A good overview on NSRS can be found below, pretty interesting read if you're into datums.
https://www.esri.com/about/newsroom/arcuser/moving-from-stat...
Ending the Era of the U.S. Survey Foot
101–110 of 163 posts
Re: Ending the Era of the U.S. Survey Foot
#102Earlier quoted context omitted.
Yeah, woodworking is so much easier when using feet and inches. It's so incredibly useful to be able to divide a foot into half, thirds, quarters, sixths, and twelfths.
nah, a mm is an incredibly useful unit for woodworking, it's a little less than the width of a saw cut, it's just about the right precision for most woodworking
But a sawcut is (typically) exactly an eighth inch.
Re: Ending the Era of the U.S. Survey Foot
#103Imagine it being 2020 and not using the metric system.
The metric system doesn't really have anything intrinsically better about it. Sure the power of ten thing is convenient, but really that is just sticking to one unit and adding a prefix. You could call "thousandths of an inch" a "milli-inch" and it'd be about the same. Fahrenheit is absolutely a more useful human-scale measurement than Celcius. The boiling point of water is mostly irrelevant to everyday life. At that…
A milli-inch (thou) is actually a commonly used unit in precision manufacturing: https://en.wikipedia.org/wiki/Thousandth_of_an_inch
Re: Ending the Era of the U.S. Survey Foot
#104Thank you 'amjaeger for removing the local-TV-news-level attempted pun from the headline.
Re: Ending the Era of the U.S. Survey Foot
#105I knew about the survey foot because both the l00' tape measures I have are in survey feet. Messed me up on a home construction project about 13 years back. It was then I learned there are 2 differing feet definitions.
Are you sure it was the differing length of each version (about 610 nanometers), or was it because your tapes were marked in tenths of a foot instead of inches?
I have actually worked with people who didn't notice this about their 100' tapes. Even better are the tapes divided by 12 on one side and 10 on the other...
Re: Ending the Era of the U.S. Survey Foot
#106Earlier quoted context omitted.
My wife's family, who almost all have university degrees, who were all born and raised in the US, and who are very familiar with the imperial system NEVER seem to be able to do math with it. They ask me, a European raised with the metric system, for help. Find out how many fl oz of milk are in a measuring cup graduated in units of cups? Ask mrb. Convert my daughter's height from feet/inches to inches? Ask mrb. Conver…
I once worked with a guy who had just bought a surplus cylindrical water tank, and wanted to get an idea of what it would weigh when filled. I asked him for the dimensions and multiplied each by 2.5 to convert to approximately centimeters. Then I multiplied the diameter by 3, approximating pi. I converted each to the nearest power of 2 so I could multiply by adding the exponents. Assuming 1 cubic cm of water is 1 gra…
How would one use the diameter to determine weight? Do we square it then divide by four?
Re: Ending the Era of the U.S. Survey Foot
#107> In 1959, the relationship of the foot to the meter was officially refined as 1 foot = 0.304 8 meter exactly. We can thank one man for this: Carl Edvard Johansson from Sweden. When making gauge blocks, he decided to round off the inch to exactly 25.4mm, and people around the world used his blocks to manufacture everything. The 1959 change just reflected what industry was already doing. - http://mitutoyo.com/wp-conte…
Gauge blocks are quite interesting, particularly how they stick to each other: https://en.wikipedia.org/wiki/Gauge_block#Wringing (mention on HN a few months ago IIRC)
Re: Ending the Era of the U.S. Survey Foot
#108Earlier quoted context omitted.
That's not hard to imagine. Quick, what's 1/3 of a meter? The sometimes problem with metric is it's base-10. The prime factors of 10 are 2 and 5. Feet are in base-12, which has the prime factors 2 and 3. Three is much more useful than five. There are marks on your measuring tape at exactly 1/3 of a yard or 1/3 of a foot. Metric is often easier and more convenient, but not always. So, in the US, we tend to use metric…
My wife's family, who almost all have university degrees, who were all born and raised in the US, and who are very familiar with the imperial system NEVER seem to be able to do math with it. They ask me, a European raised with the metric system, for help. Find out how many fl oz of milk are in a measuring cup graduated in units of cups? Ask mrb. Convert my daughter's height from feet/inches to inches? Ask mrb. Conver…
> Find out how many fl oz of milk are in a measuring cup graduated in units of cups? Ask mrb.
8. Volume is base 2. Two tablespoons in an ounce, 8 ounces in a cup, (there used to be other units in between, but nobody used them, like deci in si) two cups in a pint, two pints in a quart, four quarts in a gallon.
