Matlab年积日换算为日期代码

function [md] =fun_date（ydays）
% NOTES:
% - This function was originally produced by Ming Shen.
%
    % 本函数将年积日转换为正常日期
    if days        m=1;
        d=days;
    else if days        m=2;
        d=days-fun_AnnualDay（ y21）+1;
         else if days                 m=3;
                 d=days-fun_AnnualDay（ y31）+1;
             else if days                     m=4;
                     d=days-fun_AnnualDay（ y41）+1;
                 else if days                      m=5;
                      d=days-fun_AnnualDay（ y51）+1;
                     else if days                             m=6;
                             d=days-fun_AnnualDay（ y61）+1;
                         else if days                                 m=7;
                                 d=days-fun_AnnualDay（ y71）+1;
                             else if days                                     m=8;
                                     d=days-fun_AnnualDay（ y81）+1;
                                 else if days                                         m=9;