double expr_ymd_to_date (double year, double month, double day);
double expr_ymd_to_ofs (double year, double month, double day);
double expr_wkyr_to_date (double wk, double yr);
double expr_yrday_to_date (double yr, double day);
double expr_yrmoda (double year, double month, double day);
double expr_ymd_to_date (double year, double month, double day);
double expr_ymd_to_ofs (double year, double month, double day);
double expr_wkyr_to_date (double wk, double yr);
double expr_yrday_to_date (double yr, double day);
double expr_yrmoda (double year, double month, double day);