Postscript Calendar Program

[David Evans]

I had a quick look through the PostScript code and noticed that the leap year
calculation is wrong - despite being fixed!  Centuries are leap years only
if divisible by 400, not 1000!  The "isleap" procedure should be changed to
the following:

/isleap {		% is this a leap year?
	year 4 mod 0 eq		% multiple of 4
	year 100 mod 0 ne 	% not century
	year 400 mod 0 eq or and       % unless its a century divisible by 400
} def


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|  David R Evans,			   JANET:  dre at cs.nott.ac.uk	      |
|  Electronic Publishing Research Group,   ARPA:   dre%nott.cs at cs.ucl.ac.uk   |
|  Department of Computer Science,	   UUCP:   ... !mcvax!ukc!nott-cs!dre |
|  University of Nottingham,		   Tel.	   NOTTINGHAM(0602) 484848    |
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