Metric/imperial

[Kertech]

23 minutes ago, the_pazter said:

yes, that guy needs to learn the history of his own country. English= England, The UK uses Celsius, done, it's over with, I'm off. 

Although a bit of me would more prefer them to use kelvin whenever it's a science situation and provide a Celsius and Fahrenheit (still can't spell that) comparison in brackets

[Tex_NL]

16 hours ago, Camacha said:

This is an argument that has been brought to bear a couple of times now, but has never been substantiated. Please indicate for what applications the imperial system would be more powerful. There does not seem to be a scenario that is not highly trivial. In reverse, there are many examples of how the metric system makes calculations that are complex in imperial a breeze.

The whole concept of the metric system is that it is both powerful and easy. You can traverse the numbers horizontally (quickly changing scale, so going from kilometre to centimetre without making a single calculation). The real beauty, however, is that it also works vertically. If you tell me a pool is 800 centimetre long, 0,006 kilometres wide and 2 metres deep, I can immediately, without a calculator, tell you the respective dimensions in any of those units (8 metres by 6 metres by 2 metres). This also means that calculating the volume is trivial and easily done without a calculator: 96 cubic metres.  Without any additional calculations, I can tell you the pool contains 96.000 litres and filled with water weighs about 96.000 kilos or 96 tonnes.

Try telling me quickly and without pen, paper or calculator what the volume and the weight of the water in a pool 0.003 miles by 20 foot by 120 inches are. As soon as you calculated it in gallons and pounds and someone tells you he needed it in stone and pints, you can whip out the calculator again. We are not talking yet about the fact that there are several standards for ounces, miles and other units.

Imperial seems to work in the select countries it is used, so it certainly is not broken. However, powerful is not a term that springs to mind. It is a system that happened to become whatever it became.

Finally somebody who understands.
A certain distance, volume or weight will always stay the same no matter what yardstick you use and can be calculated to the same accuracy. What matters... the ONLY thing that matters is the ease of conversion from one unit to another.

[sevenperforce]

14 hours ago, AngelLestat said:

Heh, so the imperial system is  powerful if you are using imperial units?    Is like said the Bible is true because the Bible said that is true.

For start, you need to give your result using many units instead one.  

Poor comparison. It's more like you're saying "You only think that it's possible to use the tax code because you're a tax attorney!"

Using many units instead of one is a feature, not a bug, if you're doing mental math. A computer program will be smaller and run faster if it can be written entirely with unsigned int variables rather than float variables, even if it takes a few extra lines of code in certain places. In the same way, humans remember and manipulate single-digit integers more easily than long numbers with lots of decimal points. You probably don't understand this because you don't know how to use Imperial, but having more units makes quantities within the single-digit range of those units much easier to manipulate.

14 hours ago, AngelLestat said:

Is based on SI units (metric).
What you think that E means in metric?  Or C?   C= coulomb? 
All those variables are based on SI.
Energy=joules
M=kilogram
C=speed of light in meters/seconds 
Take a look to formulas in Imperial, they are full of weirds constants that are impossible to remember.

Uhm.

E = mc² is not remotely metric. It is simply an equation. Energy can be represented as joules or as calories or as TNT-tonne equivalents; mass can be represented in kilograms or in grams or in slugs or in Jupiter masses; the speed of light can be provided in meters/second or feet/minute or lightyears/year. It all works.

Sure, metric units are built in such a way as to simplify conversions between different types of things. But that doesn't eliminate weird constants in certain formulas. For example: who wants to deal with 8.3144598 J/mol*K, or 6.67408e-11 m³/kg*s², or 96,485.33289 C/mol?

13 hours ago, kurja said:

I wouldn't divide fractions of cups and spoons at all because I'd be dividing 9dl in half which I can tell without blinking to be 4 and a half dl, it just isn't any more difficult than that. I just find the notion that dividing a number would be any easier if it's followed by a different unit suffix to be silly :/

Well, do you have a 3dl measuring cup and a half-dl measuring cup and a 1dl measuring cup?

The advantage of dividing amounts and ending up with multiple units is it makes actually measuring out those amounts much easier, because you have those units represented physically right in front of you.

