function??cret=comret（data）
%?以起始日為基點的收益率

ldata=log（data）;
[tn]=size（ldata）;
cret=zeros（t-1n）;
for?i=1:t-1
????cret（i:）=ldata（i+1:）-ldata（1:）;
end

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件????????375??2010-12-16?12:58??dea（new）\bm25（1001）.txt

?????文件????????173??2010-12-16?15:32??dea（new）\comret.m

?????文件????????180??2010-12-29?09:46??dea（new）\crtbi.m

?????文件????????485??2010-12-13?12:49??dea（new）\dea.m

?????文件??????11289??2010-12-29?22:11??dea（new）\deagui.asv

?????文件???????6623??2012-04-17?17:44??dea（new）\deagui.fig

?????文件??????11291??2010-12-29?22:15??dea（new）\deagui.m

?????文件????????582??2010-12-16?10:47??dea（new）\deam.asv

?????文件????????620??2010-12-16?10:54??dea（new）\deam.m

?????文件????????910??2010-12-14?18:43??dea（new）\ga_main.asv

?????文件????????910??2010-12-15?09:21??dea（new）\ga_main.m

?????文件???????1872??2010-06-15?19:00??dea（new）\googleprices.m

?????文件????????264??2010-12-16?17:47??dea（new）\label.asv

?????文件???????3776??2010-12-16?11:31??dea（new）\label.m

?????文件???????1162??2010-12-29?17:31??dea（new）\main.asv

?????文件???????1144??2010-12-29?17:32??dea（new）\main.m

?????文件????????348??2010-12-16?15:09??dea（new）\mvanalysis.asv

?????文件????????398??2010-12-16?15:18??dea（new）\mvanalysis.m

?????文件????????939??2010-12-29?09:58??dea（new）\object.asv

?????文件????????923??2010-12-16?11:00??dea（new）\object.m

?????文件????????907??2010-12-29?10:03??dea（new）\objectnew.m

?????文件????????318??2010-12-16?16:48??dea（new）\plotfc.m

?????文件????????262??2010-12-16?14:12??dea（new）\retdata.m

?????文件????????479??2010-12-20?09:32??dea（new）\returncode.m

?????文件????????513??2010-12-14?15:33??dea（new）\rmna.asv

?????文件????????571??2010-12-14?15:43??dea（new）\rmna.m

?????文件????????442??2010-12-14?13:18??dea（new）\scaleone.asv

?????文件????????471??2010-12-15?10:00??dea（new）\scaleone.m

?????文件???????3760??2010-12-16?11:32??dea（new）\sz180.txt

?????文件??????63488??2010-12-16?13:39??dea（new）\sz2501.xls

............此處省略7個文件信息