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Lewis Carroll – computing the day of the week for any given date (1887)

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Re: Lewis Carroll – computing the day of the week for any given date (1887)

#91
post #57

Earlier quoted context omitted.

Like the joke of the guy returning to Boston after being away for years; asks his cab driver "Do you know where I can get scrod" and the driver says "Sure, but I've never heard that in the past perfect before!"

Hmmm. When I heard that joke long ago, the driver said it was the pluperfect subjunctive. And here I took his word for it.

Same thing. From Wikipedia: "The pluperfect (shortening of plusquamperfect), usually called past perfect in English"

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#92

Reading the article, I wandered into the difference of Old Style and New Style dates and what happened in 1752. From [1]: By the 18th century, the English legal year – used for legal, financial and other civil purposes – had for centuries begun on 25 March, or Lady Day.[13][i] Thus, for example, 24 March 1707 was immediately followed by 25 March 1708, while the day following 31 December 1708 was 1 January 1708, with…

The Romans also used the March-based year; that’s why February has fewer days and why October is literally the eighth month

Not just a year starting in March, a year with 10 months -- and 304 days.

It was quite frosty that June and people were hoping for a warm summer come December.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#93
post #72

Earlier quoted context omitted.

> Then Sunday=1, Wednesday=4, etc. That's a helpful encoding because it matches up with numbering that's routinely used in Portuguese, Hebrew, Greek, and by Quakers, among many others. https://en.wikipedia.org/wiki/Names_of_the_days_of_the_week#... These are mostly ultimately because of the Hebrew Bible account in which Sunday is the first day of creation (e.g. Genesis 1:5, 1:8, 1:13, ...).

The numbering itself has little or nothing to do with the Bible. The practice of numbering days of the week is, as the page you linked suggests earlier, widespread and much older than the Bible. Sunday is the day of creation in the Bible because it was the first day in the calendar being used where Genesis was written and translated, so "Day 1" became "Sunday" because to the translator "Sunday" was the first day. Tha…

He didn't ascribe the Biblical narrative to the convention, he mentioned that they match. They could match due to coincidence, due to having a common ancestor, or due to the Biblical narrative itself following the extent (as you claim) standard.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#94

Earlier quoted context omitted.

The numbering itself has little or nothing to do with the Bible. The practice of numbering days of the week is, as the page you linked suggests earlier, widespread and much older than the Bible. Sunday is the day of creation in the Bible because it was the first day in the calendar being used where Genesis was written and translated, so "Day 1" became "Sunday" because to the translator "Sunday" was the first day. Tha…

He didn't ascribe the Biblical narrative to the convention, he mentioned that they match. They could match due to coincidence, due to having a common ancestor, or due to the Biblical narrative itself following the extent (as you claim) standard.

I wrote "mostly ultimately because of", so I did mean to say that I thought the Biblical narrative was the historical reason that most cultures and languages that use this numbering did so.

I'm pretty curious about this question, which I've previously asked in the form of "for how long has there been a worldwide consensus about which day of the week it is?". One answer that I heard is sort of akin to sudosysgen's account, in that some people suggested that the question might not be meaningful: there may have been different cultures with a seven-day week and, when they made sustained contact, instead of debating with each other about "which day of the week it is", they may have understood themselves to be translating their existing names for the weekdays -- some of which were based on numbers.

To the extent that that's a good way of talking about it, I also don't have a good understanding of when those translations would have happened, or who would have made them.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#95
post #81

This is very similar to the method I use and, after conversation with him, the method Art Benjamin uses. It's trivial to do in 10 to 15 seconds, though it requires practice, a very small amount of memorisation[0], and a small amount of mental arithmetic. I use it regularly, partly to keep in practice, and partly because once you have the skill you find it's surprisingly useful. JH Conway used a different technique[1]…

This was the first explanation that I immediately memorised. Thank you for sharing. I got quite a few right, but as I experimented I failed on February 7th 2032. My math was: Years since 2012 is 20 Leap years is 20/4 = 5 Magic month number = 4 Date is 7 (20 + 5 + 4 + 7) % 7 = 1 So I was expecting Sunday, but the answer is Saturday. After some thought I realised: 2032 is a leap year and the chosen date is before Febru…

Exactly so ...

> Leap years is 20/4 = 5

... but because you are in February you have not yet had that leap year, so it's only 4, and then the sums work.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#96
post #27

Earlier quoted context omitted.

If it was phrased 'to which I have swutch' I don't think I'd bat an eyelid! (i.e. past perfect, I think?)

If 'swutch' is the (past) participle of 'to switch': Perfect: "to which I have swutch" Pluperfect/past perfect: "to which I had swutch"

Oh yes, thanks.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#97
post #87

# (jim) C:\Users\Jim>python dow.py # Enter a date (yyyy-mm-dd): 2024-05-24 # The day of the week for 2024-05-24 is Friday. def compute_day_of_week(date): day, month, year = date century = year // 100 year_part = year % 100 # Compute Century-Item if year def day_of_week_string(day_index): days = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"] return days[day_index] # Prompt for the date…

Including 1752 is problematic, in the British Empire, it was the only year with 355 days, as September 3–13 were skipped when the Empire adopted the Gregorian calendar. These skipped days were a rolling problem across the world, when they were applied varied by country and religion of the recorder of historic accounts - they were by no means uniformly applied in the same year across the planet.

I like the story of how the portuguese sailed east, and the spanish sailed west, and by the time they met each other (Macau trading with Manila?) there was a day dislocation between the two empires. Nowadays we have timezones and an International Date Line* to solve the underlying issue, but back then it seems as if no one was surprised that calendars would be off by certain numbers of days between ports, and merely took it in stride.

Lagniappe: https://en.wikipedia.org/wiki/List_of_adoption_dates_of_the_...

* shout out to Kiribati (UTC+14)! I'd like to think the bronze age danes rocked their string skirts in much the same way the Kiribati do their "grass" [pandanus] ones. https://www.youtube.com/watch?v=ZUhs1TdHMt0

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#98
post #27

Earlier quoted context omitted.

If it was phrased 'to which I have swutch' I don't think I'd bat an eyelid! (i.e. past perfect, I think?)

If 'swutch' is the (past) participle of 'to switch': Perfect: "to which I have swutch" Pluperfect/past perfect: "to which I had swutch"

Let's go crazy and do: to whuch I have swutch.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#99

This is very similar to the method I use and, after conversation with him, the method Art Benjamin uses. It's trivial to do in 10 to 15 seconds, though it requires practice, a very small amount of memorisation[0], and a small amount of mental arithmetic. I use it regularly, partly to keep in practice, and partly because once you have the skill you find it's surprisingly useful. JH Conway used a different technique[1]…

I don't quite understand. Your magic month numbers are 3 digits, but you only use one digit in your example. And how does substituting 2012 work, when 2012 was a leap year but 1900 wasn't?

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#100
post #60
post #57

Earlier quoted context omitted.

Like the joke of the guy returning to Boston after being away for years; asks his cab driver "Do you know where I can get scrod" and the driver says "Sure, but I've never heard that in the past perfect before!"

This might be the first time I get a joke's punchline but not the setup

You can create infinite such jokes that end with:

…and the duck said to the bartender, “put it on my bill”

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