function?t3?=?s2_to_t3（s2）;
%?Coherent?matrix?T3
%?Input:?
%???s2:?scattering?matrix?hei?.*?wid?.*?dims（3?or?4）
%?by?Holdlen2DH?2015-03-05?holdlen2dh@gmail.com
[hei?wid?dims]?=?size（s2）;
if?isinteger（s2）
????s2?=?double（s2）;
end
if?dims?==?3
????A?=?s2（::1）?+?s2（::3）;
????B?=?s2（::1）?-?s2（::3）;
????C?=?2?.*?s2（::2）;
elseif?dims?==?4
????A?=?s2（: