|Re: HP 35s Day of the week program|
Message #4 Posted by Jeff O. on 24 June 2010, 4:30 p.m.,
in response to message #1 by Pablo P (Spain)
Thanks for the program. I think I saw the show about the man who could tell the day of the week for any given date. There was a discussion here a while back about a method to determine on which day of the week the last of February, 7 March, 4 April, 9 May, 6 June, 11 July, 8 August, 5 September, 10 October, 7 November and 12 December will fall in a given year. From there you can quickly figure what day of week any other date will fall. It was called the "doomsday" method, but I preferred to think of it as the "magic day", so that's what I called the program I wrote to calculate it. The meat of the program is the equation below, which was found at the links in message 8 of the discussion.
The year you are interested in must be in stack register x.
Edited: 25 June 2010, 1:17 p.m.