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 2021-09-30, 16:13 #12 a1call     "Rashid Naimi" Oct 2015 Remote to Here/There 2,207 Posts IMHO, the bigger issue is the daily corruption of Sciences by applying Democratic-Processes to them. At some point true Scientific-Authority by experts will be unrecoverable. Recently YouTube banned anti-vax content. As useful of a tool is Wikipedia, it is in desperate need of multilevel authoritarian control. Again, IMHO.
2021-09-30, 16:19   #13
Dr Sardonicus

Feb 2017
Nowhere

14FE16 Posts

Quote:
 Originally Posted by pepi37 I am very disappointed. I expected the math to be a little better defined after all :)
It's not the math. The individual operations of additon, subtraction, and multiplication are all defined for the integers. Division, except by zero, is defined for the rational numbers.

"Implicit operators" are not mathematically defined.

With "infix notation" (binary operators between operands, all operators explicit) the question of "operator precedence" (also not mathematically defined) becomes important, and explicit operators are essential, when you're telling a stupid machine to parse and evaluate an expression.

"Polish notation" and "Reverse Polish notation" (RPN) are unambiguous and eliminate the need for parentheses. I recall the grumbling about early HP "pocket calculators" using RPN instead of infix when they came out. There was also a limitation on how many operations could be "stacked."

(8/2)*(2+2) would be (I think!) 8 2 / 2 2 + *

8/(2*(2 + 2)) would be (I think!) 8 2 2 2 + * /

2021-10-06, 12:01   #14
Happy5214

"Alexander"
Nov 2008
The Alamo City

30B16 Posts

Quote:
 Originally Posted by Dr Sardonicus (8/2)*(2+2) would be (I think!) 8 2 / 2 2 + * 8/(2*(2 + 2)) would be (I think!) 8 2 2 2 + * /
I concur on the RPN order, and as someone who's dabbled a bit in Lisp-style languages, prefix/Polish notation is superior to infix as well, at least in CS. (Try getting the uninitiated to switch to it.)

FWIW, Wolfram Alpha returned 16 for the OP's expression, which IMHO is more correct than 1 per the left-to-right ordering of the (implicit) multiplication and division, though I'd rather see an explicit operator or parentheses myself.

 2021-10-06, 15:56 #15 M344587487     "Composite as Heck" Oct 2017 11011010112 Posts BIDMAS is what is taught in UK schools for precedence left to right: brackets indices divide multiply add subtract So the answer is 16, however this BBC page INCORRECTLY* defines BIDMAS by giving D and M equivalent precedence (ditto A and S), so even if you use BIDMAS it might not be the same as what someone else does: https://www.bbc.co.uk/bitesize/topic...ticles/zj29dxs *I don't care if they are right in their definition of BIDMAS (which alcall's link seems to back up), grouping different operations with equivalent precedence is nonsense and if computers existed when these rules were invented they'd do the sane thing and have a simple left to right convention. Why even bother teaching it as a string like that if you're going to mess it up with special-cased heathenry, good god.
2021-10-09, 03:20   #16
Batalov

"Serge"
Mar 2008
Phi(4,2^7658614+1)/2

25·3·101 Posts

Quote:
 Originally Posted by Batalov Welcome to the world of semantics! It is the same as (it sounds better in Russian) a some king's ruling that was passed down to minions: "behead not pardon" Imagine the confusion of the "project managers" of that time.
Another identical pun was just noted in the wild
"Вышла Windows 11: ставить нельзя ждать"

≈ "Windows 11 is out: install not wait"

 2021-10-11, 22:44 #17 greenskull Xebeche     Apr 2019 🌺🙏🌺 6728 Posts It's good that there is a plus in parentheses between the twos. If there was a minus, then some would get 0, and others - infinity.
 2021-10-12, 17:29 #18 RomanM   Jun 2021 2·23 Posts *** God is almighty. ok. Let God create a BIG Stone, that is too big to god can't lift by blessed god arms, ok Seems that God is not too Almighty??? No. it's obviously. He just do not do such things. Last fiddled with by RomanM on 2021-10-12 at 17:30
 2021-10-12, 17:55 #19 kruoli     "Oliver" Sep 2017 Porta Westfalica, DE 2·32·47 Posts If I would take that story: You cannot do that, because the premise that there is anything that god could not do is false, so it is not according to your "axioms" that there could be something created which he cannot lift. It is not a question if he could do it or not, there is already a contradiction and we have no way to proceed. That way, we can make no sensible point about anything, since we could follow anything from a false statement.
2021-10-12, 17:57   #20
slandrum

Jan 2021
California

2·32·17 Posts

Quote:
 Originally Posted by kruoli That way, we can make no sensible point about anything, since we could follow anything from a false statement.
Such as the existence of an all-powerful god which leads immediate contradictions?

2021-10-12, 20:30   #21
a1call

"Rashid Naimi"
Oct 2015
Remote to Here/There

220710 Posts

Quote:
 Originally Posted by RomanM God is almighty. ok. Let God create a BIG Stone, that is too big to god can't lift by blessed god arms, ok Seems that God is not too Almighty??? No. it's obviously. He just do not do such things.
Not sure how this is relevant to operation order, but mathematically speaking that is as meaningless as saying:

Object-A has a volume that spans from -∞ to ∞ along axes x, y, and z.
Object-B has a volume greater than Object-A

2021-10-12, 20:57   #22
EdH

"Ed Hall"
Dec 2009

2·11·191 Posts

Quote:
 Originally Posted by a1call Not sure how this is relevant to operation order, but mathematically speaking that is as meaningless as saying: Object-A has a volume that spans from -∞ to ∞ along axes x, y, and z. Object-B has a volume greater than Object-A
Object A is a cube and object B is a sphere. . .

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