I, my head, shake.
- RPN user
Also known as: Japanese speaker
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.
https://plus.maths.org/content/pemdas-paradox
Even two casinos won’t give you the same answer:
https://plus.maths.org/content/sites/plus.maths.org/files/articles/2019/pemdas/calculators.png
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.
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.
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.
I’m not sure what you’re getting at with your source. I’m taking about physical, non-graphic scientific calculators from the 1990s.
my dumb ass reading this: “Team rock paper nscissors”
RTS = rock taper scissors
FPS = frock paper scissors
I’ve never seen a calculator that had bracket keys but didn’t implement the conventional order of operations.
I’ve seen plenty
My calculator says -2² = -4, so yeah…
My calculator says -2² = -4
That’s correct
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.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
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.
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
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.
I think I learned powers take priority over the “-”
Yes, Exponents is the 2nd-highest precedence (after Brackets) - BEDMAS.
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.
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.
(‿!‿) (‿O‿)
( . ) ( . ) ( . Y . )
$((A+B))
Gotta use Lisp notation to be sure
As a software developer, the less ambiguous your notation is, the better it is for everyone involved. Not only will I use brackets, I’ll split my expression into multiple rows and use tabs to make it as readable as humanly possible. And maybe throw a comment or 2 if there’s still some black magic involved
Ok but that’s unrelated to putting some numbers and operations in a calculator. No one is going to proofread that. If anything, you simply calculate it again.
I genuinely hate being human for this stuff. So many things have such crazy computational shortcuts, it’s sometimes difficult to remember which part represents reality. Outside of the realm of math, where “imaginary” numbers are still a touch of enigma to me, so many algorithms are based on general assumptions about reality or the specific task, that the programmatic approach NEVER encapsulates the full scope of the problem.
As in, sometimes if you know EXACTLY how a tool works, you might still have no idea about the significance of that tool. Even in a universe where no one is lazy, and everyone wants to know “why?”, the answers are NOT forthcoming.
You’re a good human being.
As someone who used to code in Lisp, I’m all for excessive paranthesis use.
As a professor said, most programming languages don’t care about readability and whitespace. But we care because humans need it to parse meaning. Thus, write code for people, not for the machine. Always assume that someone with no knowledge of the context will have to debug it, and be kind to them. Because that someone might be you in six months when you have completely forgotten how the code works.
Source code is for humans, then the compiler turns it into code for machines.
Exactly. You read code way more times than you write it, so it makes all the sense in the world to prioritize readability.
Yep, if you’re writing code for a machine, just do it in binary to save compilation time (/s just in case). Also, you in six months will indeed be someone with no knowledge of the context. And every piece of code you think you write for one-time use is guaranteed to be reused every day for the next 5 years
And every piece of code you think you write for one-time use is guaranteed to be reused every day for the next 5 years
This. Always be kind to your future self.
Python forcing end of line and tabs kinda does. Add Black auto-formatter and it’s pretty good.
I’ve seen too many Python devs write out complex statements all on one crammed up line. Including some that are in the main docs.
Enforced whitespace is just one aspect of readable code. There are many others, and Python is no better at enforcing those than any other language.
That would probably make very long lines and black would automatically add returns to line with proper indentations. But it has a a limit for sure. If you chain many list comprehensions it’s going to be a mess.
Yeah I totally agree. You can minimize and optimize as part of your build procedure/compilation but the source code should be as readable as possible for humans.
I had someone submit a pull request recently that, in addition to their actual changes, also removed every single parenthesis that wasn’t strictly necessary in a file full of 3D math functions. I know it was probably the fault of an autoformatter they used, but I was still the most offended I’ve ever been at a pull request.
Autoformatter? More like obfuscator
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That almost seems cute next to the shit the obfuscated c contest pulls off. https://www.ioccc.org/years.html
Further up the thread, someone mentioned that writing good software is about communicating concepts to people, first and foremost.
This, code obfuscation, is what it looks like to communicate exclusively to the compiler instead.
