praytime - produce Islamic prayer time schedule

SYNOPSIS

	  praytime [-h]	[-i] [-f fiqh] [-r ratio] [-a angle] [-t time]
	  [-m time] [ [month] year ]

DESCRIPTION

praytime generates Islamic prayer time schedules and computes the direction of the Qiblah for any location. If no argument is given, the prayer time schedule for the current date at the default location is produced. (The default location is the location specified by appropriately setting the PTLOC environment variable (see below). If PTLOC is not set, the location configured into the program when it was compiled is used.) If a year is specified, the program outputs a schedule for the entire year. If a month is also specified, a schedule just for that month is printed. If the -h option is specified, praytime takes the given month/year as a Hijri month/year (see Hdate/Hcal (1L)) and produces a schedule accordingly.

The year can be between 1900 and 2200, or 0 for a "perpetual" schedule. (Hijri year can be between 1318 and 1625.) The month is a number between 1 and 12. Times in a "perpetual" schedules are essentially the average for the four years of a leap cycle. (The yearly variation in prayer times is seldom more than two minutes, and the times return back to almost the same value every four years.)

praytime allows for Fiqhi variations in computing methods. The following command line options affect the method of computation.

-f fiqh
Fiqh should be S(Hafi'i) or H(anafi). Sets the shadow ratio for determining 'Asr to 1 or 2, respectively. Default value is SHafi'i.
-r ratio
Specifies the value of the 'Asr shadow ratio explicitly. Default value is 1.
-a angle
Specifies Sun's angle of depression at Fajr in degrees. Common values are 18 (for Fajr to be the same as the astronomical twilight) or 15 (a bit later). Default value is 18, which many hold to be the correct value and which is also the value adopted by most Islamic countries today. In North America, the practice has been to use a depression angle of 15. However, in general, extreme care should be employed in this regard and very reliable observational data should be required to accept any value which is less than 18 degrees. The morning twilight marks the beginning of the fasting period in RamaDHaan, and as such, using smaller values for the depression angle may even nullify the Fast.
-m time
Specifies a maximum time interval from Fajr to sunrise in minutes. A common value used is 90 minutes. This method is sometimes used in high- latitude locations where times for the usual values of Sun's depression are undefined or are impractical for certain days during the year.
-t time
Specifies a fixed time interval from Fajr to sunrise in minutes. This value is used to compute daily time for Fajr prayers. A common value used is 90 minutes. This method is sometimes useful in extremely high-latitude locations where times for the usual values of Sun's depression are either undefined or are impractical. Note: 'Isha is computed symmetrically with respect to Fajr, with whichever method is chosen and whatever parameter value is specified. It is an error to specify at the same time both -a and -t or both -t and -m or both -f and -r. To generate schedules for locations other than the location configured into the program, set the PTLOC environment variable appropriately (in your .login file under UNIX or autoexec.bat under DOS) or use the following command line option.
-i
reads name and geographical data for the location from the standard input, instead of using the default location. If standard input is a (terminal) keyboard, praytime prompts the user for the values.

LOCATION DATA

Data supplied through the environment variable PTLOC or via standard input must contain (in given order):

Data items should be separated by whitespace. Input may contain data for more than one location; the tables will be concatenated on the output.

EXAMPLES

The following example produces a prayer time schedule for August 1994.
	       praytime	8 1994
The following command produces a schedule for RamaDhaan 1414.
	       praytime	-h 9 1414
The following command produces a schedule for the year 1994, using the value 15 for the sun's the angle of depression.
	       praytime	-a 15 1994
The following command sequence produces a schedule for the year 1994 for Washington, DC. If need be, set the PTLOC environment variable
		 export PTLOC="Washington, DC  38 54 N	77 2 W	-5 Y"
Then execute:
		 praytime 1994
The following command sequence on produces a perpetual prayer schedule for Washington, DC, using the sun's depression angle of 15 degrees to define Fajr and a shadow ratio of 2 to define 'Asr. The schedule includes adjustment for Daylight Saving Time.

		 cat > dc.dta
		 Washington, DC	 38 54 N  77 2 W  -5 Y
		 ^D
Then execute:
		 praytime -i -a15 -r 2 0 < dc.dta

BUGS

praytime does not correctly handle Daylight Saving Time outside of the United States, As a quick hack, this can be fixed by adding an extra hour to your distance from GMT.

SEE ALSO

hdate/hcal (1L), premind(1L)

AUTHORS

Original program, called `praytimer', produced time schedules in TeX and was derived by Kamal Abdali from his Minaret program for the Macintosh. Waleed Muhanna (wmuhanna@magnus.acs.ohio-state.edu) modified the program to remove all TeX related code; to improve input checking, to allow a default location to be easily configured in; to permit the user to print a schedule for the current date or a specified month and year; and to integrate it with hdate/hcal. Waleed Kadous (waleed@cse.unsw.edu.au) ported the code to the BeOS