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Math array rebuild

Anonymous Sun 15 Aug 08:33:41 2021 No.13521396 View Reply Original Report

Quoted By: >>13521604 >>13524238 >>13525155 >>13525268 >>13525396 >>13528098

Not a mathematician so forgive my limited understanding of math. I'm trying to learn.

Is the following possible in math?

input: 1+2+3+4=10

Can the values from input (ABCD) be deduced in the same order as input from the answer of 10?

Anonymous

Anonymous Sun 15 Aug 2021 08:40:47 No.13521407 Report

Quoted By: >>13521420

Not with addition because it's commutative (a+b=b+a), but non-commutative operators exist, eg matrix multiplication.

Anonymous

Anonymous Sun 15 Aug 2021 08:40:53 No.13521408 Report

Quoted By: >>13521420

Your question isn't clear at all

Anonymous

Anonymous Sun 15 Aug 2021 08:46:30 No.13521420 Report

Quoted By: >>13521434 >>13521486

>>13521407
Not understanding what some of these terms mean, am i correct to assume if I don't add but multiply, its possible? Can you recommend some reading material so I can learn?

>>13521408
What I'm trying to do is rebuild an array in the same order by only knowing the value of an array calculation.

Anonymous

Anonymous Sun 15 Aug 2021 08:57:20 No.13521434 Report

Quoted By: >>13521481

>>13521420
>am i correct to assume if I don't add but multiply, its possible?
No, of course not. Simply try adding or multiplying in a different order to see that you still get the same answer

Anonymous

Anonymous Sun 15 Aug 2021 09:21:38 No.13521481 Report

Quoted By: >>13521563 >>13521595

>>13521434
The answer is variable.

I'll attempt to re-explain with my education of high school maths.
I would like to have an array of values, do and equation to create an answer/hash then use the answer/ hash to rebuild the array in the same order as the original array

Anonymous

Anonymous Sun 15 Aug 2021 09:22:46 No.13521486 Report

Quoted By: >>13524232

>>13521420
It'd have to be multiplication of matrices, not normal numbers, and it can but wouldn't always give a unique answer. But matrices are just arrays of numbers so might be what you want.
Google linear algebra, vectors, matrix multiplication, inverse matrices. It's pretty fundamental stuff so there's loads of guides, start wherever you can understand.

Anonymous

Anonymous Sun 15 Aug 2021 10:05:04 No.13521563 Report

Quoted By: >>13521591

>>13521481
6*3*2=2*3*6 =3*3*4=36

Anonymous

Anonymous Sun 15 Aug 2021 10:23:08 No.13521591 Report

Quoted By: >>13525137

>>13521563
> 6*3*2=2*3*6 =3*3*4=36

This makes no sense to someone who does not understand math outside of simple arithmetic on a calculator. Can you explain what it means?

Anonymous

Anonymous Sun 15 Aug 2021 10:25:14 No.13521595 Report

Quoted By: >>13521619

>>13521481
>array of values, do and equation to create an answer/hash then use the answer/ hash to rebuild the array in the same order
Can you simply map 1, 2, 3, 4 to 1234 and back to 1, 2, 3, 4?

Anonymous

Anonymous Sun 15 Aug 2021 10:30:54 No.13521604 Report

Quoted By:

>>13521396
1+4=5
2+3=5
5+5=10

Anonymous

Anonymous Sun 15 Aug 2021 10:37:42 No.13521619 Report

Quoted By:

>>13521595
No,
array is size x and the original values are not known. But need to be rebuilt in sane order as original array.

Anonymous

Anonymous Mon 16 Aug 2021 03:32:28 No.13524220 Report

Quoted By:

bump

Anonymous

Anonymous Mon 16 Aug 2021 03:33:57 No.13524232 Report

Quoted By: >>13524358 >>13525040

>>13521486
>It'd have to be multiplication of matrices

Why does this make it more possible? It literally doesn't matter at all, there are still many potential solutions.

