%---------------------------------------------------------------------------------------------
%?PROGRAM:?LGModes
%?AUTHOR:??Shaowen?Xuan
%?DATE:????12/26/15
%
%?INPUT?ARGUMENTS:
%?----------------
%?mmatnmat???=?Laguerre?Gaussian?mode?matrix?（or?matrix?generate?by?meshgrid）
%?umat????????=?coefficients?for?each?mode
%?w???????????=?the?beam?effective?radius
%?r???????????=?radial?position?vector?（or?matrix?generated?by?meshgrid）
%?theta???????=?azimuthal?position?vector?（or?matrix?generated?by?meshgrid）
%
%?OUTPUT?ARGUMENTS:
%?----------------
%?z?????=?the?superposition?of?LG?modes
%---------------------------------------------------------------------------------------------
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