FUNCTION daypm, month_i, year_i

@common
@com_eg
;
; define max number of days in month
;
   IF calendar_type LE 1 THEN BEGIN
      IF calendar_type EQ 0 THEN BEGIN
         feb = 28 
      ENDIF ELSE BEGIN
         leap = year_i MOD 4
         IF leap EQ 0 THEN feb = 29 ELSE feb = 28
      ENDELSE 
      CASE month_i OF  
         1: mn = 31
         2: mn = feb
         3: mn = 31
         4: mn = 30
         5: mn = 31
         6: mn = 30
         7: mn = 31
         8: mn = 31 
         9: mn = 30
         10: mn = 31
         11: mn = 30
         12: mn = 31
         ELSE:
      ENDCASE 

   ENDIF ELSE mn = calendar_type

   return, mn
END