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Logarithmic Tables. 8
- Thread starter keano
- Start date
SlideRuleEra
Structural
![[smile]](/data/assets/smilies/smile.gif "[smile] [smile]")
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- Thread starter
- #4
IRstuff.
Do you not think your becoming just a number puncher inputing variables pressing return and gething an answer
with out realy knowing how it was derived.
I see young grad's coming out not able to add or subtract
in their head's. It's "oh where'd I leave my cal or I'll use the computer to find the answer."
Do you not think your becoming just a number puncher inputing variables pressing return and gething an answer
with out realy knowing how it was derived.
I see young grad's coming out not able to add or subtract
in their head's. It's "oh where'd I leave my cal or I'll use the computer to find the answer."
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GregLocock
Automotive
I can work out logs (roughly) in my head. Does that count?
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
And do you still expect carpenters to be able to use their fists to hammer nails?
A calculator, or in deference to SRE a sliderule, is simply a tool. The fact that the overall quality of graduates is decreasing is no reason to require using log tables.
Most modern cars cannot be worked on, nor do most people know anything about the inner workings thereof. Does that mean they shouldn't be allowed to drive?
Most children do not have calculators in 1st-3rd grades, which is where they're supposed to learn 4-function math. The problem is the training, not the tools.
Furthermore, it's absurd to think that using log tables will somehow make you a better engineer. Using log tables simply makes you a slower engineer. The first one to get the correct answer is the winner, regardless of how he does it.
A good engineer uses the appropriate tool for the job. That's why, Greg's comment not withstanding, he knows how to run Matlab, Mathcad and Excel.
TTFN
A calculator, or in deference to SRE a sliderule, is simply a tool. The fact that the overall quality of graduates is decreasing is no reason to require using log tables.
Most modern cars cannot be worked on, nor do most people know anything about the inner workings thereof. Does that mean they shouldn't be allowed to drive?
Most children do not have calculators in 1st-3rd grades, which is where they're supposed to learn 4-function math. The problem is the training, not the tools.
Furthermore, it's absurd to think that using log tables will somehow make you a better engineer. Using log tables simply makes you a slower engineer. The first one to get the correct answer is the winner, regardless of how he does it.
A good engineer uses the appropriate tool for the job. That's why, Greg's comment not withstanding, he knows how to run Matlab, Mathcad and Excel.
TTFN
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keano,
"Do you not think your becoming just a number puncher inputing variables pressing return and gething an answer
with out realy knowing how it was derived."
How do log tables help you to know how an answer is derived? If you are that keen then why not do the Taylor series expansion, then you can be like the constipated mathematician (who sat down and worked it out with a pencil. He he!).
The key thing is to be able to do a quick rough mental estimate to know if the answer on the calculator screen is way out or not (did I type 10E6 or 10E-6?).
I often use Matlab to do simple calcs and I often snigger to myself while doing it (All this computing power, all this software just to multiply two numbers). However, this is not overkill. It is simply that Matlab is open on my desktop 99% of the working day and it is the quickest way of doing it.
What bugs me about computers/calculators is the lack of a standard notation for logatithms. My calculator has "log" and "ln" for log to base 10 and log to base e, whereas Matlab has "log10" and "log".
M
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Dr Michael F Platten
"Do you not think your becoming just a number puncher inputing variables pressing return and gething an answer
with out realy knowing how it was derived."
How do log tables help you to know how an answer is derived? If you are that keen then why not do the Taylor series expansion, then you can be like the constipated mathematician (who sat down and worked it out with a pencil. He he!).
The key thing is to be able to do a quick rough mental estimate to know if the answer on the calculator screen is way out or not (did I type 10E6 or 10E-6?).
I often use Matlab to do simple calcs and I often snigger to myself while doing it (All this computing power, all this software just to multiply two numbers). However, this is not overkill. It is simply that Matlab is open on my desktop 99% of the working day and it is the quickest way of doing it.
What bugs me about computers/calculators is the lack of a standard notation for logatithms. My calculator has "log" and "ln" for log to base 10 and log to base e, whereas Matlab has "log10" and "log".
M
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Dr Michael F Platten
MikeyP
A star for you for the statement on the key as being able to independently know if the answer received is close to correct.
After all, I make quite a bit of my living off of dealing with what goes wrong. Quite often I have found it to be the results of a basic "OOPs".
Regards,
A star for you for the statement on the key as being able to independently know if the answer received is close to correct.
After all, I make quite a bit of my living off of dealing with what goes wrong. Quite often I have found it to be the results of a basic "OOPs".
Regards,
Real engineers use an abacus...
They also run to work up hill both ways through the snow bare footed with no lunch with angry polar bears chasing them.
Doing math with a pencil is for weenies, can't you remember the number until the end of the calc?
There's a LONG stretch between working out logarithms with a calculator and being a mindless number cruncher unaware of the grand math floating around our heads.
I can still ride my bicycle and soil myself and through food at mommy, but I found a better way to do things.
They also run to work up hill both ways through the snow bare footed with no lunch with angry polar bears chasing them.
Doing math with a pencil is for weenies, can't you remember the number until the end of the calc?
