiricial?Mode?Decomposition?（Hilbert-Huang?Transform）
%?imf?=?emd（x）
%?Func?:?findpeaks

x???=?transpose（x（:））;
imf?=?[];
while?~ismonotonic（x）
???x1?=?x;
???sd?=?Inf;
???while?（sd?>?0.1）?|?~isimf（x1）
??????s1?=?getspline（x1）;????????????????????????%s1是極大值包絡(luò)
??????s2?=?-getspline（-x1）;??????????????????????%s2是極小值包絡(luò)
??????x2?=?x1-（s1+s2）/2;?????????????????????????%x2是原信號(hào)減去極大值包絡(luò)和極小值包絡(luò)之和的平均值之后的剩余部分
??????
??????sd?=?sum（（x1-x2）.^2）/sum（x1.^2）;???????????%極大值與極小值包絡(luò)平均值的平方和與原信號(hào)的平方和之比小于0.1，則認(rèn)為滿足IMF的第二個(gè)條件。
??????x1?=?x2;
???end
???
???imf{end+1}?=?x1;???????????????????????????????%x1是個(gè)向量
???x??????????=?x-x1;
end
imf{end+1}?=?x;

%?FUNCTIONS

function?u?=?ismonotonic（x）???????????????????????????????????????%判斷X是否是單一分量

u1?=?length（findpeaks（x））*length（findpeaks（-x））;
if?u1?>?0?u?=?0;
else??????u?=?1;?end

function?u?=?isimf（x）?????????????????????????????????????????????%判斷X是否是IMF分量

N??=?length（x）;
u1?=?sum（x（1:N-1）.*x（2:N）?u2?=?length（findpeaks（x））+length（findpeaks（-x））;??????????????????%極大值與極小值總數(shù)
if?abs（u1-u2）?>?1?u?=?0;?????????????????????????????????????????%極值點(diǎn)數(shù)與零點(diǎn)數(shù)相等或相差一個(gè)時(shí)，為IMF分量
else??????????????u?=?1;?end?????????????????????????????????????%findpeaks（x）得到極大值點(diǎn)，findpeaks（-x）得到極小值點(diǎn)

function?s?=?getspline（x）?????????????????????????????????????????%三次樣條插值得到極大值點(diǎn)的包絡(luò)

N?=?length（x）;
p?=?findpeaks（x）;
s?=?spline（[0?p?N+1][0?x（p）?0]1:N）;

?屬性????????????大小?????日期????時(shí)間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2018-03-30?10:35??EMD-Hermite\
?????文件????????1690??2011-02-28?16:17??EMD-Hermite\emd.m
?????文件????????1424??2011-03-01?09:37??EMD-Hermite\EMD_Hermite.m
?????文件????????3406??2011-03-01?16:07??EMD-Hermite\EMD_Hermite_tst.asv
?????文件????????3406??2011-03-10?15:20??EMD-Hermite\EMD_Hermite_tst.m
?????文件????????3865??2011-03-01?14:41??EMD-Hermite\EMD_Hermite_tst_1.m
?????文件????????3409??2011-03-01?16:13??EMD-Hermite\EMD_Spline_tst.m
?????文件?????????382??2011-03-01?11:29??EMD-Hermite\point.m
?????文件?????????652??2011-02-25?10:36??EMD-Hermite\subHermite.m
?????文件????????1240??2011-03-01?11:15??EMD-Hermite\subHermite_test.asv
?????文件????????1234??2011-03-01?11:22??EMD-Hermite\subHermite_test.m
?????文件?????????468??2011-02-28?15:05??EMD-Hermite\tst.m
?????文件???????66732??2011-03-01?16:07??EMD-Hermite\untitled.emf