13 hours ago, kurja said:

Not really; for different materials you always have to know their density (regardless of unit system), for water it happens to be "1". So you add that one multiplication depending on material. I actually do this on a regular basis at work, it is highly convenient for level measurement by pressure transmitters and such applications.

Which is easy when you're calculating the mass of a 10m*20m*100m swimming pool full of honey, but less so when your dimensions aren't multiples of ten.

10 hours ago, YNM said:

For mass, of course you would divide the number first before massing (weighing) it.

Requiring you to pull out a calculator in all but a handful of cases.

9 hours ago, Kertech said:

sorry....

Been watching this unfold, getting the same arguments, basically Imperial: easier to factorise but a nuissance when doing conversion and science. Metric: good for conversion and scaling but factorising is more difficult. 

Metric allows easier conversion between different types of measurements (volume vs length, energy vs velocity, etc), but since all the units for a given type of measurement are limited to powers of 10, doing mental arithmetic is more challenging unless all your values just arbitrarily happen to be given in multiples of 10.

4 hours ago, Tex_NL said:

A certain distance, volume or weight will always stay the same no matter what yardstick you use and can be calculated to the same accuracy. What matters... the ONLY thing that matters is the ease of conversion from one unit to another.

If you're doing everything with a calculator, sure.

[kurja]

44 minutes ago, sevenperforce said:

Well, do you have a 3dl measuring cup and a half-dl measuring cup and a 1dl measuring cup?

The advantage of dividing amounts and ending up with multiple units is it makes actually measuring out those amounts much easier, because you have those units represented physically right in front of you.

Do you have a separate measuring cup for every 3/8 of a spoon and 9/16 of a cup? Hardly. I have 1dl and 1l measuring cups with scales on the side. If you wanted you could think of l, dl, cl, ml and so on as different units if that makes it easier for you to perceive what kind of quantities they represent.

Which is easy when you're calculating the mass of a 10m*20m*100m swimming pool full of honey, but less so when your dimensions aren't multiples of ten.

No, what the exact dimensions are is irrelevant. Dimensions of containers/vessels are what they are. Calculating 10*10 or 665*174 or whatever with or without a calculator is just as easy or difficult regardless of what units they are. I need to know the volume and height of the vessel and density of the contained liquid, then I can measure the hydrostatic pressure at bottom level and from there it's trivial to give level height and volume and mass of contained liquid. You'd see how and why using metric is an advantage in cases like this if you cared to think of it a little but I see you're more interested in trying to argue. Whatever floats your boat I guess.

[sevenperforce]

37 minutes ago, kurja said:

Do you have a separate measuring cup for every 3/8 of a spoon and 9/16 of a cup? Hardly. I have 1dl and 1l measuring cups with scales on the side. If you wanted you could think of l, dl, cl, ml and so on as different units if that makes it easier for you to perceive what kind of quantities they represent.

Oh, perception isn't the problem; I'm quite familiar with the use of metric. I just also happen to be familiar with the use of Imperial. And so I know the comparative advantages and disadvantages.

Graduated cylinders/measures are fine for most liquids, but they're a pain to use with dry ingredients or viscous liquids. And that's where Imperial has a distinct advantage, because it has a great many units which are all prime factors of each other, on a scale which matches the amounts of those ingredients which humans regularly deal with.

Maybe you can visualize it like this. Suppose you are on a game show, and you need to fill up a series of 10L buckets with varying volumes of sand (to 1 mL precision) in order to trip pressure-sensitive plates and unlock a prize. The sand must be measured using a set of labeled scoops provided by the game; you can take as long as you want, but you need to complete the challenge in as few steps  (each time you dump a scoop of sand is a single step) as possible.

Set A contains a 1 mL scoop, a 10 mL scoop, a 100 mL scoop, and a 1 L scoop.

Set B contains a 1 mL scoop, a 2 mL scoop, a 4 mL scoop, an 8 mL scoop, a 16 mL scoop, a 32 mL scoop, a 64 mL scoop, a 128 mL scoop, a 256 mL scoop, a 512 mL scoop, a 1.024 L scoop, and a 2.048 L scoop.

Which set will you take?

If you're smart, you'll take set B. Sure, the numbers aren't all rounded nicely to multiples of 10...but once you realize that they're all just powers of 2, you can combine them to reach any value between 1 mL and 10 L in a far lower number of steps.

