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Software is not magic. It is like any other tool or item of test equipment that has its limits and you really need to have an idea of what/where they are.

Not just software tbh, I spent a short time teaching this rubbish at college and I couldn't believe how many couldn't use a calculator, but more importantly didn't understand whether the answer was slightly right or complete nonsense!

I guess 5-6 in one class when asked for the sin of 30 degrees, instead of getting 0.5 gave answers in the 10's if not hundreds!!! *

You should really have some understanding of the sort of answer, not just take it as read!

Even doing the shopping, I have an idea of what the bill should be!

*
Just for the pedants I know sin can go beyond +/- 1.0 if one looks at the complex domain - but this was a simple creation of a sine wave from 360 deg in steps, and a number couldn't even use a calculator for 10, 20,30,40..360 degrees!
 
I got out my pen and paper, labelled i1 and i2 and started writing i1=...

Then I thought - I feel really good. I am having a pain-free morning, I have a museum to build, so I ought to get one with that. And I started work on a different electrical puzzle: Finding a 15,000 square foot building to fill with electrical machinery. That one, unfortunately, can't be solved by superposition!
 
This is going to sound really old... but when those casios scientific calculators first came out with the red leds that ate batteries, my friend at school bought one ( i could not afford one) so when in class i used to race him to the answers , me doing it either in my head or on paper, him bashing away at the keys. It was in the good old days when you had to show all your working out, so there was no time penalty effect for the way i did it. I carried on like this all through secondary school and local college but when i eventually went to Uni i had to buy one as the lecturer kindly informed me i had no chance in the exams without a calculator, i was gutted, lol
 
My first "proper" calculator was a texas ti-58, I bought when I started university, you could write programs on it, and insert special (eprom) cartridges, at the time I think it was the only one that could use cosh, sinh and the like.

Although I have real difficulties using modern calculators tbh.

I think my way through equations, and that doesn't suit modern calculators, which expect the user to be copying an equation from a book.

So say I want to calculate the current into a load of two parallel resistors of 10 ohm, each supplied by 5v (not withstanding we can all do that in our heads), I would do the 10 + 10 part - do 1/x then x by 10 x 10 (which would give 5 ohm) then 1/x (0.2) then multiply by 5v to get 1A.

Just not possible now, instead you have to enter the equation v/(r1 x r2/(r1 + r2)) ans.

Not how my brain works!
 
My old school taught maths going from Lowest digit to highest, i..e from the right to the left. My brain does not like that so i have always done it from left to right. Sometimes i do wonder if schools realise there is more than one way to add up
 
I sometimes see slide rules in the charity shops and it reminds me of precalculator. At school we were learning slide rules and using anti/log tables which I don't think they do nowadays do they? Slide rules, I just think they are so clever. I asked my teacher what was the answer to 10 x 10 to the power of 10. Mrs. White as I recall, a flurry of the log/anti log tables and she did it! I was captivated and impressed and determined to learn the mysteries of those pages, alas fair reader, I never did.
 
I sometimes see slide rules in the charity shops and it reminds me of precalculator. At school we were learning slide rules and using anti/log tables which I don't think they do nowadays do they? Slide rules, I just think they are so clever. I asked my teacher what was the answer to 10 x 10 to the power of 10. Mrs. White as I recall, a flurry of the log/anti log tables and she did it! I was captivated and impressed and determined to learn the mysteries of those pages, alas fair reader, I never did.
Ten to ten, ten to ten, ten to ten ten ten.......................Lone Ranger on his abacus??
 
When I replaced my old Casio with a newer one I was really disappointed to see they revered the order of entry (oh-er matron!) as I was used to the older method when you used the function key to compute the action on the current display value.
Exactly!!!

Mine was/is a Casio, even the same model number, just a newer version.

I find it very difficult to use.

It used to be if you want the sine of 30 you entered 30 then sin, now you enter sin( then 30

The first is how my brain works, calculate the inner bit, then take the sine !
 
Balls... I was trying to work out R3! 69.13mW for that one.
That was good fun though, thanks.
 
It used to be if you want the sine of 30 you entered 30 then sin, now you enter sin( then 30

The first is how my brain works, calculate the inner bit, then take the sine !
The older models worked very much like a CPU with the display as the accumulator register that stuff happened to/from.

Actually that is another thing to throw in to the discussion - doing such electrical circuit mesh analysis by hand is similar to assembly language programming. Anyone who writes software should be able to do it and understand it so they grasp the basics, but nobody in their right mind uses it for anything where it could be done in a higher level language.
 
The older models worked very much like a CPU with the display as the accumulator register that stuff happened to/from.

Actually that is another thing to throw in to the discussion - doing such electrical circuit mesh analysis by hand is similar to assembly language programming. Anyone who writes software should be able to do it and understand it so they grasp the basics, but nobody in their right mind uses it for anything where it could be done in a higher level language.
I think a lot is to do with how we oldies think about maths.

If I am adding a list of say 10 numbers up, I do it in stages:
5+26= (31) +100= (131) +20= (331) ... Hang on, that's wrong... I must have done something wrong. So I start again getting a total for the 10 as say 606 - and am fairly assured the answer is correct.

Whereas today, people just punch the 10 numbers 5+26+100+20..... = 786 - It must be right I did it on a calculator.

Modern calculators suit this latter method.
 

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