There's a LONG stretch between working out logarithms with a calculator and being a mindless number cruncher unaware of the grand math floating around our heads.
I can still ride my bicycle and soil myself and through food at mommy, but I found a better way to do things.
I can still use logarithmic tables and for multiplication I don't even use a logarithmic table. I just do it manually. What is the big deal? It is nothing else but nostalgia.
I prefer calculator over a logarithmic table.
PS: If I can get something better in future, I will just throw away my calculator.
I prefer calculator over a logarithmic table.
PS: If I can get something better in future, I will just throw away my calculator.
Don't run down Logarithms.
Got drafted while a CO-OP, came out of the Army broke, no jobs, thousands laid off in the local mills. Got a hint of a job in Florida, one of probably 20 interviewees for a very nice job of Senior Engineering Technician at very good pay and I got the job because I was the one applicant that could easily handle Logarithms. Stayed there 42 yrs and got to put my Logarithmic skills to work more than I had bargained for. Damn sure was glad to see the first electronic calculator that had 3 significant digits. That made everyone happy until the 5 digit, then the 9 digit came along. My question was always “What engineer needs 9 digits when 3 will do?” The Scripto mechanical pencil came into being with 5 digit calculator.
Got drafted while a CO-OP, came out of the Army broke, no jobs, thousands laid off in the local mills. Got a hint of a job in Florida, one of probably 20 interviewees for a very nice job of Senior Engineering Technician at very good pay and I got the job because I was the one applicant that could easily handle Logarithms. Stayed there 42 yrs and got to put my Logarithmic skills to work more than I had bargained for. Damn sure was glad to see the first electronic calculator that had 3 significant digits. That made everyone happy until the 5 digit, then the 9 digit came along. My question was always “What engineer needs 9 digits when 3 will do?” The Scripto mechanical pencil came into being with 5 digit calculator.
I had a boss holler at me for using a slide rule (Napier's Logs). This was a few years after personal computers got established. I had set up proportionality ratios so that I could read several answers conveniently at the same time. What a jerk!
Did the need to multiply large numbers fast correspond with the need for better navigation tools? Sea captains in the 1600s on up were by necessity good mathematicians. Was Napier responding to a need by Britain’s expanding Navy and merchant marine? Accurate chronometers were developed in response to the Royal Navy’s need.
A good set of log tables were as prized by the captain of a ship in the 18th century as a GPS receiver is today.
The slide rule was originally developed to help artillery officers calculate range and elevations settings for cannon.
Even in the old days the death and destruction business drove a lot of technology.
There is an interesting history of mathematics, including logarithms, in Mathematics for the Million by Lancelot Hogben. His socialist leanings clearly dictate his perspective, but it is interesting all the same.
He approaches logarithms from the point of view of angle addition, i.e., the sine of an angle might be more easily calculated as the sum of two known angles than as the angle itself--a sort of transform.
The calculations required for celestial navigation make the PE exam look like a walk in the park.
William
He approaches logarithms from the point of view of angle addition, i.e., the sine of an angle might be more easily calculated as the sum of two known angles than as the angle itself--a sort of transform.
The calculations required for celestial navigation make the PE exam look like a walk in the park.
William
I was in the next-to-last class that used slide rules in the Mare Island Nuclear Power School. The following class used HP calculators. I asked one of the instructors why they had made the class so much "easier". He said "the concepts are the same, we just don't have to take as much care to make the numbers slide-rule friendly."
As was said before, the slide rule was just a convenient way to present the log tables, and a calculator is just a convenient way to slide the tables around. I think an engineer needs to know what values to manipulate in what way--the act of the manipulation is simple mechanics and I don't feel a bit the less competent engineer for not having opened one of the damn things in 30+ years.
David Simpson, PE
MuleShoe Engineering
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
The Plural of "anecdote" is not "data"
As was said before, the slide rule was just a convenient way to present the log tables, and a calculator is just a convenient way to slide the tables around. I think an engineer needs to know what values to manipulate in what way--the act of the manipulation is simple mechanics and I don't feel a bit the less competent engineer for not having opened one of the damn things in 30+ years.
David Simpson, PE
MuleShoe Engineering
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
The Plural of "anecdote" is not "data"
VirtualEngineer
Structural
Like IRstuff, I too like Mathcad.
I know some people like to create worksheets in Lotus or Excell for repetitive calculations. But I believe Mathcad is far superior to use.
I've created numerous worksheets for designing all sorts of conditions. The thing I like about Mathcad is you can see your formulas; in fact, the formulas you see are the engines driving the calculations.
Once created your worksheet is good documentation for your calculations, and you have a worksheet you can reuse on similar projects.
In many ways I have been able to put my calculator on the back burner, because it is so easy to write a Mathcad worksheet.
I highly recommend this program for all engineers.
![[thumbsup2]](/data/assets/smilies/thumbsup2.gif "[thumbsup2] [thumbsup2]")
I agree with VE's comments on Excel. Many a worksheet has started off as a simple engineering calc and ended up as a monster that is difficult to modify and virtually impossible to check.
There's been mentions here of both Mathcad and Matlab - are they much the same thing?
There's been mentions here of both Mathcad and Matlab - are they much the same thing?
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