HP Forums / HP Calculators (and very old HP Computers) / General Forum v / days-between-dates Solver equation for 17b

Post Reply 
days-between-dates Solver equation for 17b
10-06-2018, 02:06 PM (This post was last modified: 10-07-2018 02:52 PM by Albert Chan.)
Post: #5
Albert Chan Offline
Senior Member
 		Posts: 2,804
Joined: Jul 2018
RE: days-between-dates Solver equation for 17b
Hi, Don Shepherd

Thanks for the DBD algorithm link: https://alcor.concordia.ca/~gpkatch/gdat...rithm.html
Gary Katch also explain why it work: https://alcor.concordia.ca/~gpkatch/gdate-method.html

Based on the explanation, the day number calculation (and its inverse) are only limited by machine precision.

My old day function, using system time, only work for 1970 to 2038.
I coded above in Lua (using IEEE double). Now it can reach 24 trillion years ! Smile
Find all posts by this user
Quote this message in a reply
Post Reply 


Messages In This Thread
RE: days-between-dates Solver equation for 17b - Albert Chan - 10-06-2018 02:06 PM



User(s) browsing this thread: 3 Guest(s)

Contact Us | The Museum of HP Calculators | Return to Top | Return to Content | Lite (Archive) Mode | RSS Syndication