Questions tagged [calendar-computations]
This tag is for questions about combinatorial and computational issues with regards to calendar systems. A typical, well-known mathematical result in this direction is John Conway's Doomsday Algorithm for computing the "day of the week" associated to a given date.
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Months and notes. Pure coincidence?
There are $12$ months in a year and $12$ notes in the chromatic scale. Moreover, there are $7$ long and $5$ short months and there are $7$ white and $5$ black keys in each octave on the piano ...
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Friday the $13$ths with digits adding up to $13$
Three Friday the $13$ths with digits (in yyyy-mm-dd) adding up to $13$ include 2006-01-13, 2006-10-13, and 2011-05-13.
So, how many such Friday the $13$ths (in the Gregorian calendar) are there from ...
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Why this formula counts passed leap years in Persian arithmetic calendar?
I was reading about a calendar system with these characteristics:
Years are grouped into cycles which begin with four normal years after which every fourth subsequent year in the cycle is a leap ...
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Find the date at which a group of people will reach a target age sum
The goal is to find the date at which the sum of ages of a group of people will reach a certain number.
Though I seem to have found an approximative solution, some issues remains, that I don't know ...
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Lunisolar calendar: what phase was the moon X years ago on the spring equinox?
How would I go around answering these questions (e.g., for $X=10,000$ -- IOW, historical observations are not available and the time is too long ago to rely on a fixed calendar):
How many days ago ...
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Wikitext, #time parser function: Find last month with five Mondays
in Asphalt Wiki, we have templates for repeating events in the Asphalt games. These templates also display if an event is currently running.
In one of the games, events are bound to days of the month ...
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Can an age or a difference between two dates be represented linearly?
I've found an interesting answer on StackOverflow when it comes to calculating someone's age based on that person's date of birth and the date at which the age is calculated. The calculation is ...
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Finding Anchor day of any year using Doomsday rule.
There is a formula or a method given by Sir John Conway to find any given year anchor day after year 1800 assuming that we are using Gregorian calendar .For example for finding anchor day (also known ...
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Determine the busiest day from a list of dates.
There are N date ranges which include check-in date and check-out date. How can I find out the busiest day?
Example:
...
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What adjustments would be necessary to have a remainder of 0 associated with Sunday?
I was reading this below and I had a question:
Link
Take a look under "The Key Value Method" where it says "A remainder of 0 corresponds to Saturday, 1 means sunday, etc."
My ...
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answer
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Why do you subtract 1 in a leap year if the date falls before March?
I was reading this below and I had a question:
Link
Take a look under "The Key Value Method" where it says "If your date is in January or February of a leap year, subtract 1."
I ...
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Question about Gauss' Determination of the first day of the year.
On the wikipedia article
http://en.wikipedia.org/wiki/Determination_of_the_day_of_the_week#Gauss.27_algorithm it explains the Gaussian Formula for calculating the first day of the year. I was ...
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Get number of week by given date and day of week
Is there a formula to get the number of week by a given date and day of week
for example Oct 15, 2014 wed. how do i get what number of week is it?
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Probability of Christmas falling on a particular day of the week
What is the probability that Christmas (on a randomly chosen year) falls on a Monday, Tuesday, Wednesday, &c.? Accounting for the leap years and the 400-year repeating cycle, I wrote a program to ...
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Calculating Calendar Adjustment
I have a data with the Date and Volume column like below, where I am trying to adjust the calendar, the dates are week-ending dates, hence some of the data is missed since May ended with a full week ...
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