Anonymous

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Anonymous Mon 16 Aug 2021 03:35:28 No.13524238 Report

Quoted By: >>13525040

>>13521396
It's not possible mathematically but could you explain why you need to do this and simply can't print out the input?

I'm assuming you've lost access to either the raw data and/or source code and only have the output left?

Anonymous

Anonymous Mon 16 Aug 2021 04:34:44 No.13524358 Report

Quoted By: >>13525040 >>13525192

>>13524232
Depends what he's trying to do. Non-commutativity makes recovering the order possible. If input is limited to 10 digits, natural numbers, etc the potential solution space is small and easy to eliminate or you could even brute force it.

Anonymous

Anonymous Mon 16 Aug 2021 10:58:28 No.13525040 Report

Quoted By: >>13525070

OP here.

>>13524232
How so can you elaborate?

>>13524238
The assumption you have works. Although just wanted to learn something new. Why do you say impossible? Others have mentioned matrices as a possibility.

>>13524358
Essentially wish to have an array of size x do some equation to get an answer that then can be used to deduce the original array and in the same order assuming no knowledge of the original array apart from its size.

Anonymous

Anonymous Mon 16 Aug 2021 11:14:47 No.13525070 Report

Quoted By: >>13525089 >>13525094 >>13525127

>>13525040
>Why do you say impossible? Others have mentioned matrices as a possibility.
you're misunderstanding, if you have some inputs, passed through a function to generate your outputs, then the function must not be commutative (order of the inputs matter) and bijective (no two different inputs map to the same output/vice versa). If the function is commutative, as addition and multiplication are, then we can't figure out the order. (1+2+3 = 6, but also 2+1+3, and 3+2+1, etc.) if the function isn't bijective, like sum of inputs, we can't figure out the unordered input (5+5=10, but also 2+8, 3+3+4, 6+2+1+1, etc)

Anonymous

Anonymous Mon 16 Aug 2021 11:21:21 No.13525089 Report

Quoted By:

>>13525070
%s/bijective/injective/g
misremembered my definitions

Anonymous

Anonymous Mon 16 Aug 2021 11:24:21 No.13525094 Report

Quoted By: >>13525104 >>13525133

>>13525070
You can guard against misunderstanding by getting rid of this "input/output" language,
which mathematicians do not use, because it does not make formal sense.
But kudos for recognizing that addition and multiplication are functions, and what it
means to be injective/bijective.

Anonymous

Anonymous Mon 16 Aug 2021 11:28:52 No.13525104 Report

Quoted By: >>13525138 >>13525158

>>13525094
>You can guard against misunderstanding by getting rid of this "input/output" language,
which mathematicians do not use
can you elaborate? I'm not a maths major so my knowledge on some stuff is a little barren

Anonymous

Anonymous Mon 16 Aug 2021 11:38:11 No.13525127 Report

Quoted By: >>13525170

OP here
>>13525070
(commutative)Yeah understood that part from other posts. Multiplication matrices are not commutative if I have understood what has been said and with my limited knowledge.
So what does the impossibility that you state relate to?

Also dumb down the jargon i didn't even pass high school, which makes half of the language in your post less than clear. No one can learn about a topic with no knowledge of the sheer basics, this includes jargon.

Anonymous

Anonymous Mon 16 Aug 2021 11:42:20 No.13525133 Report

Quoted By:

>>13525094
What?

Op: is it possible to do x (in simpleton language, due to simpleton education)
Poster: your jargon is wrong dont do it (with no guidance on how to learn as per OPs wishes)

Anonymous

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Anonymous Mon 16 Aug 2021 11:44:55 No.13525137 Report

Quoted By: >>13526886 >>13526911

>>13521591

Anonymous

Anonymous Mon 16 Aug 2021 11:45:06 No.13525138 Report

Quoted By:

>>13525104
In software development input and output are valid to functions which can also be mathematical

