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Show HN: Weekle – a web app to learn how to calculate the day of the week

benjoffe.com

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Show HN: Weekle – a web app to learn how to calculate the day of the week

#1

Post by benjoffe »

Mentally calculating the day-of-the-week for any date in history sounds like an impossible task for a normal person, but the algorithm is actually pretty simple to learn.

Although there are tutorials for this elsewhere online, and little quizzes available, there didn't seem to be anything well optimised with multiple practice modes etc.

I originally created a basic version of this just for myself, but a small group of friends and family found it interesting and gave suggestions such as the daily game.

Multi-lingual support is a bit rudimentary at the moment, it will only translate the month names and weekday names, not other text. If any translation mistakes are identified please let me know.

Other feedback is welcome too.

Show HN: Weekle – a web app to learn how to calculate the day of the week
benjoffe.com

Re: Show HN: Weekle – a web app to learn how to calculate the day of the week

#3

Post by midasuni »

First question was “08/10/2023”

The majority of the world uses little endian, so the 8th day of the 10th month of the 2023rd year. 8th October is Sunday, as I know that because it’s the same day as 9th of May.

However experiments E has told me that much of the internet uses the minority American view of “middle endian”

Probably worth making it clear.

Re: Show HN: Weekle – a web app to learn how to calculate the day of the week

#4

Post by naniwaduni »

midasuni wrote: post #3

First question was “08/10/2023” The majority of the world uses little endian, so the 8th day of the 10th month of the 2023rd year. 8th October is Sunday, as I know that because it’s the same day as 9th of May. However experiments E has told me that much of the internet uses the minority American view of “middle endian” Probably worth making it clear.

Big-endian numerals in little-endian component order is still ixUn-endian! YMD or little-endian numerals, then we can talk :p

Re: Show HN: Weekle – a web app to learn how to calculate the day of the week

#6

Post by benjoffe »

entropy47 wrote: post #5

Can you add more detail on the year table at the very bottom / how you're meant to use it? I can memorise it but I'm not sure how you're meant to use it after that.

Thanks, that's a good point that it does not clearly explain the use of that table. I will update the page soon to explain that the table cell represents the last 2 digits of a year, and the left column is the result of the year calculation for that year. The table has only 28 years in it since any year 28 or higher can be simplified by subtracting 28, 56 or 84.

I recommend only attempting to memorise the table after you are already able to calculate the year number using the normal algorithm.

Re: Show HN: Weekle – a web app to learn how to calculate the day of the week

#8

Post by Retr0id »

connordoner wrote: post #2

I love the bit that sticks out on desktop with the QR code. Stellar work, Ben!

That's funny, I actually came here to complain about that. I find it visually distracting and there was no obvious way to dismiss it, so I had to use a content blocker.

Re: Show HN: Weekle – a web app to learn how to calculate the day of the week

#10

Post by rahimnathwani »

robobro wrote: post #9
scotteh wrote: post #7

This looks easier to memorise than another method: https://en.wikipedia.org/wiki/Doomsday_rule Nice work on the site!

How is it easier? I can do Doomsday in about 5 seconds for any year AD 1800 - 2200

I don't think I'll spend the time to memorize the part for the anchor days, but the observation that March 0, 4/4, 6/6, 8/8, 10/10, 12/12 all land on the same day will definitely come in handy.
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