For some context this is one of the winning entries:
#include <stdio.h>
#define N(a) “%”#a"$hhn" #define O(a,b) “%10$”#a"d"N(b) #define U “%10$.*37$d” #define G(a) “%”#a"$s" #define H(a,b) G(a)G(b) #define T(a) a a #define s(a) T(a)T(a) #define A(a) s(a)T(a)a #define n(a) A(a)a #define D(a) n(a)A(a) #define C(a) D(a)a #define R C(C(N(12)G(12))) #define o(a,b,c) C(H(a,a))D(G(a))C(H(b,b)G(b))n(G(b))O(32,c)R #define SS O(78,55)R “\n\033[2J\n%26$s”; #define E(a,b,c,d) H(a,b)G©O(253,11)R G(11)O(255,11)R H(11,d)N(d)O(253,35)R #define S(a,b) O(254,11)H(a,b)N(68)R G(68)O(255,68)N(12)H(12,68)G(67)N(67)
char* fmt = O(10,39)N(40)N(41)N(42)N(43)N(66)N(69)N(24)O(22,65)O(5,70)O(8,44)N( 45)N(46)N (47)N(48)N( 49)N( 50)N( 51)N(52)N(53 )O( 28, 54)O(5, 55) O(2, 56)O(3,57)O( 4,58 )O(13, 73)O(4, 71 )N( 72)O (20,59 )N(60)N(61)N( 62)N (63)N (64)R R E(1,2, 3,13 )E(4, 5,6,13)E(7,8,9 ,13)E(1,4 ,7,13)E (2,5,8, 13)E( 3,6,9,13)E(1,5, 9,13)E(3 ,5,7,13 )E(14,15, 16,23) E(17,18,19,23)E( 20, 21, 22,23)E (14,17,20,23)E(15, 18,21,23)E(16,19, 22 ,23)E( 14, 18, 22,23)E(16,18,20, 23)R U O(255 ,38)R G ( 38)O( 255,36) R H(13,23)O(255, 11)R H(11,36) O(254 ,36) R G( 36 ) O( 255,36)R S(1,14 )S(2,15)S(3, 16)S(4, 17 )S (5, 18)S(6, 19)S(7,20)S(8, 21)S(9 ,22)H(13,23 )H(36, 67 )N(11)R G(11)""O(255, 25 )R s(C(G(11) ))n (G( 11) )G( 11)N(54)R C( “aa”) s(A( G(25)))T (G(25))N (69)R o (14,1,26)o( 15, 2, 27)o (16,3,28 )o( 17,4, 29)o(18 ,5,30)o(19 ,6,31)o( 20,7,32)o (21,8,33)o (22 ,9, 34)n(C(U) )N( 68)R H( 36,13)G(23) N(11)R C(D( G(11))) D(G(11))G(68)N(68)R G(68)O(49,35)R H(13,23)G(67)N(11)R C(H(11,11)G( 11))A(G(11))C(H(36,36)G(36))s(G(36))O(32,58)R C(D(G(36)))A(G(36))SS
#define arg d+6,d+8,d+10,d+12,d+14,d+16,d+18,d+20,d+22,0,d+46,d+52,d+48,d+24,d
+26,d+28,d+30,d+32,d+34,d+36,d+38,d+40,d+50,(scanf(d+126,d+4),d+(6
-2)+18*(1-d[2]%2)+d[4]*2),d,d+66,d+68,d+70, d+78,d+80,d+82,d+90,d+
92,d+94,d+97,d+54,d[2],d+2,d+71,d+77,d+83,d+89,d+95,d+72,d+73,d+74
,d+75,d+76,d+84,d+85,d+86,d+87,d+88,d+100,d+101,d+96,d+102,d+99,d+
67,d+69,d+79,d+81,d+91,d+93,d+98,d+103,d+58,d+60,d+98,d+126,d+127,
d+128,d+129char d[538] = {1,0,10,0,10};
int main() { while(*d) printf(fmt, arg); }
If I cross my eyes hard enough on mobile… I imagine I can see dickbutt in there somewhere…
I tried to read that out loud and summoned something. Please help me, I’m scared.
I thought this was a simple piece of software?
Pinhead: No. It is a means by which to summon us.
this straight up looks like a chemical formula
Excel has entered the chat
For real though, I have written some truly monstrous operations in Excel.
What do you mean you want to use Excel to manage everyone’s calendars? And now you want to export that horribly built calendar management spreadsheet to Google Calendar? What do you mean you want the Google Calendar entries automatically formatted based on who is working on a particular day? I mean yes it’s possible but-…
VBA has made things so, so much easier since I started learning how to use it.
Calm down, Satan
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The one-liner: *parses HTML with a regex*
cthulhu fthagn
Well, this is exactly what mathematicians do.
Ok man. Wtf did I just watch…
I get it. We are here on the somehow dark side of the internet…
But THIS… without any context. i mean. Im questioning live here man. What do you want to express with that?
I’m pretty sure it’s just a reference to when the kid types ))<>((
Btw, it’s not from the dark side of the Internet. This was a very popular video at the time.
My husband showed me that video last night. It was very strange.
Somehow that clip is better than the fairly odd movie. I don’t think I could recommend it… But I think of the clip posted all the time. It’s so weird 😂. Some how they figured out creepy, funny, and somehow wholesome at once.
🤦♂️ read the post body, my lad.
Also works if you dont trust yourself with correctly ordering your operations.
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.
It is also frustrating when different calculators have different orders of operations and dont tell you.
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! :-)
Or, you know, you could simplify the terms?
sounds like work for a compooter
(> (explicit) (implicit))
(I used(LISP)one time((and it)permanently)changed the way I (operate(computers)))
Did it change it in a positive way?
Negative, as you feel bad anytime you use a language that isn’t lisp
Ooh I love brackets
I just used the calc on window… it cannot respect order of operation. Any simple calculator from 1980 was better than that
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.
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
