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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Calculating Recurring Work Schedule Off Days in a Given Month [closed]
I have a work schedule that uses a cycle like this:
Day 1: Morning shift
Day 2: Night shift
Day 3: Day off
Day 4: Morning shift
Day 5: Night shift
Days 6-8: 3 days off
Assuming today, May 4th is the ...
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How often would the season cycle be "reset" if the year was 360 days?
I am learning about ancient calendars relating to the sun, and many used a 360 day calendar. If you did that, without adding "5 extra non-days per year" (or 6 on a leap year), then assuming ...
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What is the probability of someone being born both on a Good Friday that is also Friday the 13th
I was born on April the 13th 1990. The day was also Good Friday. I'm wanting to know what the probability/chances of being born on a Good Friday that is also a Black Friday is/are to have an ...
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What is the probability that the fourth business day of the month is Thursday? [duplicate]
This is question 3.16 from the book "Quant Job Interview Questions and Answers" by Mark Joshi et al. The solution given in the book states that for the fourth business day of the month to be ...
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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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1
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Dates on which a day falls, in given month and year.
I was recently given the following problem on a test:
Find the dates on which Sunday fell in July, $1776$.
First, I noted the date on the day of test — $15$ October $2023$ to be a Sunday. Thereafter,...
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Book that goes over mathematics of calendar computations?
What is a good book that goes over mathematics of calendar computations (e.g., calendar systems, date of Easter, etc.)?
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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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Is AD $4000$ a leap year or not?
There is a popular rule to determine which year is a leap year or not.
The year is exactly divisible by four (with no reminder);
If the year is divisible by $100$ (years ending in two zeros), it is ...
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Is Date X + 365 days and Date X + 1 Year always will result in same date?
In particular,
Date X + 12 Months
Date X + 1 Year
Date X + 365 days
Will these result in all same dates at any point of X?
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Is there a way to calculate the exact birthdate of a person based on a series of dates and ages? [closed]
I need to calculate the birthdate of an ancestor based on a list of dates and ages he had, the problem is that I stink at circular maths and rotating stuff.
I have this dictionary in python:
The left ...
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1
answer
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Hash function from date to biweekly event
My trash gets picked up every other Tuesday. Now it's easy to remember what day of the week it is, but not so easy to remember if it's a skip week or not - especially if you miss it sometimes. You ...
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0
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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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How to converts total days passed since epoch from real Gregorian calendar to teorical Gregorian that all years are leap years?
Assuming:
there is a "hypothetical Gregorian calendar" with same notations of the realistic (but no week days);
therefore each date of the hypotetical calendar has the format "month ...
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Calculate what day it will be 100 years [duplicate]
I'm trying to figure out how to calculate the day it will be in 100 years. I've written some python code that takes two inputs from the user, a year and day and then I'm trying to calculate what day ...
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