HP Articles Forum
[Return to the Index ]
[ Previous | Next ]
Computing Sunrise/Sunset with the HP 35s
Posted by Justin Sloan (Honolulu) on 29 Apr 2013, 12:30 a.m.
This is a port of a program originally written for the HP-67 calculator and published as part of HP's Standard Pac. It can calculate the approximate sunrise and sunset time in GMT given a date and any position on earth in lat/lon. One of the goals of the port was to eliminate the need to use multiple labels, to essentially use branching instead of subroutines. I would love to hear your thoughts or suggestion for improvement.
As an example, to calculate the approximate Sunset on 14 June in Honolulu, Hawai'i, you would press the following keys: 14, STO A, 6, STO B, 21.30, STO C, 157.85, STO D, GTO S001, R/S, 1, R/S.
The answer should be 5.12, meaning 0512hrs (5:12am) GMT. This would be 1912hrs (7:12pm) local HST, since HST is -10 from GMT.
[ Return to the Message Index ]
Go back to the main exhibit hall