function?D=fangcha（A）
[mn]=size（A）;
m_a=mean2（A）;%圖像A的平均值
sum_a=0;
for?i=1:m
????for?j=1:n
????????sum_a=sum_a+（A（ij）-m_a）^2;
????end
end
D=sqrt（sum_a/（m*n））;%圖像A的方差

?屬性????????????大小?????日期????時(shí)間???名稱
-----------?---------??----------?-----??----
?????文件?????????187??2013-07-12?16:51??fangcha.m
?????文件????????1062??2016-01-21?15:24??gaopinquyufangchaquda.m
?????文件????????1049??2014-03-28?16:16??gaopinquyunengliangquda.m
?????文件?????????105??2011-06-01?20:21??nengliang.m
?????文件????????1633??2016-01-21?15:25??quyufangchaquda.m
?????文件?????????538??2015-05-29?17:06??quyunengliangquda.m
?????文件?????????834??2016-08-05?17:42??Untitled5.m