For example, if you need to fill the first bucket to 4.894 L, and chose Set A, you'd have to use 4x1mL + 9x10 mL + 8x100 mL + 4x1 L = 25 scoops. Compare that to 2x2.048 L + 1x512 mL + 1x256 mL + 1x32 mL - 1x2 mL = 6 scoops using Set B. Insisting that metric is always better than Imperial is like choosing Set A because Set B is heavier to carry around.

37 minutes ago, kurja said:

No, what the exact dimensions are is irrelevant. Dimensions of containers/vessels are what they are. Calculating 10*10 or 665*174 or whatever with or without a calculator is just as easy or difficult regardless of what units they are. I need to know the volume and height of the vessel and density of the contained liquid, then I can measure the hydrostatic pressure at bottom level and from there it's trivial to give level height and volume and mass of contained liquid. You'd see how and why using metric is an advantage in cases like this if you cared to think of it a little but I see you're more interested in trying to argue.

Of course metric is more useful in a great many situations. I never denied that.

Edited February 19, 2016 by sevenperforce

[Shpaget]

There is no way I would choose set B in any sane everyday scenario.

If I want efficiency, I would certainly opt to quickly take ten scoops of 1l, rather than to fiddle with various combinations of different scoops.

You are inventing an artificial and unrealistic scenario to give unfair advantage to your arbitrarily chosen scoops.

[kurja]

11 minutes ago, sevenperforce said:

Oh, perception isn't the problem; I'm quite familiar with the use of metric. I just also happen to be familiar with the use of Imperial. And so I know the comparative advantages and disadvantages.

Graduated cylinders/measures are fine for most liquids, but they're a pain to use with dry ingredients or viscous liquids. And that's where Imperial has a distinct advantage, because it has a great many units which are all prime factors of each other, on a scale which matches the amounts of those ingredients which humans regularly deal with.

You know, if it's more of different sized measuring cups that make imperial better(?), there are cups and spoons in kazillion different sizes regardless of what units are labelled on them. I have a set with 5ml, 15ml and lots of different sizes in my kitchen. 

16 minutes ago, sevenperforce said:

Maybe you can visualize it like this. Suppose you are on a game show, and you need to fill up a series of 10L buckets with varying volumes of sand (to 1 mL precision) in order to trip pressure-sensitive plates and unlock a prize. The sand must be measured using a set of labeled scoops provided by the game; you can take as long as you want, but you need to complete the challenge in as few steps  (each time you dump a scoop of sand is a single step) as possible.

Set A contains a 1 mL scoop, a 10 mL scoop, a 100 mL scoop, and a 1L scoop.

Set B contains a 1 mL scoop, a 2 mL scoop, a 4 mL scoop, an 8 mL scoop, a 16 mL scoop, a 32 mL scoop, a 64 mL scoop, a 128 mL scoop, a 256 mL scoop, a 512 mL scoop, a 1.024 L scoop, and a 2.048 L scoop.

Which set will you take?

If you're smart, you'll take set B. Sure, the numbers aren't all rounded nicely to multiples of 10...but once you realize that they're all just powers of 2, you can combine them to reach any value between 1 mL and 10 L in the lowest possible number of steps.

Notice how in both cases the units are metric. If it's the fractions that make your life easier, go right ahead and count in fractions.

22 minutes ago, sevenperforce said:

Of course metric is more useful in a great many situations. I never denied that.

Along the lines of it's more useful as long as everything's in multiples of ten and made of honey, was it?

[sevenperforce]

2 minutes ago, Shpaget said:

There is no way I would choose set B in any sane everyday scenario.

If I want efficiency, I would certainly opt to quickly take ten scoops of 1l, rather than to fiddle with various combinations of different scoops.

You are inventing an artificial and unrealistic scenario to give unfair advantage to your arbitrarily chosen scoops.

Then you would lose. By a huge margin.

There's nothing unrealistic about wanting to reduce the number of steps in a process, and there's nothing arbitrary about using powers of 2.

3 minutes ago, kurja said:

You know, if it's more of different sized measuring cups that make imperial better(?), there are cups and spoons in kazillion different sizes regardless of what units are labelled on them. I have a set with 5ml, 15ml and lots of different sizes in my kitchen. 

