General Calendar Functions

Functions
double	ln_get_julian_day (struct ln_date *date)
	Calculate the julian day from date.
void	ln_get_date (double JD, struct ln_date *date)
	Calculate the date from the julian day.
unsigned int	ln_get_day_of_week (struct ln_date *date)
	Calculate day of the week.
double	ln_get_julian_from_sys ()
	Calculate julian day from system time.
void	ln_get_date_from_sys (struct ln_date *date)
	Calculate date from system date.
double	ln_get_julian_from_timet (time_t *in_time)
	Calculate julian day from time_t.
void	ln_get_timet_from_julian (double JD, time_t *in_time)
	Calculate time_t from julian day.
double	ln_get_julian_local_date (struct ln_zonedate *zonedate)
	Calculate Julian day from local date.
int	ln_get_date_from_mpc (struct ln_date *date, char *mpc_date)
	Calculate the local date from the a MPC packed date.
double	ln_get_julian_from_mpc (char *mpc_date)
	Calculate the julian day from the a MPC packed date.

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Function Documentation

void ln_get_date	(	double	JD,
		struct ln_date *	date
	)

Calculate the date from the julian day.

Parameters:

	JD	Julian day
	date	Pointer to new calendar date.

Calculate the date from the Julian day

References ln_date::days, ln_date::hours, ln_date::minutes, ln_date::months, ln_date::seconds, and ln_date::years.

Referenced by ln_date_to_zonedate(), and ln_zonedate_to_date().

int ln_get_date_from_mpc	(	struct ln_date *	date,
		char *	mpc_date
	)

Calculate the local date from the a MPC packed date.

Parameters:

	date	Pointer to new calendar date.
	mpc_date	Pointer to string MPC date

Returns:

0 for valid date

Calculate the local date from the a MPC packed date. See http://cfa-www.harvard.edu/iau/info/PackedDates.html for info.

References ln_date::days, ln_date::hours, ln_date::minutes, ln_date::months, ln_date::seconds, and ln_date::years.

Referenced by ln_get_julian_from_mpc().

void ln_get_date_from_sys

(

struct ln_date *

date

)

Calculate date from system date.

Parameters:

date

Pointer to store date.

Calculate local date from system date.

References ln_date::days, ln_date::hours, ln_date::minutes, ln_date::months, ln_date::seconds, and ln_date::years.

Referenced by ln_get_julian_from_sys().

unsigned int ln_get_day_of_week

(

struct ln_date *

date

)

Calculate day of the week.

Parameters:

date

Date required

Returns:

Day of the week

Calculate the day of the week. Returns 0 = Sunday .. 6 = Saturday

References ln_get_julian_day().

double ln_get_julian_day

(

struct ln_date *

date

)

Calculate the julian day from date.

Parameters:

date

Date required.

Returns:

Julian day

Calculate the julian day from a calendar day. Valid for positive and negative years but not for negative JD.

Examples:

comet.c, and transforms.c.

References ln_date::days, ln_date::hours, ln_date::minutes, ln_date::months, ln_date::seconds, and ln_date::years.

Referenced by ln_date_to_zonedate(), ln_get_day_of_week(), ln_get_julian_from_mpc(), ln_get_julian_from_sys(), ln_get_julian_local_date(), and ln_zonedate_to_date().

double ln_get_julian_from_mpc

(

char *

mpc_date

)

Calculate the julian day from the a MPC packed date.

Parameters:

mpc_date

Pointer to string MPC date

Returns:

Julian day.

Calculate the julian day from the a MPC packed date. See http://cfa-www.harvard.edu/iau/info/PackedDates.html for info.

Examples:

asteroid.c.

References ln_get_date_from_mpc(), and ln_get_julian_day().

double ln_get_julian_from_sys

(

)

Calculate julian day from system time.

Returns:

Julian day (UT)

Calculate the julian day (UT) from the local system time

Examples:

asteroid.c, comet.c, lunar.c, mars.c, and sun.c.

References ln_get_date_from_sys(), and ln_get_julian_day().

double ln_get_julian_from_timet

(

time_t *

in_time

)

Calculate julian day from time_t.

Parameters:

time

The time_t.

Returns:

Julian day.

Calculate Julian day from time_t.

double ln_get_julian_local_date

(

struct ln_zonedate *

zonedate

)

Calculate Julian day from local date.

Parameters:

zonedate

Local date

Returns:

Julian day (UT)

Calculate Julian day (UT) from zone date

References ln_get_julian_day(), and ln_zonedate_to_date().

void ln_get_timet_from_julian	(	double	JD,
		time_t *	in_time
	)

Calculate time_t from julian day.

Parameters:

	JD	Julian day
	in_time	Pointer to store time_t

Calculate time_t from julian day