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ISO week date

en.wikipedia.org

61–70 of 91 posts

Re: ISO week date

#61
Dates and times are really screwed up as far as programming goes and there is not much to do about it since that’s the way the earth rotates around the sun and itself. Maybe we should start looking for a planet that has a precise 100 day year without leap years? That year can then be split into 10 weeks. Programming on this planet would be much easier.

Re: ISO week date

#62
As mentioned elsewhere, Intel uses "Work Weeks" for everything. It might be great for manufacturing where a wafer takes a specific number of days to make it through the fab, but it inflicts horrible pain on the folks who have to deal with it and the outside world. My doctor, for instance, stubbornly pretends to not understand when I ask for an appointment in WW04!

December 30th, 2019 is WW01.1 2020 in this calendar. I bet no human in the world knows their WW 2020 birthday.

Re: ISO week date

#63

Earlier quoted context omitted.

> I went metric. That was a mistake. It might be a mistake in the US, but of course machine shops outside the US are all metric - conversely, operating an imperial machine shop might be quite annoying outside the US. > It is fine, I'm happy with my setup. But there are reasons not to pick the "better" method. And those reasons perpetuate the existence of the other ones. Interestingly the US industry didn't switch to…

I live in Canada, we use metric, I had to learn imperial when I started at a machine shop. The machines all worked to .0001 inches and we measured our pieces to 1/16" accuracy. Personally, despite using metric all my life and using it for almost everything else i've done. Using imperial and fractions of inches for that kind of work was more intuitive for me and a lot easier to figure out in my head. I find it a lot e…

> Using imperial and fractions of inches for that kind of work was more intuitive for me and a lot easier to figure out in my head. I find it a lot easier to mentally add fractions than decimals.

Imperial fractions also tend to use base-2 numbers as the denominator. I'd be willing to bet that you infrequently saw anything that used thirds or fifths. Most everything would have been halves, quarters, eighths, sixteenths or even thirtyseconds of something.

Re: ISO week date

#64
post #58

Dates are really hard (I mean data type ones, but ymmv). Numerous libraries claim to be “standard” or to cover almost all date/time functions, but rarely do so. Some libraries allow a developer to see a date as a primitive value/breakdown, which may lead to hard to debug issues (unix + 86400, etc). Leap years, leap seconds, DST, “leapy” UTC/GMT+ days, accidental month overflow, shift date vs duration mismatch, etc. I…

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Re: ISO week date

#65
post #2

ISO week numbers are used a lot in some industries here in Sweden. For example education, so everyone here has encountered them at some point in their lives.

Could this be the one of the reasons ISO week dating was chosen as the format for Minecraft snapshots?

Re: ISO week date

#66
post #5

That is a surprising amount of complexity, really makes you glad that ISO ironed out all the details, so when I recently told our development team composed of Swiss, German, Portuguese and Danish people that we would be going live in week 4 (of 2020), everyone understood just fine. I still find it strange that some countries have not adopted week numbers. Sure, you can say something like "the week of December 21st",…

On the other hand, when I hear "the week of April 9th" I do not have to think a lot about when this is, around which holidays (I am in France :)), the kind of weather we will have, etc.

Week 27 requires some compute to place it somewhere in the year.

Re: ISO week date

#67
post #5

That is a surprising amount of complexity, really makes you glad that ISO ironed out all the details, so when I recently told our development team composed of Swiss, German, Portuguese and Danish people that we would be going live in week 4 (of 2020), everyone understood just fine. I still find it strange that some countries have not adopted week numbers. Sure, you can say something like "the week of December 21st",…

On the other hand, when I hear "the week of April 9th" I do not have to think a lot about when this is, around which holidays (I am in France :)), the kind of weather we will have, etc. Week 27 requires some compute to place it somewhere in the year.

Does the week of April 9th start on a Monday or a Sunday?

If you have a shared context, these kinds of things don’t matter as much. Things get hairy when you don’t, and worse when you think you do, but don’t :)

Re: ISO week date

#68

Earlier quoted context omitted.

Yep, huge companies like Intel use work-weeks for everything. For e.g. planning huge engineering projects was easy: - WW02-WW16: Conceptual Development - WW17: CDR - WW18-46: Detail Design - WW46-48: DDR - WW48-52: Validation/Testing - WW01-02: Ship to customer So you could just now know how many weeks it took exactly for each phase: - [14] WW02-WW16: Conceptual Development - [1] WW17: CDR - [28] WW18-46: Detail Desi…

I appreciate the usefulness of using weeks to measure time. But on a side note: less than 10% of time assigned for validation/testing and at the very end of a project is, in my experience, extremely ambitious.

Lol, please ignore the details, I just quickly wrote it down without thinking to just make a point :) But I agree, its a ridiculous timeline!

Re: ISO week date

#69
post #11
post #9

Earlier quoted context omitted.

I find week numbers very cumbersome to use. Most calendars don't have them by default and most everyday interactions around dates don't involve them. As a result it's a burdensome and unroutined lookup in some arbitrary calendar somewhere just to figure out ballpark distances from current moment. I much prefer date ranges.

Depends a lot on your locale. Physical calendars around here always have them, and all decent calendar software has an option to display them. And if you’d grown up with it, it would be a lot more natural. Much like you probably know what month you’re in without checking your watch, I have a pretty good idea what week we’re in, and if someone says they can deliver something in week 8, I instinctively know that’s late…

I think it's cultural, acquired indeed.

I've pondered on dates and how to divide the year down to how long weeks should be — for way longer than I care to admit.

The thing is, we basically need there characters to map dates (it would be easier with a duodecimal/dozenal system for months, but 1-9,A,B works too).

Using weeks, we could say that e.g. "23-2" is the second day of week 23, from 01-1 to 52-2 (or 52-3 on leap years).

This seems like a good business approach to me.

I'd go one step further and map these to Q's, it's 13 weeks for each (13×4 = 52). Which neatly maps to 12 weeks of work + 1 week transition (debrief, brief) between each Q.

What's interesting is that we count hours, projects, deadlines usually in week units — e.g. most labor regulations speak of weekly work hours, whereas months are sketchy depending where weekends fall, 28-31 days, etc.

So it's easy to think e.g.: we got 3 weeks for this, team of 5, that's 3×5×40 = 600 man-hours.

Finally, considering a 5 workdays week (Mon-Fri), you can easily use .2 increments for days: 24.0 for Monday, 24.2 for Tuesday, 24.4 for Wednesday, 24.6 Thursday and 24.8 Friday of the 24th week. What's the use? Well, between e.g. 24.6 and 28.2 you can quickly do the math and get 4.4 = 4 workweeks + 3 days.

It may seem like nothing but math on dates has always been hard when it doesn't have to be. We shouldn't need Excel or Google to quickly calculate date differences, number of days since/until, etc.

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