Right. Those exist because measuring by factors smaller than 10 is more efficient for a given range of amounts. The advantage of Imperial is that the units themselves exist in a range of prime factors of each other.

5 minutes ago, kurja said:

30 minutes ago, sevenperforce said:

Maybe you can visualize it like this. Suppose you are on a game show, and you need to fill up a series of 10L buckets with varying volumes of sand (to 1 mL precision) in order to trip pressure-sensitive plates and unlock a prize. The sand must be measured using a set of labeled scoops provided by the game; you can take as long as you want, but you need to complete the challenge in as few steps  (each time you dump a scoop of sand is a single step) as possible.

Set A contains a 1 mL scoop, a 10 mL scoop, a 100 mL scoop, and a 1 L scoop.

Set B contains a 1 mL scoop, a 2 mL scoop, a 4 mL scoop, an 8 mL scoop, a 16 mL scoop, a 32 mL scoop, a 64 mL scoop, a 128 mL scoop, a 256 mL scoop, a 512 mL scoop, a 1.024 L scoop, and a 2.048 L scoop.

Which set will you take?

Notice how in both cases the units are metric.

I gave you the units in metric so they'd be more familiar to you, but any arbitrary base unit v works. The point is that measuring by v*2ⁿ or even v*3ⁿ will always offer more flexibility at a given level than measuring by v*10ⁿ.

9 minutes ago, kurja said:

35 minutes ago, sevenperforce said:

Of course metric is more useful in a great many situations. I never denied that.

Along the lines of it's more useful as long as everything's in multiples of ten and made of honey, was it?

No, it's much more useful for converting between different types of stuff, like energy and velocity or mass and density. It's also much more useful when you're jumping wildly between different orders of magnitudes. Doing science is generally easier in metric.

[kurja]

1 minute ago, sevenperforce said:

Right. Those exist because measuring by factors smaller than 10 is more efficient for a given range of amounts. The advantage of Imperial is that the units themselves exist in a range of prime factors of each other.

They exist for convenience, you can measure in whatever factors in any unit system. That there are different unit names for each multiple in imperial is not an advantage.

I gave you the units in metric so they'd be more familiar to you, but any arbitrary base unit v works. The point is that measuring by v*2ⁿ or even v*3ⁿ will always offer more flexibility at a given level than measuring by v*10ⁿ.

Again, there's no need to actually measure anything "in factors of ten" if the units happen to be metric. Count 2ml, 4ml, 8ml if that works for you.

No, it's much more useful for converting between different types of stuff, like energy and velocity or mass and density. It's also much more useful when you're jumping wildly between different orders of magnitudes. Doing science is generally easier in metric.

[Shpaget]

8 hours ago, sevenperforce said:

Then you would lose. By a huge margin.

There's nothing unrealistic about wanting to reduce the number of steps in a process, and there's nothing arbitrary about using powers of 2.

The benefit of using marginally (not hugely) smaller number of steps (8) vs 10, is insignificant compared to ease and practicality of using only one sized container from set A. Set B requires 5 different containers and careful calculation, which introduces multiple opportunities for error. Counting to 10 is significantly easier.

On top of that, again, you are cheating by offering only 4 scoops in set A vs 12 different scoops in set B, among which the largest one is more than double the size of the largest one in set A. If you had played fairly and offered a 2 l scoop in set A (which would be approximate to your 2048 ml in set B), there would be absolutely no contest in whatever aspect of your rigged scenario you want.

[Camacha]

On 19/02/2016 at 5:12 AM, sevenperforce said:

I actually gave a few examples already. In particular, the question was posed of how you'd divide 3 3/4 cups in half; as it turns out, I knew without blinking that that's 2 tablespoons less than 2 cups. 

The Imperial system is more powerful when you're converting between units on the level of measurements around which the Imperial system developed, IF you know how to use it. If you grow up with the metric system, it is hard to understand the advantages of the Imperial system. 
 

Without wanting to sound harsh, but nothing has been shown, other than that the imperial system is workable if you are used to it. Exactly the same conclusion that was reached pages ago. No example has been presented that shows us how the imperial system might be more convenient or more powerful than the system that was specifically designed and, I might add, is continuously updated to be both convenient and powerful.

