README information for j2d

To build jday:

        Load GCC and/or EasyGCC and (if using EasyGCC) drag the project
        folder to the EasyGCC icon. If using GCC at the command line, type
        this: 
        
        gcc c.caldate c.j2d c.version -O2 -o J2D
        
        I have not tested compiling the program with Acorn's Norcroft or
        the APDL's EasyC but there is no reason why it would fail.

To use:

j2d - must have an argument, which is a julian date.
Output will be in the form: year/month/day hour:minute:second

To verify correct operation:  (note: there is a year zero in julian dates)

	jday -4712 1 1 12 0 0
	0.000000      
	   
	j2d 0.0
	-4712/01/01 12:00:00
	
	jday -1 12 31 12 0 0
	1721057.000000   
	
	j2d 1721057.000000
	-1/12/31 12:00:00
	
	j2d 1721058.000000
	0/01/01 12:00:00
	
	jday -d 0/01/01 12:00:00
	1721059.000000  		(why isn't this 1721058 ?)
	
	jday 0 12 31 12 0 0
	1721423.000000   
	
	jday 1 1 1 12 0 0
	1721424.000000   

	jday 1970 1 1 0 0 0
	2440587.500000   
	
	j2d 2440587.500000
	1970/01/01 00:00:00

	j2d 2451774.726007
	2000/08/18 05:25:27
	
	jday -d 2000/08/18 05:25:27
	2451774.726007

As I was checking these dates, I discovered that there is
something unusual going on at JD 1721058
I don't know what that is, but when I compare all these other
date/time checks with the reference in Jean Meeus, Astronomical Algorithms,
first english edition, 1991, they all check out OK, but he doesn't
mention JD 1721058.  Does anyone know what goes on here ?
There might be a bug lurking somewhere here.  This needs to be
checked out more carefully.

	hiram@cruzio.com - 2000/08/18 05:25:27 - 2451774.726007
	Richard Butler   - 2002/04/20 13:12:40 - 2452629.050741