date_time.f90 File Reference

(libTheSky version 0.4.3, revision 299, hash 71a3740, 2025-03-02)

Contains date and time procedures for libTheSky. More...

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Modules
module	thesky_datetime
	Date and time procedures.

Functions/Subroutines
subroutine	thesky_datetime::set_date_and_time (year, month, day, hour, minute, second)
	Set global date/time variables (year, month, ..., minute, second in TheSky_local) to specified values.
subroutine	thesky_datetime::get_date_and_time (year, month, day, hour, minute, second)
	Retrieve the current global date/time variables (year, month, ..., minute, second, stored in TheSky_local)
subroutine	thesky_datetime::set_date_and_time_to_system_clock (ut)
	Set global date/time variables (year, month, ..., minute, second in TheSky_local) to system clock.
subroutine	thesky_datetime::ut2lt_ymdhms (year, month, dy, hour, minute, second, tz, tz0, dsttp)
	Convert date/time in ymdhms from UT to local time.
subroutine	thesky_datetime::set_date_and_time_to_jd2000 ()
	Set global date/time variables (year, month, ..., minute, second in TheSky_local) to JD2000.0.
subroutine	thesky_datetime::calctime (ut, jd, jde)
	Compute UT, JD, JDE, DeltaT and TZ, using the date and (local) time and TZ stored in the module TheSky_local.
real(double) function	thesky_datetime::calc_gmst (jd, deltat)
	Calculate Greenwich Mean Sidereal Time for any instant, in radians.
real(double) function	thesky_datetime::gmst_meeus (jd)
	Calculate Greenwich Mean Sidereal Time for any instant, in radians, using Meeus.
subroutine	thesky_datetime::localtime2jd (jd)
	Computes JD, DeltaT and TZ, from date/time variables in module TheSky_local.
real(double) function	thesky_datetime::calc_deltat (jd, force_recompute)
	Compute DeltaT for a given JD.
real(double) function	thesky_datetime::calc_deltat_ymd (y, m, d, force_recompute)
	Compute DeltaT for given y,m,d.
real(double) function	thesky_datetime::find_deltat_in_range (y, y0)
	Find a precise value for DeltaT through linear interpolation of the two adjacent tabulated values.
real(double) function	thesky_datetime::calc_deltat_approx (jd)
	Compute DeltaT for given JD, using a simple parabolic approximation.
subroutine	thesky_datetime::jd2dtm (jd, yy, mm, d, h, m, s)
	Convert a Julian day (UT) to LOCAL date and time (h,m,s)
subroutine	thesky_datetime::jd2dthm (jd, yy, mm, d, h, m)
	Convert a Julian day (UT) to LOCAL date and time (h,m - no seconds)
real(double) function	thesky_datetime::jd2ltime (jd0)
	Convert a Julian day (UT) to a local time (LT, h)
subroutine	thesky_datetime::printdate (jd, jde)
	Prints date/time of a given Julian day (UT) to standard output.
subroutine	thesky_datetime::printdate1 (jd, jde)
	Prints date/time of a given Julian day (UT) to standard output, but without a newline.
subroutine	thesky_datetime::dls (yr, jdb, jde)
	Find the two Julian days of the beginning and the end of daylight-savings time in the EU for a given year.
real(double) function	thesky_datetime::gettz (jd, tz0, dsttp)
	Returns time zone: tz0 (standard time) or tz0+1 (daylight-savings time)
subroutine	thesky_datetime::print_date_time_and_location (op, nlbef, nlaf, ut, jd, jde, locname, tzname)
	Display a banner with date, time and location of calculation. Computes and returns UT, JD and JDE.
integer function	thesky_datetime::dow (jd0)
	Calculates day of week (0 - Sunday, ..., 6=Saturday)
integer function	thesky_datetime::woy (jd)
	Calculate the week-of-year number.
subroutine	thesky_datetime::easter_gauss (year, month, day)
	Calculate the date of Easter using Gauss' method.
subroutine	thesky_datetime::passover_gauss (year, month, day)
	Calculate the date of Passover or Pesach (Jewish Easter) using Gauss' method.

Detailed Description

Contains date and time procedures for libTheSky.

Definition in file date_time.f90.