It is the one thing that is continuously overlooked, and I repeat: the metric system has been designed and then continuously improved to be convenient and easy.

Quote

If you're trying to jump between orders of magnitude, then yes, the metric system's dependence on base 10 is convenient. But if you need to multiply and divide by single-digit integers, having a system with a lot of units that factor into each other by primes is really useful. For example, let's say you're trying to make matching suits for a father and son, and you need to scale down the father's measurements to fit the child. If you are equally well-acquainted with metric and imperial, I guarantee you will find it simpler to scale it down in Imperial.

An example would be in order to show that unmistakable advantage. If it is undeniable, giving a convincing example should be easy.

Of course, that means without picking numbers that exactly happen to fit the imperial standards, because I intentionally avoided doing that with my pool example. We are talking about real life usage here.

 

Quote

The density of water is a bit arbitrary. If it was filled with any other fluid, you're screwed.

The density of water is not arbitrary, since the system was developed and for a time even defined by it. Of course, water is a major factor in our lives, so you both deal a lot and are intuitively acquainted with it. A lot of fluids and matter we deal with in our daily lives are similar enough to make guesstimates easy.

However, dealing with any other fluid is about as easy. The same ease of calculation still applies, only the density changes. Meanwhile, the imperial system always deals with the same kind of conversion and calculations. If I were to get smart with you: by saying you are screwed if it were to be filled with any other fluid (having to know an extra number and doing an extra conversion), you are basically saying you are screwed if you have to do it in metric (knowing lots of extra numbers and doing many conversions).

[Camacha]

11 hours ago, sevenperforce said:

Poor comparison. It's more like you're saying "You only think that it's possible to use the tax code because you're a tax attorney!"

Using many units instead of one is a feature, not a bug, if you're doing mental math. A computer program will be smaller and run faster if it can be written entirely with unsigned int variables rather than float variables, even if it takes a few extra lines of code in certain places. In the same way, humans remember and manipulate single-digit integers more easily than long numbers with lots of decimal points. You probably don't understand this because you don't know how to use Imperial, but having more units makes quantities within the single-digit range of those units much easier to manipulate.

You still seem to miss a fundamental point of the metric system: if you have a number that has many decimal points, then it is easily and without any calculation converted into an integer. It is, in short, the whole point of the system. You have already been shown there are lots of steps to use (even more than people find convenient), so that is not an issue either. Again: the system has been designed for ease and convenience.

Edited February 20, 2016 by Camacha

[PB666]

3 hours ago, Camacha said:

You still seem to miss a fundamental point of the metric system: if you have a number that has many decimal points, then it is easily and without any calculation converted into an integer. It is, in short, the whole point of the system. You have already been shown there are lots of steps to use (even more than people find convenient), so that is not an issue either. Again: the system has been designed for ease and convenience.

a number with many decimal points, all my numbers have one or none?

[Camacha]

1 hour ago, PB666 said:

a number with many decimal points, all my numbers have one or none?

It should have said commas. That is what decent people use.

The phrasing was borrowed from Sevenperforce. File your complaints appropriately.

Edited February 20, 2016 by Camacha

[lajoswinkler]

16 minutes ago, Camacha said:

It should have said commas. That is what decent people use.

The phrasing was borrowed from Sevenperforce. File your complaints appropriately.

I live in a country that deparates its decimals by commas and thousands with points. I cringe every time when I see it.

[Shpaget]

33 minutes ago, lajoswinkler said:

I live in a country that deparates its decimals by commas and thousands with points. I cringe every time when I see it.

Interesting. I've never gotten the impression there is any standard. Throughout my education people used whatever they liked and then change their mind halfway through writing the number.

[AngelLestat]

57 minutes ago, lajoswinkler said:

I live in a country that deparates its decimals by commas and thousands with points. I cringe every time when I see it.

Why?  it has more sense than the other way from my perspective.
Because a "," is more notorious than a "."
The same for the long and short scale with "billions and trillions", our way has more sense from the math point of view and name.
I can continue with the date:  month-day-year..    what is the sense of that?
Almost no US standard has common sense.

[Camacha]

59 minutes ago, Shpaget said:

Interesting. I've never gotten the impression there is any standard. Throughout my education people used whatever they liked and then change their mind halfway through writing the number.

