Are "On LINE" calculators useful to you??

I just looked at the thread - not hard to find. I'd make a couple of points;

If some youngster or (anyone) was trying to be helpful that's fine.

Said person got an undeserved bashing.

Nobody commented on useful links within said calculator.

Nobody commented that calculator link may have been established to create advertising revenue.

I am suspicious of the posters intent , but see no reason to be unkind. It may have been a just as it appears - an innocent first post by someone wanting to be helpful. I think some of those responding got a bit carried away and probably regret the first impression they may have given. I would have pointed out the lack of need for the calculator and asked the poster if they had financial motive. This would have been preceded by 'welcome' and ended with some light -hearted joke.

Hi Kris --

I will take that as a no vote thanks for your comments. I'm really curious about the number of folks who do or do not use them. I have used them but rarely. Mainly for material weight and conversions for the weights to metric. The formulae always escapes me.

Rich

Hi Rich

Personally I'd not have need for the calculator offered , but I see no harm in anyone posting such a thing - CR4 should not be too snooty in what level of knowledge people have. I've seen some great threads on elementary things , and they will all find a grateful user somewhere.

I think the poster was unfortunate - too many people in the wrong mood at the wrong time (hardly fair to pick on a new member). With that said , I am a litttle suspicious of motive. Hopefully it will all pass.

Kris

I use them all the time - I have several bookmarked.

To paraphrase Einstein, "Why should I clutter up my head with formulas I can get in two clicks of a mouse?"

Online calculators are very useful! Why would they not be?

I use online conversion calculators occasionally and think they can be very useful, especially when one needs to convert some arcane units.

I like an intelligent inline calculator.

By inline I mean it is part of the input field on a database.

If the field are selected as mm it must be capable of accepting any input in any length unit. For example if you enter 2" in the field it must convert it to 50.8 mm and save it that way.

The unit I have used it the most was for area conversion.

The diagram area in the units used at that time can be entered and will be converted to ha.

Examples of entries 123a 3r 12p - 12.3m - 12m 218r -

Calculations can also be done : 123a - 12.3a - 1893f

a=acres R rudes p=perches f=ft2 m=morgen

Another favorite is the x,y to latitude ,longitude or lat,long to x,y or Lo to Lo etc

using 3 fields for saving

A complex online calculator is ok.

I find a few on line calculators to be very useful, and I rely on them regularly. Many are of no use to me but may be helpful to others. Some of them are truly junk, a sub group of these are intended to get you to buy something.

of course they are

Yes, definitely very useful. Beats memorizing scores of formulae for converting this unit to that unit ad infinitum.

Thanks to everyone for your responses. From what I have read so far regarding the question. It is just short of unanimous that the folks on on CR4 (so far) do think they are useful.

I believe (so far) that the following statement is inaccurate, and the trend will probably continue in this direction.

"And, hey, if you find this "tool" useful, that's great. Just don't be surprised if you find that most here on this forum do not consider it so". Is This A True Statement??

In case I wasn't clear , om-line calculators are useful. I read that as unanimous.

(I expressed reservation cos I tracked down what you were referring to)

Sorry Kris -- I misread you. Thanks.

Yes, So far there is a unanimous response.

No problem - maybe you can spread the word . I'd say 100% support wins a case.

I'm very tempted to reference this in that other thread - but I think I will let that discussion die out on it's own. Maybe the folks who made the unsubstantiated claim about CR4 folks not using on-line calcs will stumble onto this by chance. Still tempting though.

Thanks - Rich

Hi again Kris, I gave in to temptation and posted these results in the other thread, Useful tool when designing an antenna . Couldn't resist, as I am curious about what type of response will be made. Pretty predictable -- maybe.

I know that these responses only represent a small population on CR4 but "IMHO" I think they might be a good indicator of a trend that would hold true throughout the forums.

New Avatar? Nice.

Good move cross-linking , I was hoping you would.

<'nutkin' has been around for some time , he alternates with my other devilish persona. Changes between the two are without meaning. Most people seem to prefer nutkin for some reason. >

Hmmmm ... online calculators need to be trustworthy, because the people who use them may assume them to be. If the calculator is not trustworthy, grief can result, possibly some liability, too!

A certain stainless steel association has a simple list of properties arrayed by grade of steel, up on its website. Some of them are plain wrong. Electrical resisitivity is one of those values they mis-represent.

