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Old 2021-10-12, 21:04   #23
a1call
 
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Quote:
Originally Posted by EdH View Post
Object A is a cube and object B is a sphere. . .
Good point.
A correction/update is due:

That is as meaningless as saying:
Cubic-Object-A has a volume that spans from -∞ to ∞ along axes x, y, and z.
Object-B has a volume greater than Object-A

Last fiddled with by a1call on 2021-10-12 at 21:05
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Old 2021-10-13, 07:26   #24
LaurV
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Don't need to go so far like creating huge stones, just take the bible and read it, to find out that god not only is not almighty, but it seems totally stupid, and most of the time full of envy, pride, ill intended, every second page. First example of the god being not-almighty is when he went into the garden of Eden and didn't have any freaking idea where Adam was, he had to look for him, and at the end ask where he was, after he couldn't find him (Adam was hidden because after eating the apple he became self-aware and he found out he was naked, therefore he was ashamed). And by the way, what the hack was god doing when Adam and Eve were eating the apple? Can't he see anything?

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Old 2021-10-13, 15:15   #25
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Indeed. His omniscience suggests that it is necessary to substantially limit both omnipotence and omniscience. and then holy Bible marasmus and mersenneforum are not far away

I asked my neighbor
-What is the likelihood of meeting a Dinosaur (T-Rex) on the street?
- =50%
-How the hell is that possible?
-Well, either you will meet, or you will NOT meet
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Old 2021-10-16, 07:26   #26
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Quote:
Originally Posted by RomanM View Post
50%
Haha is your neighbor's name Marilyn?
(and yes, that's the correct answer)
(edit: for clarity, she was asked that in a radio show many years ago, when she was talking about the fact that probabilities don't have memory, and that we are tempted to bring our experience into judging things which are pure math, where our past experience has no place - I think it was about Monty Hall problem, "how about if the host tries to cheat me")

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Old 2021-10-16, 07:54   #27
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Preferably, stop texting with the neighbours and take your chances on the street.
If there is a T-Rex, please snap a photo and share it with us.
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Old 2021-12-05, 13:52   #28
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Regarding operator precedence, I came across this today. Pretty cool!

40 - 32 ÷ 2 = 4!

Last fiddled with by ZFR on 2021-12-05 at 13:52
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Old 2021-12-06, 19:20   #29
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Default 8/2*(2+2)

I was asked what the answer to this was at work and I reflexively said "1." I learned shortly thereafter that this was a "thing" on the internet a while ago, https://mindyourdecisions.com/blog/2...wer-explained/
**Disclaimer-I don't endorse the link posted but it contains a decent presentation that's lacking in some other sites.

At the time, I looked at the expression again and changed my response to 16 but this didn't "feel" right. BEDMAS, PEMDAS....
Within the forum, a quick search turned up empty meaning I missed it or it hasn't been posted.
Ambiguities resolved by "convention, tradition or common acceptance" cause me to raise an eyebrow or two.

Is anyone aware of an "unambiguous" physical example showing there is only one unique interpretation or better, is there a proof illustrating the same unique logical arrow?

Are there other such "situations" within mathematical notation that are resolved by "convention, tradition or common acceptance" that aren't really questioned ...except by children?
Dover has a decent two tome book by F. Cajori regarding the evolution of mathematical notation and there are other sources. I've encountered such things before (ie. is 1, -1 prime?) and when programming binary or quantum code you really need to have a handle on your conceptual tools...and not do what Lewis Black does when portraying someone using bafflegab to justify the reasoning involved.

**Thank you to the moderator who moved this post where it belongs!

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Old 2021-12-06, 19:41   #30
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Apart from parenthesis and operator precedence, things are parsed left to right, except for a few like "=" and "^" in Pari/GP which are right to left.

Last fiddled with by paulunderwood on 2021-12-06 at 19:53
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Old 2021-12-06, 21:29   #31
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Quote:
Originally Posted by paulunderwood View Post
Apart from parenthesis and operator precedence, things are parsed left to right, except for a few like "=" and "^" in Pari/GP which are right to left.
I just read through the thread and it didn't help.
Question: Can operator precedence be measured or quantified? (cf. Lord Kelvi..something to the effect where if it can't be measured it can't it be understood).
To clarify, Horner Form, RPN, Karatsuba..can minimize the number of operations required;Boolean circuits can be resolved into alternative logic gates (Richard Kaye..https://minesweepergame.com/math/the...eeper-2012.pdf). There seems to be something lacking, something implicit which needs improvement.
A temporal component (which requires justification) could be considered, and certain logical forms do exist with this constraint. The minesweeper component was an example of an application of the logic, a derived result.

I haven't looked at this from the point of view of automated Th'm provers (ACL2) but even within quantum calculations there's probability rather than interpretative ambiguity.

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Old 2021-12-06, 23:05   #32
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The context free languages are precisely those for which there exists a non-deterministic pushdown automaton.
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Old 2021-12-07, 01:39   #33
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Quote:
Originally Posted by paulunderwood View Post
Apart from parenthesis and operator precedence, things are parsed left to right, except for a few like "=" and "^" in Pari/GP which are right to left.
My pet peeve for Pari/GP is that all operators in logical operations are estimated (very different from C or even perl - in them if you write if(a && b) {} -- and a is false, b is not computed. In Pari it is!!).

Example: you write a scirpt that tests every prime that ends with "11" and if that test passes, prints the value.
You will be wrong to write:
myHeavyTest(n)={...something...; return bla;} \\ bla is 0 or non-zero
forprime(p=11,10^8,if(p%100==11 && myHeavyTest(p), print1(p" ")))

And then wait and wait and it is still running. Why? because myHeavyTest(p) is being run every time!

What one should write in Pari is
myHeavyTest(n)={...something...; return bla;} \\ bla is 0 or non-zero
forprime(p=11,10^8,if(p%100==11,if(myHeavyTest(p), print1(p" "))))


Yeah, I know, it seems unrelated, but it is as good a place as any other to make people more careful when using Pari (or when referring to Pari as if it were some sort of a gold standard that helps one tie-break some decisions about how to implement well).
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