People use different standards in different areas of the world, but I am pretty sure most frown upon not being consistent. The meaning actually changes, so if you use both at random, accidents are bound to happen sooner or later. Find out more here.

Edited February 20, 2016 by Camacha

[lajoswinkler]

1 hour ago, Shpaget said:

Interesting. I've never gotten the impression there is any standard. Throughout my education people used whatever they liked and then change their mind halfway through writing the number.

Neither have I until a few years ago when I realized banking had it very strict, adhering to the national standard.

I could survive with commas used for decimal marks (surive, but cringe), but to use points to separate thousands? Why not simply spaces? It's ugly, confusing and could cause a major mistake to be made if the number contains no decimals. For example, one thousand fifteen would be 1.015 which could be interpreted as one point zero fifteen.

 

58 minutes ago, AngelLestat said:

Why?  it has more sense than the other way from my perspective.
Because a "," is more notorious than a "."
The same for the long and short scale with "billions and trillions", our way has more sense from the math point of view and name.
I can continue with the date:  month-day-year..    what is the sense of that?
Almost no US standard has common sense.

Most of standards USA uses is totally screwed up (imperial system as a tumor on SI, month-day-year, electrical standards which cause higher metal consumption, etc.), but I must say that "millions and billions" have more sense than "millions and milliards, billions and billiards". Also the usage of point for decimal mark, I like that a lot.

Edited February 20, 2016 by lajoswinkler

[kunok]

1 hour ago, lajoswinkler said:

I must say that "millions and billions" have more sense than "millions and milliards, billions and billiards".

Here nobody uses milliards, I only see it used in weird translations from the English (hey at least it's better than when they translate bad as billion), we use million and "miles de millones" thousands of millions , a billion is a million of millions, a trillion a million of million of million, it's pretty coherent, it's based on a million step. It doesn't seem to have sense to me that a thousand step based unit starts with million and not in thousand.

[Camacha]

2 hours ago, lajoswinkler said:

Why not simply spaces? It's ugly, confusing and could cause a major mistake to be made if the number contains no decimals. For example, one thousand fifteen would be 1.015 which could be interpreted as one point zero fifteen.

Separating numbers with points increases legibility and actually prevents error. It is just that some people decided to invent their own standard that confuses things Spaces could cause issues, as there is no way to distinguish a couple of numbers from one big number. 256 896 987 might be 256, 896 and 987, or it might be 256.896.987. There is a reason IP addresses do something similar It is a pretty trivial issue, however.

Honestly though, both work pretty well, and are easy to get used to. Both being used at he same time without a proper indication before hand is what complicates things. It would be easier if one or the other would be used exclusively.

Edited February 20, 2016 by Camacha

[lajoswinkler]

1 hour ago, Camacha said:

Separating numbers with points increases legibility and actually prevents error. It is just that some people decided to invent their own standard that confuses things Spaces could cause issues, as there is no way to distinguish a couple of numbers from one big number. 256 896 987 might be 256, 896 and 987, or it might be 256.896.987. There is a reason IP addresses do something similar It is a pretty trivial issue, however.

Honestly though, both work pretty well, and are easy to get used to. Both being used at he same time without a proper indication before hand is what complicates things. It would be easier if one or the other would be used exclusively.

Of course. I vote points for decimal marks, commas for thousands.

[YNM]

Other way around down here... We even say them "koma" (comma) when start talking numbers below 1 but above 0.

[Bill Phil]

Commas are bigger than decimals, and if you use them to separate every 3 powers of ten, it's a bit easier than decimals. Also, why every 3?

[Bill Phil]

16 hours ago, AngelLestat said:

Why?  it has more sense than the other way from my perspective.
Because a "," is more notorious than a "."
The same for the long and short scale with "billions and trillions", our way has more sense from the math point of view and name.
I can continue with the date:  month-day-year..    what is the sense of that?
Almost no US standard has common sense.

The month date year thing makes a lot of sense. Here, people like to know about the month of the year more than the day, probably because of sports seasons, or something like that. The day comes second, since it's not all that important, and the year last, since you should know the current year.

It also has to do with saying "Month Day", like June 12th. It's the order people are used to. It's also a bit faster than 12th of June