When I demonstrated the error through their feedback form, nobody responded, nothing has changed on their website, two years on. Imagine the havoc if I had relied on their values, let alone relied on a calculator with the values embedded. People or groups who represent themselves as authoritative should expect they will be relied upon and should behave more responsibly than this stainless steel industry association.

So at the very minimum, I would expect an online calculator to be expertly tested, perhaps with the expert certifying it professionally, involving his reputation and his liability. Is this going to happen for a freebie calculator?

The company where I work has one online calculator at its website, for some nasty trigonometry used in tilt-tool rotary milling, which was not released until the Chief Technical Officer tested it to exhaustion. His reputation is on the line and he took responsibility. I suspect that will be pretty rare!


The calculator concerned is CORRECT and for the record is found at
http://www.fourth-axis.com/ireocalc/

Chris Cheer
Fourth Axis

If you want to do big precision numbers I wouldn't trust Excel too far. It ain't up to much.

Hi Guest - You make a very good point and, as with anything used for serious business it should be checked. But so should all calculations be verified (double checked) regardless of the means the result was achieved. Kinda like the old saying "Measure Twice - Cut Once" If something is a critical requirement for material used, I would order a vendor certification for my materials and verify the critical properties upon receipt.

I don't use them, and rarely do I use pre-setup spreadsheets. Just something requires me to know what's going on behind the curtain. Once I know what's going on behind the curtain, me and my trusty TI-85 or spreadsheet can figure it out just as quick.

My >opinion<, they're a waste of server space and as already mentioned are usually full of ads. But that's just my opinion. For those who find them helpful, they probably aren't a waste of space.

There are many great online calculators, of all sorts. One of my favorite, which I use frequently (partly just for fun) is the one that is built into Google. Just type any calculation into the search line, and it usually recognizes it as a calculation, and does the math. Google "knows" the value of many physical constants (G, Planck's, Stefan-Boltzmann, proton mass, mass of all the planets (and Pluto) ...) and is perfectly happy with mixed units, and will provide the answer in whatever units you choose.

Type "4 amps x 2 volts in HP" hit enter, and you get 0.0107281767 HP.

Type "2 furlongs x 4 fathoms" and you get 2943.16831 m^2

I can't tell you how many times I've worked with computer engineers from Rome who use roman numerals (of course)! So I just type in "CLXVII in hexadecimal" and up pops CLXVII = 0xA7.

If you have Google toolbar, the calculation is done before you hit enter.

Fun to play with, and often useful. If I were doing any calculation I have to rely upon, I'd rather put it in a spreadsheet, so I can ponder it a bit. But for something quick, and where I have already estimated the answer, Google is great.

I didn't know it could handle Roman numerals. That's fun. It sure makes Roman maths easier.Lack of place value - doh. Have you idiot tested it Ken ? (ie for different conventions of showing numerals - I am extremely lazy !).Oops , that sound's rude -no inference intended . Perhaps I'll test it myself then. Presumably Google calculator has a 'favoured' format , I just wonder if it is possible to confuse it.It's also set me wondering on the mischief I could cause by using roman numerals all over the place. he he.

I think Wiki may need to update that pic of the cutty sarc !

Some of the free calculators are pretty useful - often on manufacturers' sites* and university ones. But I wouldn't rely on them unless I know something about the provenance. Even those without provenance can be useful to check calculators that I have built for myself (against syntax and other "obvious" errors).

Fyz

*A good calculator on the right topic can both reduce the number of calls to a manufacturer's help-line, and bring in business from users who have found them useful, so they are can be worthwhile investments.

ms keep pretty quiet about some of their stuffs limitations. If a column is set up in Excel to do something like 2ⁿ , then the curtailing of digits shows up soon enough*. Probably no big deal in most peoples lives , but I think it's certain someone somewhere will have been left scratching their head.

* It would have you believe that zero's start appearing at the end instead of 2,4,8,6,2,4,8,6....

MS spreadsheet was originally designed as a clone of Lotus. It was pretty-much identical in every non-copyright aspect.

Calculations are actually made using IEEE standard double precision arithmetic (52-bit precision), which is about one digit more than are displayed - so this is some sort of attempt to indicate the limits. Unfortunately, if you take small differences, the system can display spurious accuracy, so they haven't gone as far down the route of protecting the user as you might wish.

