SmartmanApps, Unfortunately some calculators, such as Google’s will ignore your brackets and put in their own anyway. You just gotta find a decent calculator in the first place.
EmrysOfTheValley, https://beehaw.org/pictrs/image/48023ee9-d7b3-4853-b1b5-60c453c72d4f.webp
It is also frustrating when different calculators have different orders of operations and dont tell you.
SmartmanApps, It is also frustrating when different calculators have different orders of operations and dont tell you.
Yeah, but to be fair most of them do tell you the order of operations they use, they just bury it in a million lines of text about it. If they could all just check with some Maths teachers/textbooks first then it wouldn’t be necessary. Instead we’re left trying to work out which ones are right and which ones aren’t. Any calculator that gives you an option to switch on/off “implicit multiplication”, then just run as fast as you can the other way! :-)
unlucky, me using sbcl for everything
EunieIsTheBus, (edited ) I recall that there is a myriad of memes of the form ‘what is 4-2*3’ under which there is always a never ending discussion of confidently incorrect dumbasses denying the existence of the multiplication before addition rule.
So your suspicion is at least not unreasonable
SmartmanApps,
spongeborgcubepants, Is the title a Requiem for a Dream reference?
7heo, (> (explicit) (implicit))
FatTony, (edited ) My calculator says -2² = -4, so yeah…
ByGourou, Isn’t the “-” order of operations the same as a multiply ? I think I learned powers take priority over the “-” so your calculator would be right.
But either way if it can cause confusion you should use parentheses.
TonyTonyChopper, Every calculator I’ve used has separate negative and subtraction keys for this purpose. There is no order of operations to follow, it’s just a squaring a number
SmartmanApps, it’s just a squaring a number
The number being squared is 4, unless you put (-4)², otherwise it’s 4² with a minus sign.
ByGourou, (edited ) I learned negative as being a separate operation where we need to apply the order of operations. I think it was something like : -2 is a diminutive for -1x2 so it uses the order of operations of a multiplication.
My calculator is the official one used in schools in France (ti-83 premium ce) and it says -2^2 = -4 with the negative key. I don’t think it would make a mistake in such a simple concept.But whatever these concepts can change depending on the field, country, level of education. What I mean is : it’s unclear, so use parentheses. So (-2)^2 or -(2^2) are the correct ways to write it.
SmartmanApps, I think it was something like : -2 is a diminutive for -1x2
Correct. Things that are usually left out of Maths expressions are plus signs, ones as multipliers/indices, and un-needed brackets. e.g. I could more fully write this as -1(4)², but that just simplifies to -4²
SmartmanApps, I think I learned powers take priority over the “-”
Yes, Exponents is the 2nd-highest precedence (after Brackets) - BEDMAS.
Ultraviolet, I would never write -n². Either ‐(n²) or (-n)². Order of operations shouldn’t be some sort of gotcha to trick people into misinterpreting you, it’s the intuitive reading of a well constructed mathematical expression.
SmartmanApps, Either ‐(n²) or (-n)². Order of operations shouldn’t be some sort of gotcha to trick people into misinterpreting you
It isn’t. With ‐(n²), n² is already a single term, so the brackets aren’t needed.
SmartmanApps, My calculator says -2² = -4
That’s correct
lolcatnip, (edited ) I’ve never seen a calculator that had bracket keys but didn’t implement the conventional order of operations.
But anyway, I’m on Team RPN.
masterspace, (edited ) plus.maths.org/content/pemdas-paradox
Even two casios won’t give you the same answer:
lolcatnip, Ah, I wasn’t thinking of calculators that let you type in a full expression. When I was in school, only fancy graphing calculators had that feature. A typical scientific calculator didn’t have juxtaposition, so you’d have to enter 6÷2(1+2) as 6÷2×(1+2), and you’d get 9 as the answer because ÷ and × have equal precedence and just go left to right.
SmartmanApps, A typical scientific calculator didn’t have juxtaposition, so you’d have to enter 6÷2(1+2) as 6÷2×(1+2)
That’s not true
you’d get 9 as the answer because ÷ and × have equal precedence and just go left to right
Well, more precisely you broke up the single term 2(1+2) into 2 terms - 2 and (1+2) - when you inserted the multiplication symbol, which sends the (1+2) from being in the denominator to being in the numerator. Terms are separated by operators and joined by grouping symbols.
lolcatnip, I’m not sure what you’re getting at with your source. I’m taking about physical, non-graphic scientific calculators from the 1990s.
SmartmanApps, (edited ) I’m taking about physical, non-graphic scientific calculators from the 1990s.
Yep, exact same as the calculator in the linked thread. The expression entered was 6÷2(1+2).
SmartmanApps, There’s no pemdas paradox, just people who have forgotten the order of operations rules
Even two casios won’t give you the same answer:
The one on the right is an old model. As far as I’m aware Casio no longer make any models that still give the wrong answer.
https://programming.dev/pictrs/image/92eab14c-a98b-4aab-82ec-f1e1611d70da.png
isolatedscotch, my dumb ass reading this: “Team rock paper nscissors”
lolcatnip, RTS = rock taper scissors FPS = frock paper scissors
SmartmanApps, I’ve never seen a calculator that had bracket keys but didn’t implement the conventional order of operations.
I’ve seen plenty
ArcticAmphibian, $((A+B))
Jakylla, Gotta use Lisp notation to be sure
MeDuViNoX, (‿!‿) (‿O‿)
The_Cunt_of_Monte_Cristo, ( . ) ( . ) ( . Y . )
ASeriesOfPoorChoices, back and forth, forever.
RinseDrizzle, Suuuuuch a weird movie lol
Kowowow, Ooh I love brackets
Lemmy_Cook, I feel this in my bones
mathic, I, my head, shake.
- RPN user
rockerface, Also known as: Japanese speaker
SmoothLiquidation, This is why every calculator should be a RPN calculator.
lemmyng, I still have my HP 48 series calculator. It’s a sturdy beast.
SmartmanApps, This is why every calculator should be a RPN calculator
No, this is why programmers should (re)learn the order of operations rules before writing a calculator.
ooli, I just used the calc on window… it cannot respect order of operation. Any simple calculator from 1980 was better than that
SmartmanApps, I just used the calc on window… it cannot respect order of operation
Yeah, I’ve tried several times to get Microsoft to fix their calculators. I’ve given up trying now - eventually you have to stop banging your head against the wall.
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