Anonymous

Anonymous Mon 16 Aug 2021 11:53:57 No.13525155 Report

Quoted By: >>13525168

>>13521396
Addition is commutative, which means that the order of the terms does not change the value of the result (i.e. for all x and y, $x+y=y+x$ ).
This means that
>1+2+3+4 = 10
>1+2+4+3 = 10
>1+3+4+2 = 10
>1+3+2+4 = 10
>1+4+2+3 = 10
>1+4+3+2 = 10
>2+1+3+4 = 10
>2+1+4+3 = 10
>2+3+1+4 = 10
>2+3+4+1 = 10
>2+4+1+3 = 10
>2+4+3+1 = 10
>3+1+2+4 = 10
>3+1+4+2 = 10
>3+2+1+4 = 10
>3+2+4+1 = 10
>3+4+1+2 = 10
>3+4+2+1 = 10
>4+1+2+3 = 10
>4+1+3+2 = 10
>4+2+1+3 = 10
>4+2+3+1 = 10
>4+3+1+2 = 10
>4+3+2+1 = 10
Not to mention all of the possible permutations with other numbers!
All this to illustrate that the information of order has been lost in the process of addition.

Anonymous

Anonymous Mon 16 Aug 2021 11:54:53 No.13525158 Report

Quoted By: >>13525170

>>13525104
If you see an expression
a = b
stop thinking of a as the input and b as the output. It maybe taught to little kids
that way, but it does not make sense when you begin to treat maths formally. In fact
b = a
is completely logically equivalent. E.g. 2+2=4 is the exact same as 4=2+2.
When you write "input: 1+2+3+4=10", any mathematician will think that you have
specified a string of 10 characters. Whereas you believe that you have described a
function of four variables which sums them up, and when you assign the numbers 1,2,3,4
to those variables, the function value is 10.

Anonymous

Anonymous Mon 16 Aug 2021 11:58:23 No.13525168 Report

Quoted By: >>13526968

OP
>>13525155
Best response yet. The equation in OP was just that an example. In hindsight I could have left it out and just asked is it possible to have an array of size x perform a function to which the answer enables the discovery of the original array and in the same order.

But yes got it now.

Anonymous

Anonymous Mon 16 Aug 2021 12:00:36 No.13525170 Report

Quoted By: >>13525180 >>13525189

>>13525127
let's just go by examples, what numbers did I add together to make 32? You can't know, same for multiplication. Even if you could know the exact numbers that I added together to make 32, you still need to know the order. If you used subtraction and division you could distinguish the order (2-1 is not 1-2), but you still need to know the exact numbers used (3-1 == 4-2). Matrix multiplication lets you work back to find out the order and numbers used because they matter. For matrix multiplication you can multiply the output by the inverse of the "operation" matrix to get the input (as long as the operation is invertible). I know there's some jargon there at the end, but that's the process. Interestingly, this is how quantum computing achieves their invertible operations, as they're all defined by some invertible operation matrix.
>>13525158
I dont think of a=b as input output, but I think of f(x) as having the input x, output f(x). What would be the correct terminology here to refer to the variables we're passing and the result of the operation on those variables?

Anonymous

Anonymous Mon 16 Aug 2021 12:05:38 No.13525180 Report

Quoted By:

Op here
>>13525170
Thanks for the elaboration. I've spent a large portion of the day learning about matrices. DESU got a long way to go to fully understand it. Hear 5 mins then spend countless hours trying to figure out what a word means in the context spoken.

Anonymous

Anonymous Mon 16 Aug 2021 12:12:06 No.13525189 Report

Quoted By:

>>13525170
>I dont think of a=b as input output, but I think of f(x) as having the input x, output f(x). What would be the correct terminology here to refer to the variables we're passing and the result of the operation on those variables?
That is fine and can be understood, even if not formally standard.
You cannot write "input: 1+2+3+4=10" and hope to get understanding from other
than a few cs nerds who never had a formal education.

Anonymous

Anonymous Mon 16 Aug 2021 12:13:42 No.13525192 Report

Quoted By: >>13526746

>>13524358
Why the input limit of 10?