If I'm worried about greater precision, I use a 36-digit calculator if the calculations are simple; otherwise, I write a programme...

N.B. that most systems use IEEE double precision arithmetic, and many do not even provide this level of warning - so you could find yourself making calculations of similar dubiosity (sic) without being aware of it.

BTW, the open office calculator uses the same nominal precision, but sometimes gives different results beyond that...

Fyz

Hi Fyz,

I stumbled ( here's a good choice of phrase) across the ms flaw when doing something I've since forgotten. I used my naff Qbasic to write a quick routine for multiplying larger numbers. It just loops around a couple of arrays and seems to do the job fine. I think the array size in my QuaintBasic is limited at 64k which is enough to tweak a couple of numbers to make it go as far as I'd ever want it to go (I think I last had it at 40 x40 digits). Some day I'll put a few bells on the thing and make it do more things. I like the simplicity of Qbasic - it has quite a cult following on the web.

It's amazing how many different calculators (for all sorts of strange things ) exist out there.

kris

I think you are probably looking at the integer function in Qbasic, rather than precision of floating point numbers. I rarely (if ever) need large integers to be precise, so this wouldn't help me a lot.

But I expect that, like most programming languages, Qbasic also offers extended precision (if you know where to look). I also suspect that many programmes specifically designed for PCs make use of the extra (3?) bits that are built into the architecture of the processor, whereas those that originate from Unix will use "standard" IEEE double precision.

But it's rather unkind* to call this a flaw unless you are dealing in extraordinarily large integers (not, SFIK, ever needed for accounting). Every non-binary calculation will have a numerical limit, and IEEE double precision is pretty standard.

*Me defending Microsoft - that would be a first - so you must remember that the structure you are complaining about originates elsewhere.

Fyz

QBASIC can do 64 bit floating point variables (if that answers the point ?). I have quite a nice desktop calc (my secret little helper) which is somewhat more useful.

I use INT with Qbasic (as a partial step) , but don't really understand your point . What is the problem with tracking where the decimal point should go in a multiplication ?

64-bit is ambiguous - it can be either IEEE double precision (same as the spreadsheets), or it can be 64-bit plus exponent plus sign (that's twelve bits better, but not always enough for some of my calculations*). I've never (yet) found 128-bit plus exponent plus sign to be inadequate for a practical calculation - so that's what I use whenever my back-of-envelope and standard route disagree.

There's no problem with tracking where decimal points should go - the issue was that integer arithmetic processors generally give more precision as a matter of course. The crudest integer arithmetic procedures tend to store the same number of Bytes (8) as floating point, and therefore give the extra 11-bits of precision because they don't "waste" the bits on exponents; however, as these are limited on absolute size (just 9E18), it is not uncommon for integer procedures to use variable lengths - in which case they retain absolute precision at all available magnitudes.

Fyz

Fyz

*High-Q processes generate ill-conditioned matrices that require ridiculous precisions.

They are useful...especially if you can't find a hardware one...or the one you do find hasn't the functions you need.

I'm sure we all use the net for finding obscure data...

How on earth would anyone know BSP drill & tap sizes otherwise!?

I had a shufti at the.... thread of death ...jeez am I glad I wasn't sucked into that one! Nice to know that I'm not the only one who finds the occaisional argument.

On that note..If more people added a bit more in their profile...sympathetic discourse might be easier?! (It's bad enough with totally unknown Guests...but it's nice if we can get to know the regulars a bit better)....

By the way, I'm a petite 8 stone blonde with a big bust (Of Newton on the sideboard)

Thanks for your comments -- I too now need charts for various tap/drill information you could fill a book -- Oh yeah "BOOKS", I do use "Machinery Handbook" for reference on a regular basis for all of my machine work questions.

Thanks

Just for you Del ;

I must , I must , I must increase my bust.

Hey I have combined topicality and humour. This is a new experience to me.

Thanks...most useful...now where do buy those stillettos in the more manly sizes?

I'd nearly forgotten those ! My wife swears blind she saw these stiletto's that have a folding heel (probably on GMTV) but so far I have been unable to locate them. It sounds like a brilliant product. Just think how many times you have seen some gorgeous secretary rushing to work who ends up on the floor , legs akimbo. Hang on , why would I want to find something that stops that.. Project on hold.