If you were going to sell me on switching units, it would be based on hexadecimal instead of base 10.
> Convert my daughter's height from feet/inches to inches? Ask mrb.
5' is 60". Add and subtract from that. 5'6” is 60"+6" = 66" inches, 4'4" is 60"-8"=52", etc. "Normal" humans cluster around 5' so this takes you pretty far.
> Convert a package's weight from oz to lb/oz? Ask mrb.
Again, base 2. As a programmer this is easy because it leverages all the same neural pathways that I use for converting between base 10 and base 2/16. Hell, maybe learning to cook in base 2 has made me a better programmer.
> Need to know how cold it needs to be outside in farenheit for water to freeze? Ask mrb.
This is definitely the worst example. 0°F is really cold. 100°F is really hot. Fahrenheit is objectively better than Celsius as a common parlance unit.
> I lost count of the number of times they accidentally mix up for example 1.3 feet with 1 ft 3 in.
I've never seen anyone do this ever. I've seen dumb computer systems do shoddy conversions on inputting numbers into a program, but that's why you normalize your inputs and show it back to the user. I've never seen or heard of a living breathing human make this mistake.
> "six pound five"
That's like saying "100 centi 57 meters". Those words have meanings on their own, but they don't have a meaning in that order. The only meaningful response to that is to be confused, and then realize they're confused.
How long did they live in the US and how long have they lived where they are now? This sounds like someone who lived in the US until they were ten and moved somewhere where they not only didn't use customary units but didn't speak English. Then spent the next few years scrambling to master the language and hit adulthood understanding neither US customary units nor metric units.
Honestly, culture, customs, and normality run deep. Those handful of nations that use , as the decimal separator and . as the thousands (or otherwise) separator would have a much easier time and much more benefit swapping their separators than the average American would switching from customary units to SI. Nearly everybody uses a 24 hour day, 60 minute hour, 60 second minute. 3600 second hour, 86400 second day, etc.
Oh did I say 24 hour day? Well I lied but it's close enough.
Astronomers happily use astronomical unit, light-year, parsec, and z= redshift to measure distance all in the same context. For me, having "dumb, arbitrary" units is way less important than having familiar units. Despite the fact that humans are dumb and arbitrary, we're still pretty clever.
Most of the people who complain strongly about customary units, which are dumb and arbitrary, speak languages where inanimate objects have gender. (for the record, I also think grammatical gender is dumb and arbitrary in English) "Auto" (meaning car) is neuter and "Wagen" (meaning car) is masculine. If one considers a scale where 100°F is really hot and 0°F is really cold a dumb, arbitrary system, you should stop to consider whether to_lower(str) and to_lower(to_upper(str)) yield the same results.
Humans are dumb, arbitrary creatures. The fact that US customary units are tend towards base 2 units instead of base 10 is way less arbitrary than daylight savings time, or the fact that France is in the wrong time zone, or the fact that Denmark has enshrined in law its own national time basis and then completely ignores it and then refuses to change the law which is ignored by literally every single person in Denmark.
Re: Ending the Era of the U.S. Survey Foot
#109Earlier quoted context omitted.
Agreed. If you have ever done any type of construction you are very thankful that you can divide a foot evenly by 2, 3, 4 and 6.
Well, architectural construction is based on the "octameter", so 12.5 cm. That adds pretty well ;)
You've flummoxed me with this. The internet seems sure that "octameter" is a "metrical foot", which in this context is quite a pun. Without a link to confirm an architectural connection, I'll take this as a fairly obscure joke...
Re: Ending the Era of the U.S. Survey Foot
#110> In 1959, the relationship of the foot to the meter was officially refined as 1 foot = 0.304 8 meter exactly. We can thank one man for this: Carl Edvard Johansson from Sweden. When making gauge blocks, he decided to round off the inch to exactly 25.4mm, and people around the world used his blocks to manufacture everything. The 1959 change just reflected what industry was already doing. - http://mitutoyo.com/wp-conte…
It frustrates my sense of aesthetics to no end that the inch isn't defined as 25.6 mm. That would make the imperial system a base-two variant of the SI system. This would have made the mile around 42 (current) feet longer, which is a non-starter; I just wish the foot had been a little longer, somehow.
At least you can't blame Johansson for that; 25.6mm would've been so far off (0.8% versus 0.0002%) that people wouldn't have bought his product.
Now I'm wondering how the ratio landed so close to 25.4 in the first place; 25.4000508 and 25.399977 have too many 0s and 9s for random chance.