Anonymous

Anonymous Mon 16 Aug 2021 12:52:57 No.13525268 Report

Quoted By: >>13526839

>>13521396
try using some stable sort to get the result of the array sum, something like count sort to preserve the order.

Anonymous

Anonymous Mon 16 Aug 2021 13:57:26 No.13525396 Report

Quoted By: >>13526911

>>13521396
Lmao you're so retarded

Anonymous

Anonymous Mon 16 Aug 2021 22:05:45 No.13526746 Report

Quoted By: >>13526826

>>13525192
As in numerical input would be all integers 0 to 9. Only 10 possibilities for each position vs infinitely many if inputs were reals.

Anonymous

Anonymous Mon 16 Aug 2021 22:40:56 No.13526826 Report

Quoted By: >>13527602

Op here
>>13526746
So if I understand correctly the limit of 10 just reduces the complexity of solving? If not elaborate

Anonymous

Anonymous Mon 16 Aug 2021 22:43:39 No.13526839 Report

Quoted By: >>13526886

>>13525268
The what now?

Anonymous

Anonymous Mon 16 Aug 2021 22:58:43 No.13526875 Report

Quoted By: >>13526911

dude are you mentally retarded?
just look into elementary arithmetic, it explains the axioms and properties that are followed and understood.

Anonymous

Anonymous Mon 16 Aug 2021 23:02:31 No.13526886 Report

Quoted By:

>>13525137
>>13526839

> Whilst you may see what OP has done as laughable, it requires an education way above what OP has said he has, being high school.

> With that said, the lack of intelligence here is not OP, but those who are unable to read something to deduce what is required. Why? Because a year 6 student could.

Anonymous

Anonymous Mon 16 Aug 2021 23:08:31 No.13526911 Report

Quoted By: >>13526943 >>13526949

>>13525396
>>13525137
>>13526875

> Whilst you may see what OP has done as laughable, it requires an education way above what OP has said they have, being high school.

> With that said, the lack of intelligence here is not OP, but those who are unable to read something to deduce what is required. Why? Because a year 6 student could.

Anonymous

Anonymous Mon 16 Aug 2021 23:17:46 No.13526943 Report

Quoted By:

>>13526911
stop jerking off to your farts.
it's not smart that op asked if A,B,C,D could be solved as (1, 2, 3, 4) from A+B+C+D = 10.
g(A, B, C, D) is a function of a 4-tuple/vector input of R^4 where g is the inner product of the input vector and the identity vector.
considering g = 10, wold the solution solve as (1, 2, 3, 4)?
no, it's only an element of the solution space.
Not to mention that in terms of order it's one of 4! permutations included in the solution space.
OP is a fucking dumbass.

Anonymous

Anonymous Mon 16 Aug 2021 23:21:29 No.13526949 Report

Quoted By: >>13528381

>>13526911
There is no excuse for someone who says

6*3*2=2*3*6 =3*3*4=36

Doesn't make sense. Sorry, you're retarded.

Anonymous

Anonymous Mon 16 Aug 2021 23:28:28 No.13526968 Report

Quoted By:

>>13525168
consider the vector x = <x1, x2, x3, x4>
suppose x*<1, 1, 1, 1> = 10
suppose now that xi is a natural number
then suppose that xi < x(i+1)
the only solution space possible is <1, 2, 3, 4>
because you've indicated it must be ordered and restricted to integers above 0.
You need these parameters/restrictions/conditions, or whatever you want to called them, in order to have that precise solution space, otherwise in general, A + B + C + D = 10 can have a very large solution space which will not discriminate to the desired outcome.

Anonymous

Anonymous Mon 16 Aug 2021 23:32:20 No.13526978 Report

Quoted By: >>13526989 >>13527004 >>13527009

Sure, just use a trailing zero as a delimiter:
1 + 2 + 3 + 4 = 10203040
10 + 2 + 3 + 4 = 100203040
If you want something more compact look into information theory, and then you can simply determine the number of bits you need to describe position of each element and construct something from that.