< sorry any ladies reading - I have appalling humour >

Well built male .GSOH.OCAH.ROFLMAO.Suave,Sophisticated . lots of dosh.inveterate lier.wtm female. call:sadguy@inkitchenatparties.com

Do you mean 8-pints stoned? (Was that you at the Rising Sun?)

ietech, If it weren't for calculators, I would have been a computer nerd long before I did. Why, because calculators made me fear they would make my brain lazy and not able to imprint calculations and strategies, so I stayed away for too many years. I agree with the posts that disagreed with the use of calculators. That's why we lag in computational skills and the scientific knowledge to exceed countries that insist calculations be "brain-monitored"

Thanks for taking the time to reply, that is why I posted this question to see how folks feel about this. Particularly, I was interested in the blanket statement that MOST folks on CR4 are not interested in or use on line calculators (not a quote here just a paraphrase of the comment posted in my original question).

Personally I have never even tried to remember formulae of any kind -- too many of them for me. Before computers and even calculators, I always kept a cheat sheet for calculations that I knew I would need to make for my jobs. I still have those sheets but find it more convenient and less time consuming to use on line calcs. If my results are of a critical nature I will manually do the calculations on paper and double check with a calculator, although those are far and few between these days for me.

But that is just me others obviously use different methods.

Thanks again.

I agree with you about remembering formulae - if I can't derive them, I probably don't understand what I'm doing (like most of the time)

Fyz

I remember getting the formula for quadratic equations drummed into me by rote at School. If they'd taken a short time to explain it's derivation it would have opened my eyes up a lot earlier. Some Of Harrys Cows And Horses Trod On Arthur has it's place , but other things are worth a bit of understanding. Simon Singh gives a great illustration of (X + 1 )³ in one of his books. I wasted ages (years ago) trying to remember the expanssion or working it out . I guess School teachers aren't always well qualified , and don't have time to dish out the learning as much as they would like.

"don't have time to dish out the learning"

Rubbish! The time spent on repetitious rote learning that goes on in most classrooms would be far better spent going through the principles so the stuff makes sense. Understanding often makes rotework unnecessary - and when you really do have to remember something, it's often a great deal easier if you understood the background in the first instance.

The real problem is the lack of proper understanding of many (certainly not all - some are terrific) teachers. When combined with arrogance, that is simply deadly. (As an example, just look back at the contribution (?) of one of the teachers to the fan-on-sailing_boat problem)

Fyz

Are you feeling unwell ?

Teacher: " Repeat. minus b plus or minus the square root of b squared - four a c all over 2 a "

<drone , drone , drone.....>

< 30 minutes>

Teacher: " OK , class dismissed (thank gawd I've finished the marking)"

It does happen you know. I acknowledge that the vast majority are better than that , and some even take 30 minutes to illustrate the origin of the equation.

On the other hand , teaching the times table by rote enables children to use it for practical purpose. Number theory is a bit much for pre-teens , so giving them a tool without finer understanding enables them to grasp other areas of mathematics.

I don't think people can be 'taught' but they can 'learn'. There is a major difference.

I suspect I did not convey my meaning clearly. Rote is not 'learning' , it is 'teaching'. A principle understood is 'learning'.

Set theory has been presented as young as five, and does not appear to present problems. Extending that to basic numbers is also not difficult.

It is not that uncommon for well-taught kids to develop long division before they have learned their tables - and it gives them a context and incentive for doing so. OK, so the psychologist who was investigating childrens' capabilities for his PhD was an exceptional teacher, but that is how it can be done - and should be for those whom it suits.

Fyz

Set theory has been presented as young as five......

.........that is how it can be done - and should be for those whom it suits.

Ok , Ive been a bit selective in the pasting there , bit it's a contentious issue. At what age would you select those 'suited'.

I am probably somewhat biased , as my teachers deemed me to be too stupid to sit any level of maths exam until I was 15 . The teaching I recieved was in accordance. I managed to get over this by personal study (and an excellent non-teacher , who happened to be an Engineer). The fact that I can reasonably hold my own is not due to any formal teaching input. I'll send you a message to expand on something here (+ a possibly a useful bit of info for your calcs)

Kris

Kris