Package org.aavso.tools.vstar.util.date

Class MeeusDateUtil

java.lang.Object

org.aavso.tools.vstar.util.date.AbstractDateUtil

org.aavso.tools.vstar.util.date.MeeusDateUtil

public class MeeusDateUtil
extends AbstractDateUtil

This class implements AbstractDateUtil methods using Jean Meeus's Astronomical Algorithms 1991, 1st edition, chapter 7.

Constructor Summary

Constructors

Constructor	Description
MeeusDateUtil()

Method Summary

Modifier and Type	Method	Description
double	calendarToJD(int year, int month, double day)	Method to convert the Julian Day corresponding to the specified year, month, and day.
String	jdToCalendar(double jd)	Method to convert the integer part of a JD into an ISO-8601 calendar date.
YMD	jdToYMD(double jd)	Method to convert the integer part of a JD into a calendar date.

Methods inherited from class org.aavso.tools.vstar.util.date.AbstractDateUtil

getInstance, getMonthName

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

MeeusDateUtil

public MeeusDateUtil()

Method Details

jdToCalendar

public String jdToCalendar(double jd)
                    throws IllegalArgumentException

Method to convert the integer part of a JD into an ISO-8601 calendar date. This method determines the Calendar day given the Julian Day. It is not valid for negative Julian Days (but is valid for negative year results).

Specified by:

jdToCalendar in class AbstractDateUtil

Parameters:

jd - Julian Day (double)

Returns:

calendar date string of the form "YYYY-MM-DD" (ISO-8601 format)

Throws:

IllegalArgumentException

jdToYMD

public YMD jdToYMD(double jd)
            throws IllegalArgumentException

Method to convert the integer part of a JD into a calendar date. This method determines the Calendar day given the Julian Day. It is not valid for negative Julian Days (but is valid for negative year results).

Specified by:

jdToYMD in class AbstractDateUtil

Parameters:

jd - Julian Day (double)

Returns:

structure of the form year, month, day

Throws:

IllegalArgumentException

calendarToJD

public double calendarToJD(int year,
 int month,
 double day)
                    throws IllegalArgumentException

Method to convert the Julian Day corresponding to the specified year, month, and day. The method determines the Julian Day for any year, including dates prior to the start of the Gregorian Calendar. It is not valid for negative Julian Day results (but is valid for negative years).

Specified by:

calendarToJD in class AbstractDateUtil

Parameters:

year - The year.

month - The month (1..12).

day - The day which may contain a fractional component.

Returns:

The Julian Day (double)

Throws:

IllegalArgumentException