Anonymous

Anonymous Mon 16 Aug 2021 23:35:05 No.13526989 Report

Quoted By: >>13526991 >>13527009

>>13526978
why use the trailing zeros?
what's wrong with
1 + 2 + 3 + 4 = 1234?

Anonymous

Anonymous Mon 16 Aug 2021 23:36:33 No.13526991 Report

Quoted By: >>13526999 >>13527004

>>13526989
That only works for single digits.

Anonymous

Anonymous Mon 16 Aug 2021 23:41:18 No.13526999 Report

Quoted By:

>>13526991
wait:
9 + 10 + 50 + 112 = 91050112
vs 901005001120
I see the zero indicates an exit as to delineate the difference between different additions such as 9 + 99 vs 99 + 9.

Anonymous

Anonymous Mon 16 Aug 2021 23:42:49 No.13527004 Report

Quoted By:

>>13526991
>>13526978
I don't know why but this reminds me about huffman trees.
This stuff is cool, where to I learn more?

Anonymous

Anonymous Mon 16 Aug 2021 23:44:52 No.13527009 Report

Quoted By: >>13527015 >>13527020

>>13526978
>>13526989

This is just storing the same array in a different format, this does not work.

Anonymous

Anonymous Mon 16 Aug 2021 23:47:00 No.13527015 Report

Quoted By: >>13527018

>>13527009
>This is just storing the same array in a different format
Yes. Think about what your asking for a minute. If you want to store position, you need to... store position. If you're looking for obfuscation look into cryptography.

Anonymous

Anonymous Mon 16 Aug 2021 23:50:07 No.13527018 Report

Quoted By: >>13527045

>>13527015
Its been clarified in many posts throughout.
Not looking for anything except to learn.
is it possible to deduce the original array
in the correct order from a mathematical standpoint after no longer having the original array

Anonymous

Anonymous Mon 16 Aug 2021 23:50:46 No.13527020 Report

Quoted By:

>>13527009
<1, 2, 3, 4>*<10^7, 10^5, 1000, 10> = 10203040
we can then easily get the solution of <1, 2, 3, 4>.
seems pretty cool to me.

Anonymous

Anonymous Tue 17 Aug 2021 00:00:12 No.13527045 Report

Quoted By: >>13528361

>>13527018
Information theory for how many bits of information you need to store something distinctly. Abstract algebra for understanding operations(addition, multiplication, etc) on sets and their properties.

Anonymous

Anonymous Tue 17 Aug 2021 04:10:14 No.13527602 Report

Quoted By:

>>13526826
It'd mean you start with more information. It'd be more complex (more steps) to include extra info in calculations but you'd get a solution faster.

Anonymous

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Anonymous Tue 17 Aug 2021 08:35:23 No.13528098 Report

Quoted By:

>>13521396
Your question is hard to decipher, even after reading the thread, but the following are related to what you seem to be trying to achieve:

https://en.wikipedia.org/wiki/G%C3%B6del_numbering

https://en.wikipedia.org/wiki/Asymmetric_numeral_systems

Anonymous

Anonymous Tue 17 Aug 2021 11:21:51 No.13528361 Report

Quoted By:

>>13527045
Thanks for the info.

Bits of info? Is there anything more efficient than using base(2)? from a computer standpoint.

Anonymous

Anonymous Tue 17 Aug 2021 11:32:01 No.13528381 Report

Quoted By: >>13528386

>>13526949
This lmao. O.o I asking for the ability to to differentiate between a, b, and c when a=b=c. Its nonsense, it's like asking to differentiate between a person and that same person; you can't unless you consider some other dimension like time or in his case order. Dumb fucking faggot, delete this shitty thread.

Anonymous

Anonymous Tue 17 Aug 2021 11:33:38 No.13528386 Report

Quoted By:

>>13528381
*OP asked for
Sorry, phone-posting.

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